feat: unify installation model catalog

AGENTS.md

@@ -83,7 +83,8 @@ frontend (React/SSE) → backend (Fastify) → pi --mode rpc → tht/harness →
   `SseHub` fans them out over SSE to the browser. The separate PostgreSQL catalog stores database
   metadata and sequential AI description-generation runs. Description generation samples the DWH
   through read-only connectors and calls a short-lived Python LiteLLM helper; it does not use Pi or
-  expose a public CLI command. App settings still live in `backend/data/settings.json`.
+  expose a public CLI command. Sessions, metadata generation, and embedding resolve models from the
+  generated Installation Model Catalog; `thothii-installation.yaml` is its only authored source.
 
 - **Human-in-the-loop gate contract.** The model proposes; a human reviewer decides at gates
   via widgets (`reviewer_select` = single pick — a chosen option carrying a `decision` payload
@@ -99,11 +100,11 @@ frontend (React/SSE) → backend (Fastify) → pi --mode rpc → tht/harness →
 - **`--json` output must be pristine** (only valid JSON on stdout) — used as a machine contract.
 - **UI strings are English; document *content* stays the workspace language** (Italian for
   `psd`) because it's the real data. Only chrome/labels are English.
-- **Workspaces** (`harness/workspaces/*.yaml`) set the DB target and **absolute**
-  `paths.sessions/artifacts/indexes` — for `psd` these point at a *separate, uncommitted* repo
-  (`tht-workspace-psd/`). Secrets live ONLY in `harness/.env` (gitignored).
-- **Settings are global** (`backend/data/settings.json`: workspace/provider/model/thinking);
-  the New-session form is question-only.
+- **Workspace schema v4** defines database and Evidence concerns only. Embedding/model facts come
+  from the installation catalog. The legacy `harness/workspaces/*.yaml` runtime snapshots still use
+  absolute session/artifact/index paths; secrets stay in `harness/.env` (gitignored).
+- **Settings are global** (`backend/data/settings.json`: workspace/thinking). Provider/model choices
+  are ephemeral canonical catalog selections pinned into the session manifest.
 - **Resume**: a resumable session re-enters at its last incomplete phase. The backend refuses
   resume with 409 when `finalized` or `archived`, and `PiProcessManager.spawnFor` must send
   `/riprendi-sessione <id>` (resume mode) vs `/nuova-domanda` (new) — sending the wrong prompt

PROJECT_STATE.md

@@ -1,6 +1,6 @@
 # ThothII — Project State
 
-Last updated: 2026-08-31.
+Last updated: 2026-09-02.
 
 This file is the short operational snapshot. Stable commands and the architecture mental model
 live in `AGENTS.md`; current design and runtime contracts live under `docs/architecture/`,
@@ -59,10 +59,28 @@ tht --installation /absolute/path/thothii-installation.yaml workspace preprocess
 These commands use the profile-gated `workspace-maintenance` service. The former standalone
 preprocessing Compose fixtures are retired.
 
-Workspace descriptors use schema v3. For PSD, workspace content and runtime roots point to the
+Workspace descriptors use schema v4 and contain only database, Evidence, diagnostics, and binding
+concerns; model, provider, embedding, and vector-store configuration is installation-owned. For
+PSD, workspace content and runtime roots point to the
 separate uncommitted repository `/Users/mp/projects/tht-workspace-psd`. Secrets remain outside
 Git and are supplied only through installation-local protected files.
 
+## Installation Model Catalog
+
+`thothii-installation.yaml` schema version 2 is the only operator-authored source for session,
+metadata-generation, and embedding models. The host `tht` lifecycle validates `modelCatalog` and
+regenerates the backend catalog, Pi `models.json`/`settings.json`, and Compose override under the
+installation-local `generated/` directory. Those projections are replaceable runtime adapters:
+they are not edited, backed up, or treated as configuration.
+
+Session and metadata defaults use canonical `provider/model` IDs. Provider authentication declares
+one explicit mode (`secret_env`, `pi_auth`, or `none`); `secret_env` names a protected bundle key.
+The backend settings store now owns only the selected workspace and thinking level. Existing v1
+installations use the explicit catalog migration command; schema-v3 workspace descriptors are
+converted deterministically in their curator-owned repository before commit. Strict runtime loading
+does not silently infer or merge legacy sources. ADR 0013 and
+`docs/plans/2026-09-02-installation-model-catalog.md` record the decision and implementation.
+
 ## Database management
 
 The database, table, and authoritative physical-schema catalog slices are implemented. Database
@@ -164,7 +182,8 @@ available only when no local start, worker, or helper is live. Runs remain inspe
 live SSE log with ordered polling fallback; there is no automatic resume or user-facing generation
 CLI. ADRs 0009–0010 record the runtime and source-sampling decisions.
 
-Metadata-generation setup accepts the protected `DEEPSEEK_API_KEY` and `ZAI_API_KEY` references.
+The Installation Model Catalog accepts the protected `DEEPSEEK_API_KEY` and `ZAI_API_KEY`
+references for metadata-generation providers.
 It also accepts a model with no secret reference only when its OpenAI-compatible endpoint is
 explicit; this covers the VPN-only AritmoLab Qwen 3.6 server without creating a fake operator
 credential. The Python client supplies only its fixed non-secret compatibility placeholder.

README.md

@@ -106,15 +106,18 @@ a remote user's partial list. The isolated deployment exercise is
 `./scripts/verify-workspace-install-docs.sh --profile local` or `--profile server`.
 
 <!-- workspace-descriptor-contract:start -->
-Schema v3 is the only accepted workspace descriptor. Schema v1 and v2 workspace descriptors are
-rejected before activation. Candidate snapshot validation therefore makes activation or a pull fail
-atomically while the prior valid snapshot remains active. There is no in-product migrator or
-automatic conversion. A repository must already contain reviewed v3 descriptors. One workspace
-owns one Qdrant collection;
+Schema v4 is the only accepted workspace descriptor. Schema v1, v2, and v3 workspace descriptors
+are rejected before activation. Candidate snapshot validation therefore makes activation or a pull
+fail atomically while the prior valid snapshot remains active. One workspace owns one Qdrant collection;
 schema, Evidence, and Memory records share that collection and stay separated by indexed payload
 `kind`.
 <!-- workspace-descriptor-contract:end -->
 
+<!-- non-workspace-migration:start -->
+Convert a v3 descriptor before publication by setting `workspace.schema_version` to `4` and
+removing `llm_policy` and `semantic_index`; no database or Evidence field changes.
+<!-- non-workspace-migration:end -->
+
 For NL→SQL runtime sessions, connector `ssh_tunnel` bindings remain diagnostic-only: their bounded
 probe cleans up the loopback forward and returns `workspace_not_activatable`; session creation is
 rejected before persistence. Database management is a separate boundary and supports a strict
@@ -176,10 +179,10 @@ secret files, upstream-auth checks, and a fail-closed `503` assertion for its de
 unavailable disposable session endpoint. No real provider, database credential, or repository
 secret is required.
 
-For a clean server bind, `scripts/prepare-server-pi-state.sh` creates the hidden regular
-`agent/auth.json`, `agent/models.json`, and `agent/settings.json` mount targets atomically before
-Compose. The server smoke starts from an empty Pi-state root and applies this same preflight; the
-real protected/tracked sources remain separate read-only mounts. Deterministic fixture tests render
+For a clean server bind, `scripts/prepare-server-pi-state.sh` creates the hidden regular Pi agent
+mount targets atomically before Compose. The auth target receives the protected credential bind;
+the model and settings targets receive generated read-only projections. The server smoke starts
+from an empty Pi-state root and applies this same preflight. Deterministic fixture tests render
 both profiles, verify that bindings stay on `core`, check mount readability, and run the production
 workspace resolver. Wrong-service, wrong-value, and broken-secret-mount mutations must fail.
 
@@ -189,7 +192,7 @@ an independent 32-minute outer timeout and does not retry a failed command.
 Current release status (2026-08-05): clean-root render/setup and the production runtime-binding
 resolver contracts are green. The server fixture supplies all four private trusted claims,
 including exact non-admin value `0`, and a focused test proves nginx normalization produces the
-accepted non-admin backend principal. Canonical schema-v3 registry descriptors now pass through
+accepted non-admin backend principal. Canonical schema-v4 registry descriptors now pass through
 one backend-owned, secret-safe runtime handoff for inventory and session execution; canonical
 identity and durable session/artifact/index roots are retained. The fresh update-only smoke passed
 bad-candidate mutation, automatic `rolled_back` compensation, exact prior-image restoration,
@@ -295,14 +298,12 @@ Copy `deploy/secrets/thothii.secrets.example` to a protected host file, include
 keys, and set its absolute path as `THT_SECRETS_FILE` in the operator env. Keep Pi's native
 provider auth in the separate protected file named by `PI_AUTH_FILE`.
 
-Description Generation is configured independently in the protected installation descriptor under
-`metadataGeneration`. Set `THT_INSTALLATION_CONFIG_SOURCE` to that exact host file; Compose mounts
-it read-only into `core` and supplies the fixed runtime `THT_INSTALLATION_CONFIG_FILE` path. Each
-keyed model stores only an audited `apiKeyEnv` reference. The referenced value stays in the secret
-bundle; a model may omit `apiKeyEnv` only when it declares an explicit endpoint that accepts
-unauthenticated requests. The browser receives only model IDs, labels, and the configured default.
-Configuration changes take effect after restart and do not use Pi settings or workspace
-`llm_policy`.
+Interactive sessions, Description Generation, and embedding share the protected installation
+descriptor's `modelCatalog`. Set `THT_INSTALLATION_CONFIG_SOURCE` to that exact host file; `tht`
+validates it and generates the runtime catalog, Pi adapters, and Compose override before startup.
+Each authenticated provider stores only an audited `apiKeyEnv` reference; the referenced value stays
+in the secret bundle. A provider may use `authentication.mode: none` only with an explicit keyless
+endpoint. The browser receives only eligible model IDs, labels, and the catalog default.
 
 Before enabling Description Generation, approve the selected model provider for bounded source-data
 disclosure. Every catalog column has a **Sensitive** flag that defaults to `false`. Administrators can
@@ -333,22 +334,11 @@ the host/secret-manager materialization and add a reviewed Compose override that
 does not create that mount. The frontend remains on loopback; the authenticated host proxy is the
 only public listener.
 
-Set the selected model provider in application settings (or `PI_PROVIDER`). For each Pi spawn the
-backend validates and reads `THT_MODEL_API_KEY` from the bundle, then exposes its value only as the provider's
-recognized child variable (for example `ANTHROPIC_API_KEY`, `OPENAI_API_KEY`, `GEMINI_API_KEY`, or
-`ZAI_API_KEY`). Neither the generic file path nor deprecated `PI_PROVIDER_API_KEY` is inherited by
-Pi. Local providers such as Ollama require no model key.
-
-`THT_MODEL_API_KEY` supports Pi providers whose authentication is exactly one key:
-`ant-ling`, `anthropic`, `cerebras`, `deepseek`, `fireworks`, `github-copilot`, `google`
-(including the `gemini` alias), `google-vertex` when using its API-key mode, `groq`,
-`huggingface`, `kimi-coding`, `minimax`, `minimax-cn`, `mistral`, `moonshotai`,
-`moonshotai-cn`, `nvidia`, `openai`, `opencode`, `opencode-go`, `openrouter`, `together`,
-`vercel-ai-gateway`, `xai`, the four `xiaomi*` providers, `zai`, and `zai-coding-cn`.
-Compound providers are deliberately unsupported: `amazon-bedrock`, `azure-openai-responses`,
-`cloudflare-workers-ai`, and `cloudflare-ai-gateway` require multiple credential/configuration
-values. Selecting one fails before Pi starts; ambient AWS, Azure, and Cloudflare credentials are
-still scrubbed. Supporting them requires a future dedicated provider-specific configuration.
+For each Pi spawn, the backend resolves the selected canonical provider/model in the runtime catalog,
+reads exactly that provider's declared `apiKeyEnv` value from the bundle, and exposes only that key
+to the child. Ambient provider credentials and secret-bundle paths are scrubbed. Providers needing a
+compound credential bundle remain unsupported until the catalog gains an explicit generic contract
+for them.
 
 ## User-owned session server cutover
 

backend/package.json

@@ -9,7 +9,8 @@
     "catalog:migrate": "node dist/catalog/migrate.js",
     "test": "vitest run",
     "start": "node dist/server.js",
-    "test:schema-v3-verifier": "python3 -I -B scripts/test_revision_state_policy.py && node --test scripts/verify-workspace-descriptor-files.test.mjs scripts/revision-state-policy.test.mjs"
+    "test:schema-v4-verifier": "python3 -I -B scripts/test_revision_state_policy.py && node --test scripts/verify-workspace-descriptor-files.test.mjs scripts/revision-state-policy.test.mjs",
+    "test:schema-v3-verifier": "npm run test:schema-v4-verifier"
   },
   "dependencies": {
     "@fastify/cookie": "11.1.2",

backend/scripts/p1-acceptance.mjs

@@ -1195,13 +1195,8 @@ export async function executeChecks({ checks, failAt, recorder } = {}) {
 
 function baseWorkspace(id, evidenceSource) {
   return {
-    workspace: { schema_version: 3, id, name: `P1 ${id}`, language: "en" },
+    workspace: { schema_version: 4, id, name: `P1 ${id}`, language: "en" },
     dwh: { engine: "postgres", database: "postgres", schema: "public", supported_transports: ["postgres_direct"] },
-    semantic_index: {
-      vector_store: { engine: "qdrant", collection: id, dimensions: 1024, distance: "cosine" },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
-    llm_policy: { allowed: ["zai/glm-5.2"] },
     evidence: { source: evidenceSource, policy: { max_chunk_chars: 4000, retain_published_generations: 3 } },
   };
 }

backend/scripts/p1-manual-acceptance.mjs

@@ -109,7 +109,7 @@ async function validateDistFiles(repo,files){const dist=join(repo,"backend","dis
 
 export async function readManualOwnership({repositoryRoot=defaultRepositoryRoot}={}){const repo=realpathSync(repositoryRoot),root=fixedManualRoot(repo);noSymlinkExisting(repo,root);let rootEntry,ownershipEntry;try{rootEntry=await lstat(root);ownershipEntry=await lstat(join(root,"ownership.json"));}catch{throw new Error("manual ownership is missing");}if(!rootEntry.isDirectory()||rootEntry.isSymbolicLink()||await realpath(root)!==root||!ownershipEntry.isFile()||ownershipEntry.isSymbolicLink())throw new Error("manual ownership is unsafe");let value;try{value=JSON.parse(await readFile(join(root,"ownership.json"),"utf8"));}catch{throw new Error("manual ownership is malformed");}const baseValid=value.schemaVersion===1&&value.kind==="p1-manual-acceptance"&&HEX64.test(value.nonce??"")&&value.repositoryRoot===repo&&value.root===root&&value.status==="PENDING"&&["PREPARING","READY"].includes(value.stage)&&value.listener?.host===HOST&&value.listener?.port===PORT&&value.listener?.state==="stopped"&&typeof value.createdAt==="string"&&validEntrypoint(value.entrypoint,repo)&&validDistManifest(value.distManifest,root)&&JSON.stringify(value.resources)===JSON.stringify([root,{kind:"fastify",host:HOST,port:PORT}]);const readyLog=value.backendLog?.path===join(root,"logs/backend.log")&&Number.isSafeInteger(value.backendLog?.dev)&&Number.isSafeInteger(value.backendLog?.ino);if(!baseValid||(value.stage==="READY"?!readyLog:value.backendLog!==null))throw new Error("manual ownership identity mismatch");return value;}
 async function run(executable,argv,options={}){return await exec(executable,argv,{...options,maxBuffer:2*1024*1024,encoding:"utf8"});}
-function descriptor(id,source){return{workspace:{schema_version:3,id,name:`P1 ${id}`,language:"en"},dwh:{engine:"postgres",database:"postgres",schema:"public",supported_transports:["postgres_direct"]},semantic_index:{vector_store:{engine:"qdrant",collection:id,dimensions:1024,distance:"cosine"},embedding:{provider:"ollama_internal",model:"qwen3-embedding:0.6b",dimensions:1024}},llm_policy:{allowed:["zai/glm-5.2"]},evidence:{source,policy:{max_chunk_chars:4000,retain_published_generations:3}}};}
+function descriptor(id,source){return{workspace:{schema_version:4,id,name:`P1 ${id}`,language:"en"},dwh:{engine:"postgres",database:"postgres",schema:"public",supported_transports:["postgres_direct"]},evidence:{source,policy:{max_chunk_chars:4000,retain_published_generations:3}}};}
 function descriptors(){return[descriptor("p1-filesystem",{type:"filesystem",uri:"workspace-content/p1-filesystem/evidence",patterns:["**/*.md"],max_bytes:10485760}),descriptor("p1-http",{type:"http",uris:["https://evidence.example.test/guide.md"],authentication:"signed_urls_file",connect_timeout_ms:1250,read_timeout_ms:30001,max_bytes:12345,max_redirects:2,allow_private_hosts:false,max_cache_bytes:67890}),descriptor("p1-s3",{type:"s3",uri:"s3://p1-evidence/published/",endpoint_url:"https://s3.example.test/",region:"eu-west-1",credentials:"static_files",trusted_endpoint:true,allow_private_endpoint:false,allow_insecure_endpoint:false,max_bytes:12345,max_objects:33,max_pages:4,page_size:5})];}
 function quote(value){return `'${String(value).replaceAll("'",`'"'"'`)}'`;}
 async function checkPrerequisites(repo){for(const path of ["scripts/p1-acceptance.sh","scripts/test-p1-acceptance.sh","backend/scripts/p1-acceptance.mjs","backend/dist/server.js"]){try{await access(join(repo,path));}catch{throw new Error(`Task 8 prerequisite is missing: ${path}`);}}for(const command of ["node","npm","git","curl","unzip","zipinfo","lsof","python3"]){try{await run(command,[command==="unzip"||command==="lsof"?"-v":command==="zipinfo"?"-h":"--version"]);}catch{throw new Error(`missing prerequisite: ${command}`);}}const tht=join(repo,"harness",".venv","bin","tht");try{await access(tht,constants.X_OK);}catch{throw new Error("missing prerequisite: harness/.venv/bin/tht");}}

backend/scripts/p1-manual-acceptance.test.mjs

@@ -403,7 +403,7 @@ test("generated render command validates saved responses and owned snapshot befo
 });
 
 const renderSnapshotYaml=`workspace:
-  schema_version: 3
+  schema_version: 4
   id: p1-filesystem
   name: P1 filesystem
   language: en
@@ -412,11 +412,6 @@ dwh:
   database: postgres
   schema: public
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store: {engine: qdrant, collection: p1-filesystem, dimensions: 1024, distance: cosine}
-  embedding: {provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024}
-llm_policy:
-  allowed: [zai/glm-5.2]
 evidence:
   source: {type: filesystem, uri: workspace-content/p1-filesystem/evidence, patterns: ["**/*.md"], max_bytes: 10485760}
   policy: {max_chunk_chars: 4000, retain_published_generations: 3}

backend/scripts/p1-render-snapshot.test.mjs

@@ -16,7 +16,7 @@ async function fixture() {
  await writeFile(join(root,"installation/base.yaml"),"{}\n");
  const secret=join(root,"fixture-secrets/dwh-password"); await writeFile(secret,"not-inspected",{mode:0o600});
  await writeFile(snapshot,`workspace:
-  schema_version: 3
+  schema_version: 4
   id: p1-filesystem
   name: P1 filesystem
   language: en
@@ -25,11 +25,6 @@ dwh:
   database: postgres
   schema: public
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store: {engine: qdrant, collection: p1-filesystem, dimensions: 1024, distance: cosine}
-  embedding: {provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024}
-llm_policy:
-  allowed: [zai/glm-5.2]
 evidence:
   source: {type: filesystem, uri: workspace-content/p1-filesystem/evidence, patterns: ["**/*.md"], max_bytes: 10485760}
   policy: {max_chunk_chars: 4000, retain_published_generations: 3}
@@ -61,7 +56,7 @@ test("renderer refuses snapshot manifest head, digest, and expected-digest tampe
 
 test("renderer refuses a missing or malformed snapshot manifest",async()=>{ const f=await fixture(); const output=join(f.root,"rendered/nomanifest.yaml"); await rm(f.manifestPath); await assert.rejects(call(f,{outputPath:output}),/snapshot manifest.*(missing|unbounded|unsafe)/); await writeFile(f.manifestPath,"{not json"); await assert.rejects(call(f,{outputPath:output}),/snapshot manifest.*malformed/); await assert.rejects(lstat(output)); assert.deepEqual(await runtimeLeases(f),[]); });
 
-test("renderer rejects a regular snapshot replacement against its manifest",async()=>{ const f=await fixture(); const output=join(f.root,"rendered/replaced.yaml"); await assert.rejects(call(f,{outputPath:output,beforePublish:async()=>{await writeFile(f.snapshot,"workspace:\n  schema_version: 3\n  id: p1-filesystem\n  name: replaced\n")}}),/snapshot content changed/); await assert.rejects(lstat(output)); });
+test("renderer rejects a regular snapshot replacement against its manifest",async()=>{ const f=await fixture(); const output=join(f.root,"rendered/replaced.yaml"); await assert.rejects(call(f,{outputPath:output,beforePublish:async()=>{await writeFile(f.snapshot,"workspace:\n  schema_version: 4\n  id: p1-filesystem\n  name: replaced\n")}}),/snapshot content changed/); await assert.rejects(lstat(output)); });
 
 test("renderer anchors publication when rendered parent is concurrently swapped", async()=>{
  const f=await fixture(),output=join(f.root,"rendered/raced.yaml"),moved=join(f.root,"rendered-moved"),outside=join(f.repo,"outside-rendered"); await mkdir(outside);

backend/scripts/p11-acceptance.mjs

@@ -328,13 +328,8 @@ async function tht(ctx, argv, options = {}) {
 function namespace(id) { return id.toUpperCase().replaceAll("-", "_"); }
 function baseWorkspace(id, evidenceSource) {
   return {
-    workspace: { schema_version: 3, id, name: `P1.1 ${id}`, description: `Catalog entry for ${id}`, language: "en" },
+    workspace: { schema_version: 4, id, name: `P1.1 ${id}`, description: `Catalog entry for ${id}`, language: "en" },
     dwh: { engine: "postgres", database: "postgres", schema: "public", supported_transports: ["postgres_direct"] },
-    semantic_index: {
-      vector_store: { engine: "qdrant", collection: id, dimensions: 1024, distance: "cosine" },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
-    llm_policy: { allowed: ["zai/glm-5.2"] },
     evidence: { source: evidenceSource, policy: { max_chunk_chars: 4000, retain_published_generations: 3 } },
   };
 }

backend/scripts/p11-manual-acceptance.mjs

@@ -81,13 +81,8 @@ async function git(executable, argv, options = {}) {
 function namespace(id) { return id.toUpperCase().replaceAll("-", "_"); }
 function baseWorkspace(id, evidenceSource) {
   return {
-    workspace: { schema_version: 3, id, name: `P1.1 ${id}`, description: `Catalog entry for ${id}`, language: "en" },
+    workspace: { schema_version: 4, id, name: `P1.1 ${id}`, description: `Catalog entry for ${id}`, language: "en" },
     dwh: { engine: "postgres", database: "postgres", schema: "public", supported_transports: ["postgres_direct"] },
-    semantic_index: {
-      vector_store: { engine: "qdrant", collection: id, dimensions: 1024, distance: "cosine" },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
-    llm_policy: { allowed: ["zai/glm-5.2"] },
     evidence: { source: evidenceSource, policy: { max_chunk_chars: 4000, retain_published_generations: 3 } },
   };
 }

backend/scripts/p2-acceptance.mjs

@@ -375,16 +375,11 @@ function installationProjectName(installationPath) {
 
 function baseWorkspace(id, { dwhBaseUrl, evidenceSource }) {
   return {
-    workspace: { schema_version: 3, id, name: `P2 ${id}`, language: "en" },
+    workspace: { schema_version: 4, id, name: `P2 ${id}`, language: "en" },
     dwh: { engine: "postgres", database: "warehouse", schema: "dw", supported_transports: ["rest_api"] },
-    semantic_index: {
-      vector_store: { engine: "qdrant", collection: id, dimensions: 1024, distance: "cosine" },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
     diagnostics: {
       dwh_rest: { method: "POST", path: "/rpc/ping", auth: "x-api-key", response: { database: "database", schema: "schema" } },
     },
-    llm_policy: { allowed: ["zai/glm-5.2"] },
     ...(evidenceSource ? { evidence: { source: evidenceSource, policy: { max_chunk_chars: 4000, retain_published_generations: 3 } } } : {}),
   };
 }

backend/scripts/p2p6-acceptance.mjs

@@ -376,16 +376,11 @@ function installationProjectName(installationPath) {
 
 function baseWorkspace(id, { dwhBaseUrl, evidenceSource }) {
   return {
-    workspace: { schema_version: 3, id, name: `P2 ${id}`, language: "en" },
+    workspace: { schema_version: 4, id, name: `P2 ${id}`, language: "en" },
     dwh: { engine: "postgres", database: "warehouse", schema: "dw", supported_transports: ["rest_api"] },
-    semantic_index: {
-      vector_store: { engine: "qdrant", collection: id, dimensions: 1024, distance: "cosine" },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
     diagnostics: {
       dwh_rest: { method: "POST", path: "/rpc/ping", auth: "x-api-key", response: { database: "database", schema: "schema" } },
     },
-    llm_policy: { allowed: ["zai/glm-5.2"] },
     ...(evidenceSource ? { evidence: { source: evidenceSource, policy: { max_chunk_chars: 4000, retain_published_generations: 3 } } } : {}),
   };
 }

backend/scripts/p3-acceptance.mjs

@@ -379,16 +379,11 @@ function installationProjectName(installationPath) {
 
 function baseWorkspace(id, { dwhBaseUrl, evidenceSource }) {
   return {
-    workspace: { schema_version: 3, id, name: `P2 ${id}`, language: "en" },
+    workspace: { schema_version: 4, id, name: `P2 ${id}`, language: "en" },
     dwh: { engine: "postgres", database: "warehouse", schema: "dw", supported_transports: ["rest_api"] },
-    semantic_index: {
-      vector_store: { engine: "qdrant", collection: id, dimensions: 1024, distance: "cosine" },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
     diagnostics: {
       dwh_rest: { method: "POST", path: "/rpc/ping", auth: "x-api-key", response: { database: "database", schema: "schema" } },
     },
-    llm_policy: { allowed: ["zai/glm-5.2"] },
     ...(evidenceSource ? { evidence: { source: evidenceSource, policy: { max_chunk_chars: 4000, retain_published_generations: 3 } } } : {}),
   };
 }

backend/scripts/p5-acceptance.mjs

@@ -374,16 +374,11 @@ function installationProjectName(installationPath) {
 
 function baseWorkspace(id, { dwhBaseUrl, evidenceSource }) {
   return {
-    workspace: { schema_version: 3, id, name: `P2 ${id}`, language: "en" },
+    workspace: { schema_version: 4, id, name: `P2 ${id}`, language: "en" },
     dwh: { engine: "postgres", database: "warehouse", schema: "dw", supported_transports: ["rest_api"] },
-    semantic_index: {
-      vector_store: { engine: "qdrant", collection: id, dimensions: 1024, distance: "cosine" },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
     diagnostics: {
       dwh_rest: { method: "POST", path: "/rpc/ping", auth: "x-api-key", response: { database: "database", schema: "schema" } },
     },
-    llm_policy: { allowed: ["zai/glm-5.2"] },
     ...(evidenceSource ? { evidence: { source: evidenceSource, policy: { max_chunk_chars: 4000, retain_published_generations: 3 } } } : {}),
   };
 }

backend/scripts/p6-acceptance.mjs

@@ -374,16 +374,11 @@ function installationProjectName(installationPath) {
 
 function baseWorkspace(id, { dwhBaseUrl, evidenceSource }) {
   return {
-    workspace: { schema_version: 3, id, name: `P2 ${id}`, language: "en" },
+    workspace: { schema_version: 4, id, name: `P2 ${id}`, language: "en" },
     dwh: { engine: "postgres", database: "warehouse", schema: "dw", supported_transports: ["rest_api"] },
-    semantic_index: {
-      vector_store: { engine: "qdrant", collection: id, dimensions: 1024, distance: "cosine" },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
     diagnostics: {
       dwh_rest: { method: "POST", path: "/rpc/ping", auth: "x-api-key", response: { database: "database", schema: "schema" } },
     },
-    llm_policy: { allowed: ["zai/glm-5.2"] },
     ...(evidenceSource ? { evidence: { source: evidenceSource, policy: { max_chunk_chars: 4000, retain_published_generations: 3 } } } : {}),
   };
 }

backend/scripts/verify-workspace-descriptor-files.mjs

@@ -36,11 +36,10 @@ const reviewedExpandableBlocks = new Map([
     { sha256: "b903e5dae953ae1372f1a5276f12a92ed3dd632b897f3afe5e00c646d90a1b42", rationale: "Same reviewed block in the repository-required CRLF checkout representation." },
   ]],
   ["scripts/unified-deployment-smoke.sh", [
-    { sha256: "1d60bf140165a8fabfa0c3729e776136904717e67becf3e0ab68c70d8e37847e", rationale: "Generates reviewed Task 13 runtime configuration." },
-    { sha256: "36d3d8a2362dbdc4fad90948d6c227586d749f56b9a4bc5b6b5a91bcbec6407b", rationale: "Generates the reviewed local Task 13 Compose override." },
-    { sha256: "c556f7d910d0788e219b042957e6b307cb9925b43920c680535d0d3a6dcbdb25", rationale: "Generates the reviewed local Task 13 installation descriptor." },
+    { sha256: "b6c0826151b2c8b955399d1abf5b691cc8fe6b6454b17da000dde7ba3bc55d2d", rationale: "Generates the reviewed local Task 13 Compose override with normalized catalog mounts." },
+    { sha256: "24f69d12b8554aa2bebba455be99fde3e60743eef5a40fa2ef5b29397a477c03", rationale: "Generates the reviewed local Task 13 installation descriptor with its model catalog." },
     { sha256: "526006fa6d48a8080b3834723630c64de5005a67243e944ebf1da15212b4d654", rationale: "Generates the reviewed server Task 13 Compose override." },
-    { sha256: "c57ae2205c21ead0c2015a353aaabb948fa4ddd9b78a2cdcdb71f48cf2db742d", rationale: "Generates the reviewed projected-auth server Task 13 installation descriptor." },
+    { sha256: "406ccead1967f642225c946fc4a23fe5b019c9764cc5153e1125876ade16ec90", rationale: "Generates the reviewed projected-auth server Task 13 installation descriptor with its model catalog." },
   ]],
   ["scripts/vector-backup.sh", [
     { sha256: "571899db49dfdcec8107fbe1e0a86a61e7581979d3c4c248c20546843e275bcf", rationale: "Generates the reviewed backup manifest inside the helper command." },
@@ -103,6 +102,7 @@ function isPolicyImplementationException(label, category) {
   ]);
   if (implementations.has(label)) return true;
   if (category === "migration-marker" && new Set([
+    "backend/src/workspaces/schema.ts",
     "scripts/workspace_descriptor_doc_contract.py",
     "scripts/test_workspace_descriptor_doc_contract.py",
     "backend/scripts/clean-dist.test.mjs",
@@ -173,7 +173,7 @@ function validateWorkspaceSource(source, label, { requireWorkspace, expandable =
   try {
     parseWorkspaceYaml(source);
   } catch (error) {
-    throw new Error(`${label}: workspace descriptor is not valid schema v3: ${error instanceof Error ? error.message : String(error)}`);
+    throw new Error(`${label}: workspace descriptor is not valid schema v4: ${error instanceof Error ? error.message : String(error)}`);
   }
   return true;
 }

backend/scripts/verify-workspace-descriptor-files.test.mjs

@@ -33,20 +33,20 @@ function bashN(root, path) {
 function replaceWorkspaceKeys(source, workspaceKey, schemaLine) {
   return source
     .replace(/^workspace:$/m, workspaceKey)
-    .replace(/^  schema_version: 3$/m, schemaLine);
+    .replace(/^  schema_version: 4$/m, schemaLine);
 }
 
-test("production parser accepts semantic v3 with quoted Unicode/tagged keys and spacing", async (t) => {
+test("production parser accepts semantic v4 with quoted Unicode/tagged keys and spacing", async (t) => {
   const root = await fixture(t);
   const unicode = replaceWorkspaceKeys(
     canonicalDescriptor,
     '"\\u0077orkspace" :',
-    '  "\\u0073chema_version" : 3',
+    '  "\\u0073chema_version" : 4',
   );
   const tagged = replaceWorkspaceKeys(
     canonicalDescriptor,
     "!!str workspace :",
-    "  !!str schema_version : 3",
+    "  !!str schema_version : 4",
   );
   await put(root, "deploy/workspaces/unicode.yaml", unicode);
   await put(root, "deploy/workspaces/tagged.yaml", tagged);
@@ -59,14 +59,15 @@ test("production parser accepts semantic v3 with quoted Unicode/tagged keys and
   });
 });
 
-test("production parser rejects fancy keys with every non-v3 or ambiguous value", async (t) => {
+test("production parser rejects fancy keys with every non-v4 or ambiguous value", async (t) => {
   const invalid = [
     ["unicode-v2", '"\\u0077orkspace" :', '  "\\u0073chema_version" : 2'],
-    ["tagged-leading-zero", "!!str workspace :", "  !!str schema_version : 02"],
-    ["hexadecimal", "workspace :", "  schema_version : 0x2"],
-    ["multiline", "workspace :", "  schema_version : >\n    3"],
-    ["duplicate", "workspace :", "  schema_version : 3\n  schema_version: 3"],
-    ["inline", "workspace: { schema_version: 3 }", "  schema_version: 3"],
+    ["unicode-v3", '"\\u0077orkspace" :', '  "\\u0073chema_version" : 3'],
+    ["tagged-leading-zero", "!!str workspace :", "  !!str schema_version : 03"],
+    ["hexadecimal", "workspace :", "  schema_version : 0x3"],
+    ["multiline", "workspace :", "  schema_version : >\n    4"],
+    ["duplicate", "workspace :", "  schema_version : 4\n  schema_version: 4"],
+    ["inline", "workspace: { schema_version: 4 }", "  schema_version: 4"],
   ];
   for (const [name, workspaceKey, schemaLine] of invalid) {
     await t.test(name, async () => {
@@ -120,7 +121,7 @@ test("PowerShell embedded workspace mappings are rejected while bundle-only stri
   const root = await fixture(t);
   const source = [
     "$workspace = @'",
-    canonicalDescriptor.replace("  schema_version: 3", "  schema_version: 0x2").trimEnd(),
+    canonicalDescriptor.replace("  schema_version: 4", "  schema_version: 0x2").trimEnd(),
     "'@",
     '$bundle = @"',
     "bundle:",
@@ -137,7 +138,7 @@ test("PowerShell embedded workspace mappings are rejected while bundle-only stri
 
 test("workspace descriptor family entries require a top-level workspace", async (t) => {
   const root = await fixture(t);
-  await put(root, "scripts/fixtures/workspace-registry-future.yaml", "bundle:\n  schema_version: 3\n");
+  await put(root, "scripts/fixtures/workspace-registry-future.yaml", "bundle:\n  schema_version: 4\n");
   await assert.rejects(
     verifyEntries({
       root,
@@ -179,7 +180,7 @@ test("script scalar workspace remains a bundle even with descriptor-like sibling
 test("standalone descriptor files require workspace to be a mapping", async (t) => {
   const root = await fixture(t);
   const path = "scripts/fixtures/workspace-registry-scalar.yaml";
-  await put(root, path, "workspace: analytics\nschema_version: 3\n");
+  await put(root, path, "workspace: analytics\nschema_version: 4\n");
   await assert.rejects(
     verifyEntries({ root, entries: [entry("workspace_descriptor", path)] }),
     /workspace.*mapping/i,
@@ -193,11 +194,11 @@ test("Bash extractor supports hyphen, digit, escaped delimiters, and tab strippi
       name: "hyphen-v2",
       opener: "cat <<'WORKSPACE-YAML'",
       delimiter: "WORKSPACE-YAML",
-      descriptor: canonicalDescriptor.replace("  schema_version: 3", "  schema_version: 2"),
+      descriptor: canonicalDescriptor.replace("  schema_version: 4", "  schema_version: 2"),
       rejected: true,
     },
     {
-      name: "digit-v3",
+      name: "digit-v4",
       opener: "cat <<2YAML",
       delimiter: "2YAML",
       descriptor: canonicalDescriptor,
@@ -207,11 +208,11 @@ test("Bash extractor supports hyphen, digit, escaped delimiters, and tab strippi
       name: "escaped-v2",
       opener: "cat <<WORKSPACE\\-YAML",
       delimiter: "WORKSPACE-YAML",
-      descriptor: canonicalDescriptor.replace("  schema_version: 3", "  schema_version: 2"),
+      descriptor: canonicalDescriptor.replace("  schema_version: 4", "  schema_version: 2"),
       rejected: true,
     },
     {
-      name: "tab-strip-v3",
+      name: "tab-strip-v4",
       opener: "cat <<-'TAB-YAML'",
       delimiter: "\tTAB-YAML",
       descriptor: canonicalDescriptor.split("\n").map((line) => `\t${line}`).join("\n"),
@@ -272,7 +273,7 @@ test("non-stripping heredoc close requires an exact physical delimiter line", as
     "#!/usr/bin/env bash",
     "cat <<'---'",
     "---   ",
-    canonicalDescriptor.replace("  schema_version: 3", "  schema_version: 2").trimEnd(),
+    canonicalDescriptor.replace("  schema_version: 4", "  schema_version: 2").trimEnd(),
     "---",
     "",
   ].join("\n");
@@ -313,7 +314,7 @@ test("double-quoted non-special backslash is preserved in the delimiter", async
     "#!/usr/bin/env bash",
     'cat <<"\\---"',
     "---",
-    canonicalDescriptor.replace("  schema_version: 3", "  schema_version: 2").trimEnd(),
+    canonicalDescriptor.replace("  schema_version: 4", "  schema_version: 2").trimEnd(),
     "\\---",
     "",
   ].join("\n");
@@ -355,7 +356,7 @@ test("split heredoc operator continuation cannot bypass v2 validation", async (t
     "#!/usr/bin/env bash",
     "cat <\\",
     "<'YAML'",
-    canonicalDescriptor.replace("  schema_version: 3", "  schema_version: 2").trimEnd(),
+    canonicalDescriptor.replace("  schema_version: 4", "  schema_version: 2").trimEnd(),
     "YAML",
     "",
   ].join("\n");
@@ -424,7 +425,7 @@ test("PowerShell comment backslash cannot hide a following v2 here-string", asyn
   const source = [
     "# harmless PowerShell comment \\",
     "$workspace = @'",
-    canonicalDescriptor.replace("  schema_version: 3", "  schema_version: 2").trimEnd(),
+    canonicalDescriptor.replace("  schema_version: 4", "  schema_version: 2").trimEnd(),
     "'@",
     "",
   ].join("\n");
@@ -435,7 +436,7 @@ test("PowerShell comment backslash cannot hide a following v2 here-string", asyn
   );
 });
 
-test("PowerShell dialect accepts normal v3 and non-workspace bundle here-strings", async (t) => {
+test("PowerShell dialect accepts normal v4 and non-workspace bundle here-strings", async (t) => {
   const root = await fixture(t);
   const path = "scripts/powershell-valid-smoke.ps1";
   const source = [
@@ -494,10 +495,10 @@ test("PowerShell cast and concatenation openers cannot hide embedded descriptors
 test("expandable YAML interpolation that can hide a workspace descriptor fails closed", async (t) => {
   const root = await fixture(t);
   const cases = [
-    ["braced-key", "${key}:\n  schema_version: 3"],
-    ["plain-key", "$key:\n  schema_version: 3"],
-    ["quoted-key", '"$key" :\n  schema_version: 3'],
-    ["subexpression-key", "$($key):\n  schema_version: 3"],
+    ["braced-key", "${key}:\n  schema_version: 4"],
+    ["plain-key", "$key:\n  schema_version: 4"],
+    ["quoted-key", '"$key" :\n  schema_version: 4'],
+    ["subexpression-key", "$($key):\n  schema_version: 4"],
     ["version", "workspace:\n  schema_version: $version"],
   ];
   for (const [name, body] of cases) {
@@ -564,7 +565,7 @@ test("unmarked expandable Bash YAML cannot generate descriptor keys or values at
       "key=workspace",
       "cat <<YAML",
       generatedKey,
-      "  schema_version: 3",
+      "  schema_version: 4",
       "YAML",
       "",
     ].join("\n");
@@ -600,14 +601,14 @@ test("an in-band marker cannot authorize expandable content", async (t) => {
   for (const [path, source] of [
     ["scripts/fake-marker.sh", [
       "#!/usr/bin/env bash",
-      "# schema-v3-only: expandable-nonworkspace",
+      "# schema-v4-only: expandable-nonworkspace",
       "cat <<YAML",
       "${DESCRIPTOR}",
       "YAML",
       "",
     ].join("\n")],
     ["scripts/fake-marker.ps1", [
-      "# schema-v3-only: expandable-nonworkspace",
+      "# schema-v4-only: expandable-nonworkspace",
       '$yaml = @"',
       "$descriptor",
       '"@',

backend/src/app.ts

@@ -22,7 +22,8 @@ import { isUsableAuthenticationSecret } from "./auth/secret-policy.js";
 import { secretValue } from "./config/secret-bundle.js";
 import { sessionRoutes } from "./routes/sessions.js";
 import { sqlRoutes } from "./routes/sql.js";
-import { metaRoutes, type ListModelsFn } from "./routes/meta.js";
+import { metaRoutes } from "./routes/meta.js";
+import type { ListModelsFn } from "./pi/list-models.js";
 import { settingsRoutes, effectiveSettings } from "./routes/settings.js";
 import { createPiModelLister } from "./pi/list-models.js";
 import { createPiManagement, type PiManagementService } from "./pi/management.js";
@@ -66,6 +67,7 @@ import { catalogDescriptionGenerationRoutes } from "./routes/catalog-description
 import { CatalogLogicalRelationshipService } from "./catalog/logical-relationship-service.js";
 import { catalogLogicalRelationshipRoutes } from "./routes/catalog-logical-relationships.js";
 import { EffectiveRelationshipSnapshotProvider } from "./catalog/effective-relationship-snapshot.js";
+import { loadRuntimeModelCatalog, type RuntimeModelCatalog } from "./models/runtime-model-catalog.js";
 
 export interface BuildAppDeps {
   thtRunner?: ThtRunner;
@@ -88,6 +90,7 @@ export interface BuildAppDeps {
   catalogSyncWorker?: CatalogSyncWorker;
   catalogOperationCoordinator?: CatalogOperationCoordinator;
   metadataGenerationModels?: MetadataGenerationModels;
+  runtimeModelCatalog?: RuntimeModelCatalog;
   modelCompleter?: ModelCompleter;
   descriptionSourceSampler?: DescriptionSourceSampler;
   workspaceRuntimeSupport?: (workspace: WorkspaceDescriptor) => boolean;
@@ -155,17 +158,22 @@ export function buildApp(config: AppConfig, deps?: BuildAppDeps): FastifyInstanc
     semanticRuntime: {
       internalQdrantUrl: config.internalQdrantUrl,
       internalEmbeddingUrl: config.internalEmbeddingUrl,
+      internalEmbeddingId: config.internalEmbeddingId,
       internalEmbeddingModel: config.internalEmbeddingModel,
       internalEmbeddingDimensions: config.internalEmbeddingDimensions,
     },
   });
-  const mgr = deps?.mgr ?? new PiProcessManager(config, deps?.spawnFn ? { spawnFn: deps.spawnFn } : undefined);
   const hub = deps?.hub ?? new SseHub();
   const workspaceRegistry = deps?.workspaceRegistry ?? new WorkspaceRegistry(config.workspaceRegistry);
   const catalogRepository = deps?.catalogRepository ?? createCatalogRepository(config.catalogDatabase);
   const catalogOperationCoordinator = deps?.catalogOperationCoordinator ?? new CatalogOperationCoordinator();
+  const runtimeModelCatalog = deps?.runtimeModelCatalog ?? loadRuntimeModelCatalog(config.modelCatalogFile);
+  const mgr = deps?.mgr ?? new PiProcessManager(config, {
+    ...(deps?.spawnFn ? { spawnFn: deps.spawnFn } : {}),
+    modelCatalog: runtimeModelCatalog,
+  });
   const metadataGenerationModels = deps?.metadataGenerationModels ?? loadMetadataGenerationModels({
-    installationFile: config.installationConfigFile,
+    catalogFile: config.modelCatalogFile,
     secretsFile: config.secretsFile,
   });
   const modelCompleter = deps?.modelCompleter ?? new PythonModelCompleter({
@@ -237,6 +245,7 @@ export function buildApp(config: AppConfig, deps?: BuildAppDeps): FastifyInstanc
     ?? createProductionWorkspaceDiagnoser(config.workspaceDiagnosticTimeoutMs, undefined, {
       internalQdrantUrl: config.internalQdrantUrl,
       internalEmbeddingUrl: config.internalEmbeddingUrl,
+      internalEmbeddingId: config.internalEmbeddingId,
       internalEmbeddingModel: config.internalEmbeddingModel,
       internalEmbeddingDimensions: config.internalEmbeddingDimensions,
     });
@@ -271,7 +280,7 @@ export function buildApp(config: AppConfig, deps?: BuildAppDeps): FastifyInstanc
   const getSettings = async (principal: PrincipalContext): Promise<Settings> => {
     if (deps?.getSettings) return await deps.getSettings(principal);
     const stored = loadSettings(config);
-    const effective = effectiveSettings(config, stored);
+    const effective = effectiveSettings(config, stored, runtimeModelCatalog);
     // In the registry system the legacy `harness/workspaces/*.yaml` default is obsolete: when no
     // installation workspace is pinned, default to the first active registry workspace.
     if (!stored.workspace) {
@@ -284,7 +293,9 @@ export function buildApp(config: AppConfig, deps?: BuildAppDeps): FastifyInstanc
     }
     return effective;
   };
-  const piManagement = deps?.piManagement ?? createPiManagement(config, { listModels });
+  const piManagement = deps?.piManagement ?? createPiManagement(config, {
+    modelCatalog: runtimeModelCatalog,
+  });
 
   const maintenanceBarrier = deps?.maintenanceBarrier ?? new MaintenanceBarrier(config.maintenanceFile);
   const localRegistryResolver = deps?.localUserRegistry === undefined
@@ -408,6 +419,7 @@ export function buildApp(config: AppConfig, deps?: BuildAppDeps): FastifyInstanc
     dwhPrecheck: config.dwhPrecheck,
     legacyWorkspaceMode: config.legacyWorkspaceMode,
     workspaceRuntimeSupport,
+    modelCatalog: runtimeModelCatalog,
     maintenanceBarrier,
     effectiveRelationships,
   });
@@ -439,7 +451,7 @@ export function buildApp(config: AppConfig, deps?: BuildAppDeps): FastifyInstanc
     return maintenanceBarrier.status();
   });
   sqlRoutes(app, { tht: tht as ThtRunner, getSettings, workspaceRegistry });
-  metaRoutes(app, { harnessDir: config.harnessDir, listModels });
+  metaRoutes(app, { harnessDir: config.harnessDir, modelCatalog: runtimeModelCatalog });
   workspaceRoutes(app, {
     registry: workspaceRegistry,
     config: config.workspaceRegistry,
@@ -472,7 +484,7 @@ export function buildApp(config: AppConfig, deps?: BuildAppDeps): FastifyInstanc
     worker: descriptionGenerationWorker,
     sensitiveDataSuggestionRunner,
   });
-  settingsRoutes(app, { cfg: config, listModels, getSettings });
+  settingsRoutes(app, { cfg: config, getSettings });
   piManagementRoutes(app, { service: piManagement });
 
   return app;

backend/src/catalog/metadata-generation-models.ts

@@ -1,63 +1,5 @@
-import {
-  closeSync, constants, fstatSync, lstatSync, openSync, readFileSync,
-  type Stats,
-} from "node:fs";
-import { parseAllDocuments } from "yaml";
-import { z } from "zod";
-import {
-  loadSecretBundle,
-  METADATA_GENERATION_SECRET_KEYS,
-} from "../config/secret-bundle.js";
-
-const MAX_INSTALLATION_BYTES = 1024 * 1024;
-const RUNTIME_INSTALLATION_FILE = "/run/thothii-installation/thothii-installation.yaml";
-const modelId = z.string().regex(/^[a-z][a-z0-9._-]{0,63}$/);
-const apiKeyEnvironment = z.enum(METADATA_GENERATION_SECRET_KEYS);
-const endpointSchema = z.object({
-  baseUrl: z.string().min(1).max(2048).refine((value) => {
-    try {
-      const url = new URL(value);
-      return (url.protocol === "http:" || url.protocol === "https:")
-        && url.username === "" && url.password === "" && url.search === "" && url.hash === "";
-    } catch {
-      return false;
-    }
-  }),
-  apiVersion: z.string().regex(/^[A-Za-z0-9][A-Za-z0-9._-]{0,127}$/).optional(),
-}).strict();
-const configuredModelSchema = z.object({
-  id: modelId,
-  label: z.string().min(1).max(128).refine((value) => value.trim() === value && !/\p{Cc}/u.test(value)),
-  litellm: z.object({
-    provider: z.string().regex(/^[A-Za-z0-9][A-Za-z0-9._-]{0,63}$/),
-    model: z.string().regex(/^[A-Za-z0-9][A-Za-z0-9._:/-]{0,255}$/),
-    disableThinking: z.literal(true).optional(),
-    endpoint: endpointSchema.optional(),
-  }).strict(),
-  apiKeyEnv: apiKeyEnvironment.optional(),
-}).strict().superRefine((value, context) => {
-  if (value.apiKeyEnv === undefined && value.litellm.endpoint === undefined) {
-    context.addIssue({
-      code: z.ZodIssueCode.custom,
-      path: ["apiKeyEnv"],
-      message: "keyless models require an explicit endpoint",
-    });
-  }
-  if (value.litellm.disableThinking === true && value.litellm.endpoint === undefined) {
-    context.addIssue({
-      code: z.ZodIssueCode.custom,
-      path: ["litellm", "disableThinking"],
-      message: "thinking may be disabled only for an explicit endpoint",
-    });
-  }
-});
-const metadataGenerationSchema = z.object({
-  default: modelId.optional(),
-  models: z.array(configuredModelSchema).max(64).default([]),
-}).strict();
-const installationSchema = z.object({
-  metadataGeneration: metadataGenerationSchema.optional(),
-}).passthrough();
+import { loadSecretBundle } from "../config/secret-bundle.js";
+import { loadRuntimeModelCatalog } from "../models/runtime-model-catalog.js";
 
 export interface MetadataGenerationModelChoice {
   id: string;
@@ -86,7 +28,6 @@ export class MetadataGenerationModelUnavailableError extends Error {
   }
 }
 
-/** The complete interface callers need: safe discovery plus fail-closed runtime resolution. */
 export interface MetadataGenerationModels {
   catalog(): MetadataGenerationModelCatalog;
   resolve(selection: string): ResolvedMetadataGenerationModel;
@@ -96,140 +37,78 @@ class RestartLoadedMetadataGenerationModels implements MetadataGenerationModels
   readonly #models: ReadonlyMap<string, ResolvedMetadataGenerationModel>;
   readonly #catalog: MetadataGenerationModelCatalog;
 
-  constructor(
-    models: ReadonlyMap<string, ResolvedMetadataGenerationModel> = new Map(),
-    defaultModel: string | null = null,
-    choices: MetadataGenerationModelChoice[] = [],
-  ) {
+  constructor(models: ReadonlyMap<string, ResolvedMetadataGenerationModel>, defaultModel: string | null) {
     this.#models = models;
     this.#catalog = {
-      models: choices.map((choice) => ({ ...choice })),
+      models: [...models.values()].map(({ id }) => ({ id, label: id })),
       default: defaultModel,
     };
   }
 
   catalog(): MetadataGenerationModelCatalog {
-    return {
-      models: this.#catalog.models.map((choice) => ({ ...choice })),
-      default: this.#catalog.default,
-    };
+    return { models: this.#catalog.models.map((choice) => ({ ...choice })), default: this.#catalog.default };
   }
 
   resolve(selection: string): ResolvedMetadataGenerationModel {
-    const model = typeof selection === "string" ? this.#models.get(selection) : undefined;
+    const model = this.#models.get(selection);
     if (!model) throw new MetadataGenerationModelUnavailableError();
     return model;
   }
 }
 
-function invalid(message = "metadata-generation configuration is invalid"): Error {
+function invalid(message = "metadata-generation runtime catalog is invalid"): Error {
   return new Error(message);
 }
 
-function protectedInstallationStat(file: string, info: Stats): boolean {
-  const mode = info.mode & 0o777;
-  if (!info.isFile() || info.isSymbolicLink() || info.nlink !== 1
-    || info.size < 1 || info.size > MAX_INSTALLATION_BYTES) return false;
-  if (file === RUNTIME_INSTALLATION_FILE && info.uid === 0 && mode === 0o444) return true;
-  return info.uid === (process.getuid?.() ?? info.uid) && (mode === 0o400 || mode === 0o600);
-}
-
-function readProtectedInstallation(file: string): string {
-  let descriptor: number | undefined;
-  try {
-    const before = lstatSync(file);
-    if (!protectedInstallationStat(file, before)) throw new Error("unavailable");
-    descriptor = openSync(file, constants.O_RDONLY | constants.O_NOFOLLOW);
-    const opened = fstatSync(descriptor);
-    if (!protectedInstallationStat(file, opened)
-      || before.dev !== opened.dev || before.ino !== opened.ino) throw new Error("unavailable");
-    const source = readFileSync(descriptor, "utf8");
-    const after = fstatSync(descriptor);
-    const current = lstatSync(file);
-    if (!protectedInstallationStat(file, after) || !protectedInstallationStat(file, current)
-      || opened.dev !== after.dev || opened.ino !== after.ino
-      || opened.dev !== current.dev || opened.ino !== current.ino) throw new Error("unavailable");
-    return source;
-  } finally {
-    if (descriptor !== undefined) try { closeSync(descriptor); } catch { /* sanitized below */ }
-  }
-}
-
-function readInstallation(file: string): unknown {
-  try {
-    const documents = parseAllDocuments(readProtectedInstallation(file), { uniqueKeys: true });
-    if (documents.length !== 1) throw invalid("metadata-generation installation must contain one YAML document");
-    const document = documents[0];
-    if (document.errors.length > 0 || document.warnings.length > 0) {
-      throw invalid("metadata-generation installation contains invalid YAML");
-    }
-    return document.toJSON();
-  } catch (error) {
-    if (error instanceof Error && error.message.startsWith("metadata-generation")) throw error;
-    throw invalid("metadata-generation installation is unavailable");
-  }
-}
-
 export function loadMetadataGenerationModels(options: {
-  installationFile?: string;
+  catalogFile?: string;
   secretsFile?: string;
 }): MetadataGenerationModels {
-  if (!options.installationFile) return new RestartLoadedMetadataGenerationModels();
-  const installation = installationSchema.safeParse(readInstallation(options.installationFile));
-  if (!installation.success) throw invalid();
-  const configured = installation.data.metadataGeneration;
-  if (!configured || configured.models.length === 0) {
-    if (configured?.default !== undefined) throw invalid("metadata-generation default does not identify a configured model");
-    return new RestartLoadedMetadataGenerationModels();
-  }
-  if (!configured.default) throw invalid("metadata-generation default is required when models are configured");
+  const catalog = loadRuntimeModelCatalog(options.catalogFile);
+  const configured = catalog.metadataModels();
+  if (configured.length === 0) return new RestartLoadedMetadataGenerationModels(new Map(), null);
 
-  const seen = new Set<string>();
-  for (const model of configured.models) {
-    if (seen.has(model.id)) throw invalid(`metadata-generation model id "${model.id}" is duplicated`);
-    seen.add(model.id);
-  }
-  if (!seen.has(configured.default)) {
-    throw invalid(`metadata-generation default "${configured.default}" is not configured`);
-  }
-  const requiresSecrets = configured.models.some((model) => model.apiKeyEnv !== undefined);
+  const requiresSecrets = configured.some((model) => model.authentication.mode === "secret_env");
   let secrets: ReadonlyMap<string, string> = new Map();
   if (requiresSecrets) {
     if (!options.secretsFile) throw invalid("metadata-generation keyed models require THT_SECRETS_FILE");
-    try {
-      secrets = loadSecretBundle(options.secretsFile);
-    } catch {
-      throw invalid("metadata-generation secrets are unavailable");
-    }
+    try { secrets = loadSecretBundle(options.secretsFile); }
+    catch { throw invalid("metadata-generation secrets are unavailable"); }
   }
+
   const models = new Map<string, ResolvedMetadataGenerationModel>();
-  for (const configuredModel of configured.models) {
+  const labels = new Map<string, string>();
+  for (const configuredModel of configured) {
+    const adapter = configuredModel.metadataAdapter;
+    if (!adapter || configuredModel.authentication.mode === "pi_auth") throw invalid();
+    const apiKeyEnv = configuredModel.authentication.apiKeyEnv;
     let apiKey: string | undefined;
-    if (configuredModel.apiKeyEnv !== undefined) {
-      apiKey = secrets.get(configuredModel.apiKeyEnv);
-      if (!apiKey) {
-        throw invalid(`metadata-generation model "${configuredModel.id}" secret "${configuredModel.apiKeyEnv}" is missing`);
-      }
+    if (configuredModel.authentication.mode === "secret_env") {
+      if (!apiKeyEnv) throw invalid();
+      apiKey = secrets.get(apiKeyEnv);
+      if (!apiKey) throw invalid(`metadata-generation model "${configuredModel.id}" secret "${apiKeyEnv}" is missing`);
       if (apiKey.length > 16 * 1024 || /\s/u.test(apiKey)) {
-        throw invalid(`metadata-generation model "${configuredModel.id}" secret "${configuredModel.apiKeyEnv}" is unusable`);
+        throw invalid(`metadata-generation model "${configuredModel.id}" secret "${apiKeyEnv}" is unusable`);
       }
     }
+    labels.set(configuredModel.id, configuredModel.label);
     models.set(configuredModel.id, Object.freeze({
       id: configuredModel.id,
-      provider: configuredModel.litellm.provider,
-      model: configuredModel.litellm.model,
-      ...(configuredModel.litellm.disableThinking === true ? { disableThinking: true as const } : {}),
-      ...(configuredModel.litellm.endpoint === undefined
-        ? {}
-        : { endpoint: Object.freeze({ ...configuredModel.litellm.endpoint }) }),
-      ...(configuredModel.apiKeyEnv === undefined
-        ? {}
-        : { apiKeyEnv: configuredModel.apiKeyEnv, apiKey }),
+      provider: adapter.litellmProvider,
+      model: configuredModel.upstreamModel,
+      ...(configuredModel.metadataGeneration?.disableThinking === true
+        ? { disableThinking: true as const } : {}),
+      ...(configuredModel.endpoint ? { endpoint: Object.freeze({ ...configuredModel.endpoint }) } : {}),
+      ...(apiKeyEnv ? { apiKeyEnv, apiKey } : {}),
     }));
   }
-  return new RestartLoadedMetadataGenerationModels(
-    models,
-    configured.default,
-    configured.models.map(({ id, label }) => ({ id, label })),
-  );
+  const result = new RestartLoadedMetadataGenerationModels(models, catalog.defaultMetadataGeneration);
+  const safe = result.catalog();
+  return {
+    catalog: () => ({
+      default: safe.default,
+      models: safe.models.map((choice) => ({ ...choice, label: labels.get(choice.id) ?? choice.id })),
+    }),
+    resolve: (selection) => result.resolve(selection),
+  };
 }

backend/src/catalog/migrate.ts

@@ -12,6 +12,7 @@ import * as sensitiveDataFlagMigration from "./migrations/006_sensitive_data_fla
 import * as sensitiveDataSuggestionRunsMigration from "./migrations/007_sensitive_data_suggestion_runs.js";
 import * as catalogLogicalRelationshipsMigration from "./migrations/008_catalog_logical_relationships.js";
 import * as aiTokenUsageMigration from "./migrations/009_ai_token_usage.js";
+import * as canonicalModelIdsMigration from "./migrations/010_canonical_model_ids.js";
 
 const connectionString = process.env.THT_CATALOG_MIGRATOR_DATABASE_URL;
 const host = process.env.THT_CATALOG_DB_HOST;
@@ -46,6 +47,7 @@ const provider: MigrationProvider = {
       "007_sensitive_data_suggestion_runs": sensitiveDataSuggestionRunsMigration,
       "008_catalog_logical_relationships": catalogLogicalRelationshipsMigration,
       "009_ai_token_usage": aiTokenUsageMigration,
+      "010_canonical_model_ids": canonicalModelIdsMigration,
     };
   },
 };

backend/src/catalog/migrations/010_canonical_model_ids.ts

@@ -0,0 +1,27 @@
+import { sql, type Kysely } from "kysely";
+import type { CatalogDatabase } from "../repository.js";
+
+const canonicalModelPattern = "^[a-z][a-z0-9._-]{0,63}/[A-Za-z0-9][A-Za-z0-9._:-]{0,255}$";
+const legacyModelPattern = "^[a-z][a-z0-9._-]{0,63}$";
+
+export async function up(db: Kysely<CatalogDatabase>): Promise<void> {
+  await sql.raw(`alter table description_generation_runs
+    drop constraint description_generation_runs_model_id_check,
+    add constraint description_generation_runs_model_id_check
+      check (model_id ~ '${canonicalModelPattern}')`).execute(db);
+  await sql.raw(`alter table sensitive_data_suggestion_runs
+    drop constraint sensitive_data_suggestion_runs_model_id_check,
+    add constraint sensitive_data_suggestion_runs_model_id_check
+      check (model_id ~ '${canonicalModelPattern}')`).execute(db);
+}
+
+export async function down(db: Kysely<CatalogDatabase>): Promise<void> {
+  await sql.raw(`alter table sensitive_data_suggestion_runs
+    drop constraint sensitive_data_suggestion_runs_model_id_check,
+    add constraint sensitive_data_suggestion_runs_model_id_check
+      check (model_id ~ '${legacyModelPattern}')`).execute(db);
+  await sql.raw(`alter table description_generation_runs
+    drop constraint description_generation_runs_model_id_check,
+    add constraint description_generation_runs_model_id_check
+      check (model_id ~ '${legacyModelPattern}')`).execute(db);
+}

backend/src/config.ts

@@ -32,6 +32,7 @@ export interface AppConfig {
   piManagementTimeoutMs: number;
   secretsFile?: string;
   installationConfigFile?: string;
+  modelCatalogFile?: string;
   piAuthFile?: string;
   secretFiles: Readonly<Record<string, string | undefined>>;
   modelApiKeyFile?: string;
@@ -50,6 +51,7 @@ export interface AppConfig {
   workspaceSecretRuntimeRoot: string;
   internalQdrantUrl: string;
   internalEmbeddingUrl: string;
+  internalEmbeddingId: string;
   internalEmbeddingModel: string;
   internalEmbeddingDimensions: number;
 }
@@ -189,6 +191,21 @@ function positiveDimension(value: string | undefined, fallback: number): number
   return parsed;
 }
 
+function internalEmbeddingIdentity(
+  identityValue: string | undefined,
+  modelValue: string | undefined,
+): { id: string; model: string } {
+  const id = identityValue ?? "ollama/qwen3-embedding:0.6b";
+  if (!/^ollama\/[A-Za-z0-9][A-Za-z0-9._:-]{0,255}$/.test(id)) {
+    throw new Error("internal embedding identity configuration is invalid");
+  }
+  const model = id.slice(id.indexOf("/") + 1);
+  if (modelValue !== undefined && modelValue !== model) {
+    throw new Error("internal embedding model does not match its canonical identity");
+  }
+  return { id, model };
+}
+
 function catalogDatabase(env: Record<string, string | undefined>): CatalogConnectionConfig | undefined {
   const value = env.THT_CATALOG_DATABASE_URL;
   if (value !== undefined) {
@@ -330,6 +347,13 @@ export function loadConfig(
     || installationConfigFile.includes("\0")
     || !path.isAbsolute(installationConfigFile)
   )) throw new Error("installation configuration is invalid");
+  const modelCatalogFile = env.THT_MODEL_CATALOG_FILE;
+  if (modelCatalogFile !== undefined && (
+    modelCatalogFile.trim() !== modelCatalogFile
+    || modelCatalogFile.length === 0
+    || modelCatalogFile.includes("\0")
+    || !path.isAbsolute(modelCatalogFile)
+  )) throw new Error("runtime model catalog configuration is invalid");
   const piAuthFile = env.THT_PI_AUTH_FILE;
   if (piAuthFile !== undefined && (
     piAuthFile.trim() !== piAuthFile || piAuthFile.length === 0 || piAuthFile.includes("\0")
@@ -391,6 +415,10 @@ export function loadConfig(
     "internal embedding URL",
     ["embedding", "localhost"],
   );
+  const internalEmbedding = internalEmbeddingIdentity(
+    env.THT_INTERNAL_EMBEDDING_ID,
+    env.THT_INTERNAL_EMBEDDING_MODEL,
+  );
   return {
     host: env.HOST ?? "127.0.0.1",
     port: Number(env.PORT ?? 8787),
@@ -404,7 +432,7 @@ export function loadConfig(
     publicExposure,
     sessionStorage,
     catalogDatabase: catalogDatabase(env),
-    defaults: { provider: env.PI_PROVIDER, model: env.PI_MODEL, thinking: env.PI_THINKING },
+    defaults: { thinking: env.PI_THINKING },
     maxPiProcesses: Number(env.MAX_PI_PROCESSES ?? 4),
     settingsFile,
     maintenanceFile: env.THT_MAINTENANCE_FILE ?? path.join(path.dirname(settingsFile), "maintenance.json"),
@@ -413,6 +441,7 @@ export function loadConfig(
     piManagementTimeoutMs: piManagementTimeout(env.PI_MANAGEMENT_TIMEOUT_MS),
     secretsFile,
     installationConfigFile,
+    modelCatalogFile,
     piAuthFile,
     secretFiles,
     modelApiKeyFile,
@@ -425,7 +454,8 @@ export function loadConfig(
     workspaceSecretRuntimeRoot,
     internalQdrantUrl,
     internalEmbeddingUrl,
-    internalEmbeddingModel: env.THT_INTERNAL_EMBEDDING_MODEL ?? "qwen3-embedding:0.6b",
+    internalEmbeddingId: internalEmbedding.id,
+    internalEmbeddingModel: internalEmbedding.model,
     internalEmbeddingDimensions: positiveDimension(env.THT_INTERNAL_EMBEDDING_DIMENSIONS, 1024),
   };
 }

backend/src/config/secret-bundle.ts

@@ -8,7 +8,7 @@ import {
   isUsableAuthenticationSecret,
 } from "../auth/secret-policy.js";
 
-/** Credential names that metadata-generation model entries may reference. */
+/** Credential names that Installation Model Catalog providers may reference. */
 export const METADATA_GENERATION_SECRET_KEYS = Object.freeze([
   "THT_METADATA_API_KEY", "ANTHROPIC_API_KEY", "AZURE_API_KEY", "GEMINI_API_KEY",
   "DEEPSEEK_API_KEY", "OPENAI_API_KEY", "OPENROUTER_API_KEY", "ZAI_API_KEY",

backend/src/models/runtime-model-catalog.ts

@@ -0,0 +1,161 @@
+import {
+  closeSync, constants, fstatSync, lstatSync, openSync, readFileSync, type Stats,
+} from "node:fs";
+import { z } from "zod";
+
+const MAX_CATALOG_BYTES = 1024 * 1024;
+const RUNTIME_CATALOG_FILE = "/run/thothii-model-catalog/catalog.json";
+const canonicalId = z.string().regex(/^[a-z][a-z0-9._-]{0,63}\/[A-Za-z0-9][A-Za-z0-9._:-]{0,255}$/);
+const secretBundleKey = /^[A-Z][A-Z0-9_]{0,63}$/;
+
+const endpointSchema = z.object({
+  baseUrl: z.string().url(),
+  apiVersion: z.string().optional(),
+}).strict();
+
+const authenticationSchema = z.object({
+  mode: z.enum(["secret_env", "pi_auth", "none"]),
+  apiKeyEnv: z.string().optional(),
+}).strict();
+
+const runtimeModelSchema = z.object({
+  id: canonicalId,
+  provider: z.string().min(1),
+  model: z.string().min(1),
+  label: z.string().min(1),
+  upstreamModel: z.string().min(1),
+  endpoint: endpointSchema.optional(),
+  authentication: authenticationSchema,
+  sessionAdapter: z.object({ mode: z.enum(["pi_builtin", "openai_compatible"]) }).strict().optional(),
+  metadataAdapter: z.object({ litellmProvider: z.string().min(1) }).strict().optional(),
+  session: z.object({
+    reasoning: z.boolean(),
+    input: z.array(z.string()).optional(),
+    cost: z.object({
+      input: z.number(), output: z.number(), cacheRead: z.number(), cacheWrite: z.number(),
+    }).strict().optional(),
+    contextWindow: z.number().int().positive().optional(),
+    maxTokens: z.number().int().positive().optional(),
+    compatibility: z.object({
+      supportsDeveloperRole: z.boolean(),
+      supportsReasoningEffort: z.boolean(),
+      supportsStore: z.boolean(),
+      maxTokensField: z.string().optional(),
+    }).strict().optional(),
+  }).strict().optional(),
+  metadataGeneration: z.object({ disableThinking: z.boolean() }).strict().optional(),
+}).strict();
+
+const catalogSchema = z.object({
+  schemaVersion: z.literal(1),
+  defaultSession: canonicalId,
+  defaultMetadataGeneration: canonicalId.optional(),
+  embedding: z.object({ id: canonicalId, dimensions: z.number().int().positive() }).strict(),
+  models: z.array(runtimeModelSchema).max(64),
+}).strict();
+
+export type RuntimeModel = z.infer<typeof runtimeModelSchema>;
+
+export interface RuntimeModelCatalog {
+  readonly defaultSession: string | null;
+  readonly defaultMetadataGeneration: string | null;
+  readonly embedding: Readonly<{ id: string; dimensions: number }> | null;
+  sessionModels(): readonly RuntimeModel[];
+  metadataModels(): readonly RuntimeModel[];
+  hasSession(id: string): boolean;
+}
+
+class RestartLoadedRuntimeModelCatalog implements RuntimeModelCatalog {
+  readonly defaultSession: string | null;
+  readonly defaultMetadataGeneration: string | null;
+  readonly embedding: Readonly<{ id: string; dimensions: number }> | null;
+  readonly #sessions: readonly RuntimeModel[];
+  readonly #metadata: readonly RuntimeModel[];
+  readonly #sessionIds: ReadonlySet<string>;
+
+  constructor(catalog?: z.infer<typeof catalogSchema>) {
+    this.defaultSession = catalog?.defaultSession ?? null;
+    this.defaultMetadataGeneration = catalog?.defaultMetadataGeneration ?? null;
+    this.embedding = catalog ? Object.freeze({ ...catalog.embedding }) : null;
+    this.#sessions = Object.freeze((catalog?.models ?? []).filter((model) => model.session !== undefined));
+    this.#metadata = Object.freeze((catalog?.models ?? []).filter((model) => model.metadataGeneration !== undefined));
+    this.#sessionIds = new Set(this.#sessions.map((model) => model.id));
+  }
+
+  sessionModels(): readonly RuntimeModel[] { return this.#sessions.map((model) => ({ ...model })); }
+  metadataModels(): readonly RuntimeModel[] { return this.#metadata.map((model) => ({ ...model })); }
+  hasSession(id: string): boolean { return this.#sessionIds.has(id); }
+}
+
+function protectedCatalogStat(file: string, info: Stats): boolean {
+  const mode = info.mode & 0o777;
+  if (!info.isFile() || info.isSymbolicLink() || info.nlink !== 1
+    || info.size < 1 || info.size > MAX_CATALOG_BYTES) return false;
+  if (file === RUNTIME_CATALOG_FILE && info.uid === 0 && (mode === 0o444 || mode === 0o644)) return true;
+  return info.uid === (process.getuid?.() ?? info.uid) && (mode === 0o400 || mode === 0o600 || mode === 0o644);
+}
+
+function readProtectedCatalog(file: string): unknown {
+  let descriptor: number | undefined;
+  try {
+    const before = lstatSync(file);
+    if (!protectedCatalogStat(file, before)) throw new Error("runtime model catalog is unavailable");
+    descriptor = openSync(file, constants.O_RDONLY | constants.O_NOFOLLOW);
+    const opened = fstatSync(descriptor);
+    if (!protectedCatalogStat(file, opened)
+      || before.dev !== opened.dev || before.ino !== opened.ino) throw new Error("runtime model catalog is unavailable");
+    const source = readFileSync(descriptor, "utf8");
+    const after = fstatSync(descriptor);
+    const current = lstatSync(file);
+    if (!protectedCatalogStat(file, after) || !protectedCatalogStat(file, current)
+      || opened.dev !== after.dev || opened.ino !== after.ino
+      || opened.dev !== current.dev || opened.ino !== current.ino) throw new Error("runtime model catalog is unavailable");
+    return JSON.parse(source);
+  } catch {
+    throw new Error("runtime model catalog is unavailable");
+  } finally {
+    if (descriptor !== undefined) try { closeSync(descriptor); } catch { /* sanitized above */ }
+  }
+}
+
+export function loadRuntimeModelCatalog(file?: string): RuntimeModelCatalog {
+  if (!file) return new RestartLoadedRuntimeModelCatalog();
+  const parsed = catalogSchema.safeParse(readProtectedCatalog(file));
+  if (!parsed.success) throw new Error("runtime model catalog is invalid");
+  if (parsed.data.models.some((model) => !validRuntimeModel(model))) {
+    throw new Error("runtime model catalog is invalid");
+  }
+  const ids = new Set(parsed.data.models.map((model) => model.id));
+  if (ids.size !== parsed.data.models.length) throw new Error("runtime model catalog contains duplicate models");
+  const sessions = parsed.data.models.filter((model) => model.session !== undefined).map((model) => model.id);
+  const metadata = parsed.data.models.filter((model) => model.metadataGeneration !== undefined).map((model) => model.id);
+  if (!sessions.includes(parsed.data.defaultSession)) throw new Error("runtime model catalog session default is invalid");
+  if ((metadata.length > 0) !== (parsed.data.defaultMetadataGeneration !== undefined)
+    || (parsed.data.defaultMetadataGeneration !== undefined
+      && !metadata.includes(parsed.data.defaultMetadataGeneration))) {
+    throw new Error("runtime model catalog metadata default is invalid");
+  }
+  return new RestartLoadedRuntimeModelCatalog(parsed.data);
+}
+
+function validRuntimeModel(model: RuntimeModel): boolean {
+  if ((model.session !== undefined) !== (model.sessionAdapter !== undefined)) return false;
+  if ((model.metadataGeneration !== undefined) !== (model.metadataAdapter !== undefined)) return false;
+  switch (model.authentication.mode) {
+    case "secret_env":
+      return model.authentication.apiKeyEnv !== undefined
+        && secretBundleKey.test(model.authentication.apiKeyEnv);
+    case "pi_auth":
+      return model.authentication.apiKeyEnv === undefined
+        && model.metadataGeneration === undefined
+        && model.sessionAdapter?.mode === "pi_builtin";
+    case "none":
+      return model.authentication.apiKeyEnv === undefined && model.endpoint !== undefined;
+  }
+}
+
+export function splitCanonicalModelId(id: string): { provider: string; model: string } {
+  const slash = id.indexOf("/");
+  if (slash <= 0 || slash === id.length - 1) throw new Error("model identity is invalid");
+  return { provider: id.slice(0, slash), model: id.slice(slash + 1) };
+}

backend/src/operator-command.ts

@@ -8,8 +8,8 @@ import { join } from "node:path";
 import { loadConfig, type AppConfig } from "./config.js";
 import { rolesToPermissions } from "./auth/config.js";
 import type { PrincipalContext } from "./auth/principal.js";
-import { createPiModelLister } from "./pi/list-models.js";
 import { createPiManagement } from "./pi/management.js";
+import { loadRuntimeModelCatalog } from "./models/runtime-model-catalog.js";
 import { effectiveSettings } from "./routes/settings.js";
 import { MaintenanceBarrier } from "./runtime/maintenance-gate.js";
 import { loadSettings } from "./settings/settings-store.js";
@@ -19,7 +19,7 @@ import { WorkspaceSecretStore } from "./workspaces/secret-store.js";
 
 type OperatorAction = "maintenance-activate" | "maintenance-deactivate" | "maintenance-status"
   | "session-inventory" | "workflow-doctor" | "workspace-integrity"
-  | "pi-options" | "pi-test" | "effective-settings";
+  | "pi-test" | "effective-settings";
 
 const lifecyclePrincipal: PrincipalContext = {
   issuer: "tht-operator-command",
@@ -110,9 +110,11 @@ export async function runOperatorAction(
   if (action === "session-inventory") return await sessionInventory(config);
   if (action === "workflow-doctor") return await workflowDiagnostics(config);
   if (action === "workspace-integrity") return await workspaceIntegrity(config);
-  if (action === "effective-settings") return effectiveSettings(config, loadSettings(config));
-  const service = createPiManagement(config, { listModels: createPiModelLister(config) });
-  if (action === "pi-options") return await service.options();
+  const modelCatalog = loadRuntimeModelCatalog(config.modelCatalogFile);
+  if (action === "effective-settings") {
+    return effectiveSettings(config, loadSettings(config), modelCatalog);
+  }
+  const service = createPiManagement(config, { modelCatalog });
   if (action === "pi-test") return await service.test();
   throw new Error("unsupported operator action");
 }
@@ -121,7 +123,7 @@ async function main(): Promise<void> {
   const action = process.argv[2] as OperatorAction | undefined;
   if (!action || ![
     "maintenance-activate", "maintenance-deactivate", "maintenance-status", "session-inventory",
-    "workflow-doctor", "workspace-integrity", "pi-options", "pi-test", "effective-settings",
+    "workflow-doctor", "workspace-integrity", "pi-test", "effective-settings",
   ].includes(action)) throw new Error("invalid operator action");
   const result = await runOperatorAction(action, loadConfig(process.env));
   process.stdout.write(`${JSON.stringify(result)}\n`);

backend/src/pi/list-models.ts

@@ -18,6 +18,8 @@ export interface PiModel {
   reasoning: boolean;
 }
 
+export type ListModelsFn = () => Promise<PiModel[]>;
+
 interface Opts {
   spawnFn?: (
     command: string,
@@ -36,7 +38,7 @@ interface Opts {
  * configured) via an ephemeral `pi --mode rpc` process. Result is cached for
  * `ttlMs`. The returned function rejects on timeout/error; callers degrade.
  */
-export function createPiModelLister(cfg: AppConfig, opts: Opts = {}): () => Promise<PiModel[]> {
+export function createPiModelLister(cfg: AppConfig, opts: Opts = {}): ListModelsFn {
   const ttlMs = opts.ttlMs ?? 60_000;
   const now = opts.nowMs ?? (() => Date.now());
   const spawnFn = opts.spawnFn ?? nodeSpawn;

backend/src/pi/management.ts

@@ -2,12 +2,11 @@ import { execFile as nodeExecFile } from "node:child_process";
 import { promisify } from "node:util";
 import type { AppConfig } from "../config.js";
 import { secretValue } from "../config/secret-bundle.js";
+import { loadSettings, type Settings } from "../settings/settings-store.js";
 import {
-  loadSettings,
-  saveSettings,
-  type Settings,
-} from "../settings/settings-store.js";
-import type { PiModel } from "./list-models.js";
+  splitCanonicalModelId,
+  type RuntimeModelCatalog,
+} from "../models/runtime-model-catalog.js";
 import {
   configuredPiProviderApiKey,
   PI_MANAGED_CONFIG_ERROR_MESSAGE,
@@ -45,13 +44,6 @@ export interface PiStatus {
   message?: string;
 }
 
-export interface PiOptions {
-  providers: string[];
-  models: Array<{ provider: string; id: string }>;
-  reasoning: PiReasoning[];
-  checkedAt: string;
-}
-
 export interface PiTestResult {
   ready: boolean;
   checkedAt: string;
@@ -76,15 +68,13 @@ export type PiExecFile = (
 
 export interface PiManagementService {
   status(): Promise<PiStatus>;
-  options(): Promise<PiOptions>;
-  configure(value: PiInstallationConfig): Promise<PiInstallationConfig & { updatedAt: string }>;
   test(): Promise<PiTestResult>;
   logs(): Promise<PiLogs>;
 }
 
 export class PiManagementError extends Error {
   constructor(
-    public readonly code: "pi_management_invalid_config" | "pi_management_unavailable" | "pi_management_write_failed",
+    public readonly code: "pi_management_unavailable",
     message: string,
   ) {
     super(message);
@@ -93,10 +83,9 @@ export class PiManagementError extends Error {
 
 interface PiManagementDeps {
   execute?: PiExecFile;
-  listModels: () => Promise<PiModel[]>;
+  modelCatalog: RuntimeModelCatalog;
   smokeProvider?: PiProviderSmoke;
   readSettings?: () => Settings;
-  saveSettings?: (settings: Settings) => Settings;
   readLogs?: () => string | Promise<string>;
   credentialStatus?: (provider: string | undefined) => PiCredentialStatus;
   now?: () => Date;
@@ -111,54 +100,36 @@ export function createPiManagement(config: AppConfig, deps: PiManagementDeps): P
   };
   const execute = deps.execute ?? defaultExecFile;
   const readSettings = deps.readSettings ?? (() => loadSettings(config));
-  const persistSettings = deps.saveSettings ?? ((settings) => saveSettings(config, settings));
   const readLogs = deps.readLogs ?? (() => diagnostics.join("\n"));
-  const smokeProvider = deps.smokeProvider ?? createPiProviderSmoke(config);
+  const smokeProvider = deps.smokeProvider ?? createPiProviderSmoke(config, {
+    modelCatalog: deps.modelCatalog,
+  });
   const credentialStatus = deps.credentialStatus ?? ((provider: string | undefined) => {
     try {
+      const model = deps.modelCatalog.defaultSession
+        ? deps.modelCatalog.sessionModels().find((entry) => entry.id === deps.modelCatalog.defaultSession)
+        : undefined;
+      const credentialName = model?.authentication.mode === "secret_env"
+        ? model.authentication.apiKeyEnv
+        : undefined;
+      const configuredApiKey = configuredPiProviderApiKey(
+        readConfiguredPiAgentFile("models.json", true),
+        provider,
+      ) ?? (credentialName ? `$${credentialName}` : undefined);
       return piProviderCredentialStatus({
         provider,
         authProviders: loadPiAuthProviders(),
-        resolveCredentialValue: () => secretValue(config, "THT_MODEL_API_KEY"),
+        resolveCredentialValue: () => credentialName
+          ? secretValue(config, credentialName)
+          : config.modelCatalogFile ? undefined : secretValue(config, "THT_MODEL_API_KEY"),
         credentialFile: config.modelApiKeyFile,
-        configuredApiKey: configuredPiProviderApiKey(
-          readConfiguredPiAgentFile("models.json", true),
-          provider,
-        ),
+        configuredApiKey,
       });
     } catch {
       return "missing";
     }
   });
 
-  const closedOptions = async (): Promise<Omit<PiOptions, "checkedAt">> => {
-    let listed: PiModel[];
-    try {
-      listed = await deps.listModels();
-    } catch (error) {
-      if (isPiManagedConfigError(error)) {
-        throw new PiManagementError("pi_management_unavailable", PI_MANAGED_CONFIG_ERROR_MESSAGE);
-      }
-      throw new PiManagementError("pi_management_unavailable", "Pi model choices are unavailable");
-    }
-    const models: Array<{ provider: string; id: string }> = [];
-    const providers: string[] = [];
-    const seenModels = new Set<string>();
-    const seenProviders = new Set<string>();
-    for (const model of listed) {
-      if (!isChoice(model?.provider) || !isChoice(model?.id)) continue;
-      const key = `${model.provider}\u0000${model.id}`;
-      if (seenModels.has(key)) continue;
-      seenModels.add(key);
-      models.push({ provider: model.provider, id: model.id });
-      if (!seenProviders.has(model.provider)) {
-        seenProviders.add(model.provider);
-        providers.push(model.provider);
-      }
-    }
-    return { providers, models, reasoning: [...REASONING_CHOICES] };
-  };
-
   const version = async (timeoutMs = config.piManagementTimeoutMs): Promise<string> => {
     let output: { stdout: string; stderr: string };
     try {
@@ -180,12 +151,12 @@ export function createPiManagement(config: AppConfig, deps: PiManagementDeps): P
 
   const installationConfig = (): PiInstallationConfig => {
     const settings = readSettings();
-    const provider = config.defaults.provider ?? settings.provider;
-    const model = config.defaults.model ?? settings.model;
     const reasoning = config.defaults.thinking ?? settings.thinking;
+    const selected = deps.modelCatalog.defaultSession
+      ? splitCanonicalModelId(deps.modelCatalog.defaultSession)
+      : undefined;
     return {
-      ...(isChoice(provider) ? { provider } : {}),
-      ...(isChoice(model) ? { model } : {}),
+      ...(selected ? selected : {}),
       ...(isReasoning(reasoning) ? { reasoning } : {}),
     };
   };
@@ -206,28 +177,6 @@ export function createPiManagement(config: AppConfig, deps: PiManagementDeps): P
       }
     },
 
-    async options(): Promise<PiOptions> {
-      const choices = await closedOptions();
-      return { ...choices, checkedAt: now().toISOString() };
-    },
-
-    async configure(value: PiInstallationConfig): Promise<PiInstallationConfig & { updatedAt: string }> {
-      if (!isInstallationConfig(value)) {
-        throw new PiManagementError("pi_management_invalid_config", "Pi installation configuration is invalid");
-      }
-      const choices = await closedOptions();
-      if (!choices.models.some((model) => model.provider === value.provider && model.id === value.model)) {
-        throw new PiManagementError("pi_management_invalid_config", "Pi provider and model must be selected from available choices");
-      }
-      try {
-        persistSettings({ ...readSettings(), provider: value.provider, model: value.model, thinking: value.reasoning });
-      } catch {
-        throw new PiManagementError("pi_management_write_failed", "Pi installation configuration could not be saved");
-      }
-      addDiagnostic("Pi installation defaults updated");
-      return { ...value, updatedAt: now().toISOString() };
-    },
-
     async test(): Promise<PiTestResult> {
       const checkedAt = now().toISOString();
       const deadline = Date.now() + config.piManagementTimeoutMs;
@@ -293,24 +242,10 @@ async function defaultExecFile(command: string, args: string[], options: PiExecF
   return { stdout: String(result.stdout), stderr: String(result.stderr) };
 }
 
-function isChoice(value: unknown): value is string {
-  return typeof value === "string" && value.length > 0 && value.length <= 128 && value.trim() === value
-    && /^[A-Za-z0-9][A-Za-z0-9._/-]*$/u.test(value);
-}
-
 function isReasoning(value: unknown): value is PiReasoning {
   return typeof value === "string" && (REASONING_CHOICES as readonly string[]).includes(value);
 }
 
-function isInstallationConfig(value: unknown): value is Required<PiInstallationConfig> {
-  if (!value || typeof value !== "object" || Array.isArray(value)) return false;
-  const candidate = value as Record<string, unknown>;
-  if (Object.keys(candidate).length !== 3 || Object.keys(candidate).some((key) => !["provider", "model", "reasoning"].includes(key))) {
-    return false;
-  }
-  return isChoice(candidate.provider) && isChoice(candidate.model) && isReasoning(candidate.reasoning);
-}
-
 function isTimeout(error: unknown): boolean {
   return Boolean(
     error && typeof error === "object" && (

backend/src/pi/pi-process-manager.ts

@@ -11,6 +11,10 @@ import {
   configuredPiProviderApiKey,
   createPiRuntimeAgentSnapshot,
 } from "./managed-config.js";
+import {
+  loadRuntimeModelCatalog,
+  type RuntimeModelCatalog,
+} from "../models/runtime-model-catalog.js";
 
 export interface SessionRuntime {
   rpc: RpcClient;
@@ -42,23 +46,32 @@ export class PiProcessManager {
   private runtimes = new Map<string, SessionRuntime>();
   private agentSnapshotCleanups = new WeakMap<ChildProcessWithoutNullStreams, () => void>();
   private spawnFn: (
-    sessionId: string, author: string, provider: string | undefined, principal?: PrincipalContext,
-    runtimeConfigPath?: string,
+    sessionId: string, author: string, provider: string | undefined, model: string | undefined,
+    principal?: PrincipalContext, runtimeConfigPath?: string,
   ) => ChildProcessWithoutNullStreams;
   private loadAuthProviders: (agentDir: string) => ReadonlySet<string>;
+  private modelCatalog: RuntimeModelCatalog;
+  private modelCatalogConfigured: boolean;
 
   constructor(
     private cfg: AppConfig,
-    opts?: { spawnFn?: SpawnFn; authProviders?: (agentDir: string) => ReadonlySet<string> },
+    opts?: {
+      spawnFn?: SpawnFn;
+      authProviders?: (agentDir: string) => ReadonlySet<string>;
+      modelCatalog?: RuntimeModelCatalog;
+    },
   ) {
+    this.modelCatalog = opts?.modelCatalog ?? loadRuntimeModelCatalog(cfg.modelCatalogFile);
+    this.modelCatalogConfigured = cfg.modelCatalogFile !== undefined
+      || this.modelCatalog.defaultSession !== null;
     this.loadAuthProviders = opts?.authProviders
       ?? ((agentDir) => loadPiAuthProviders({ agentDir }));
     if (opts?.spawnFn) {
-      this.spawnFn = (sessionId, author, provider, principal, runtimeConfigPath) =>
-        this.spawnPi(opts.spawnFn!, sessionId, author, provider, principal, runtimeConfigPath);
+      this.spawnFn = (sessionId, author, provider, model, principal, runtimeConfigPath) =>
+        this.spawnPi(opts.spawnFn!, sessionId, author, provider, model, principal, runtimeConfigPath);
     } else {
-      this.spawnFn = (sessionId, author, provider, principal, runtimeConfigPath) =>
-        this.spawnPi(nodeSpawn, sessionId, author, provider, principal, runtimeConfigPath);
+      this.spawnFn = (sessionId, author, provider, model, principal, runtimeConfigPath) =>
+        this.spawnPi(nodeSpawn, sessionId, author, provider, model, principal, runtimeConfigPath);
     }
   }
 
@@ -71,7 +84,7 @@ export class PiProcessManager {
 
   private spawnPi(
     spawnFn: SpawnFn, sessionId: string, author: string, provider: string | undefined,
-    principal?: PrincipalContext, runtimeConfigPath?: string,
+    model: string | undefined, principal?: PrincipalContext, runtimeConfigPath?: string,
   ): ChildProcessWithoutNullStreams {
     // This is the final shared boundary for createFor(), spawnFor(), and resume(). Validate
     // before auth-provider inspection, then make Pi consume the exact copied bytes rather than
@@ -79,12 +92,23 @@ export class PiProcessManager {
     const agent = createPiRuntimeAgentSnapshot();
     let child: ChildProcessWithoutNullStreams | undefined;
     try {
+      const catalogModel = provider && model
+        ? this.modelCatalog.sessionModels()
+          .find((entry) => entry.provider === provider && entry.model === model)
+        : undefined;
+      const credentialName = catalogModel?.authentication.mode === "secret_env"
+        ? catalogModel.authentication.apiKeyEnv
+        : undefined;
+      const projectedApiKey = configuredPiProviderApiKey(agent.models, provider)
+        ?? (credentialName ? `$${credentialName}` : undefined);
       const env = buildPiChildEnv({
         provider,
         authProviders: this.loadAuthProviders(agent.agentDir),
-        credentialValue: secretValue(this.cfg, "THT_MODEL_API_KEY"),
+        credentialValue: credentialName
+          ? secretValue(this.cfg, credentialName)
+          : this.modelCatalogConfigured ? undefined : secretValue(this.cfg, "THT_MODEL_API_KEY"),
         credentialFile: this.cfg.modelApiKeyFile,
-        configuredApiKey: configuredPiProviderApiKey(agent.models, provider),
+        configuredApiKey: projectedApiKey,
         additions: { THT_SESSION: sessionId, THT_AUTHOR: author },
       });
       env.PI_CODING_AGENT_DIR = agent.agentDir;
@@ -162,9 +186,10 @@ export class PiProcessManager {
     }
     const author = o.author ?? "dev@local";
     const provider = canonicalPiProvider(o.provider ?? this.cfg.defaults.provider);
+    const model = o.model ?? this.cfg.defaults.model;
     let child: ChildProcessWithoutNullStreams;
     try {
-      child = this.spawnFn(sessionId, author, provider, o.principal, o.runtimeConfig?.path);
+      child = this.spawnFn(sessionId, author, provider, model, o.principal, o.runtimeConfig?.path);
     } catch (error) {
       o.runtimeConfig?.release();
       throw error;

backend/src/pi/provider-smoke.ts

@@ -17,6 +17,10 @@ import {
   readConfiguredPiAgentFile,
   validateDeclarativePiConfig,
 } from "./managed-config.js";
+import {
+  loadRuntimeModelCatalog,
+  type RuntimeModelCatalog,
+} from "../models/runtime-model-catalog.js";
 
 const SMOKE_PROMPT = "Provider health check. Reply with exactly OK.";
 const SMOKE_ARGS = [
@@ -49,6 +53,7 @@ interface ProviderSmokeOptions {
   authProviders?: () => ReadonlySet<string>;
   readAuthStore?: () => string;
   readModelsStore?: () => string | undefined;
+  modelCatalog?: RuntimeModelCatalog;
 }
 
 export function createPiProviderSmoke(
@@ -69,12 +74,24 @@ export function createPiProviderSmoke(
       const configuredModels = options.readModelsStore
         ? options.readModelsStore()
         : readConfiguredPiAgentFile("models.json", true);
+      const catalog = options.modelCatalog ?? loadRuntimeModelCatalog(config.modelCatalogFile);
+      const catalogConfigured = config.modelCatalogFile !== undefined
+        || catalog.defaultSession !== null;
+      const catalogModel = catalog.sessionModels()
+        .find((entry) => entry.provider === canonicalProvider && entry.model === model);
+      const credentialName = catalogModel?.authentication.mode === "secret_env"
+        ? catalogModel.authentication.apiKeyEnv
+        : undefined;
+      const projectedApiKey = configuredPiProviderApiKey(configuredModels, canonicalProvider)
+        ?? (credentialName ? `$${credentialName}` : undefined);
       const env = buildPiChildEnv({
         provider: canonicalProvider,
         authProviders: configuredAuthProviders,
-        credentialValue: secretValue(config, "THT_MODEL_API_KEY"),
+        credentialValue: credentialName
+          ? secretValue(config, credentialName)
+          : catalogConfigured ? undefined : secretValue(config, "THT_MODEL_API_KEY"),
         credentialFile: config.modelApiKeyFile,
-        configuredApiKey: configuredPiProviderApiKey(configuredModels, canonicalProvider),
+        configuredApiKey: projectedApiKey,
       });
       clearPrincipalEnvironment(env);
       delete env.THT_DATA_ROOT;

backend/src/routes/catalog-description-generation.ts

@@ -32,7 +32,7 @@ import {
 } from "../catalog/types.js";
 
 const idSchema = z.uuid();
-const modelIdSchema = z.string().regex(/^[a-z][a-z0-9._-]{0,63}$/);
+const modelIdSchema = z.string().regex(/^[a-z][a-z0-9._-]{0,63}\/[A-Za-z0-9][A-Za-z0-9._:-]{0,255}$/);
 const selectedTargetIdsSchema = z.array(idSchema).min(1);
 const suggestionSchema = z.discriminatedUnion("scope", [
   z.object({ modelId: modelIdSchema, scope: z.literal("all") }).strict(),

backend/src/routes/meta.ts

@@ -1,10 +1,8 @@
 import { readdirSync } from "node:fs";
 import { join } from "node:path";
 import type { FastifyInstance } from "fastify";
-import type { PiModel } from "../pi/list-models.js";
 import { isPrincipalContext, requirePermission } from "../auth/authorization.js";
-
-export type ListModelsFn = () => Promise<PiModel[]>;
+import type { RuntimeModelCatalog } from "../models/runtime-model-catalog.js";
 
 /**
  * List YAML workspace configs found in <harnessDir>/workspaces/*.yaml.
@@ -25,20 +23,17 @@ export function listWorkspaces(harnessDir: string): { name: string; file: string
 
 export function metaRoutes(
   app: FastifyInstance,
-  deps: { harnessDir: string; listModels?: ListModelsFn },
+  deps: { harnessDir: string; modelCatalog: RuntimeModelCatalog },
 ): void {
   app.get("/models", async (request, reply) => {
     if (!isPrincipalContext(requirePermission(request, reply, "session.use"))) return reply;
-    const fn = deps.listModels ?? (async () => []);
-    try {
-      return { models: await fn() };
-    } catch (error) {
-      app.log.warn({
-        component: "pi-model-list",
-        errorType: error instanceof Error ? error.name : typeof error,
-      }, "Pi model listing failed");
-      // Graceful fallback: Pi may not be running; don't crash the server.
-      return { models: [] as PiModel[] };
-    }
+    return {
+      models: deps.modelCatalog.sessionModels().map((entry) => ({
+        provider: entry.provider,
+        id: entry.model,
+        name: entry.label,
+        reasoning: entry.session?.reasoning ?? false,
+      })),
+    };
   });
 }

backend/src/routes/pi-management.ts

@@ -11,13 +11,6 @@ export function piManagementRoutes(
   deps: { service: PiManagementService },
 ): void {
   app.get("/pi-management/status", async (request, reply) => run(request, reply, deps, () => deps.service.status()));
-  app.get("/pi-management/options", async (request, reply) => run(request, reply, deps, () => deps.service.options()));
-  app.put("/pi-management/config", async (request, reply) => run(
-    request,
-    reply,
-    deps,
-    () => deps.service.configure((request.body ?? {}) as Record<string, unknown>),
-  ));
   app.post("/pi-management/test", async (request, reply) => run(request, reply, deps, () => deps.service.test()));
   app.get("/pi-management/logs", async (request, reply) => run(request, reply, deps, () => deps.service.logs()));
 }
@@ -38,8 +31,7 @@ async function run<T>(
     return await action();
   } catch (error) {
     if (error instanceof PiManagementError) {
-      const statusCode = error.code === "pi_management_invalid_config" ? 400 : 503;
-      return reply.code(statusCode).send({ code: error.code, error: error.message });
+      return reply.code(503).send({ code: error.code, error: error.message });
     }
     return reply.code(503).send({ code: "pi_management_unavailable", error: "Pi management is unavailable" });
   }

backend/src/routes/sessions.ts

@@ -6,12 +6,13 @@ import type { Settings } from "../settings/settings-store.js";
 import { getPrincipal } from "../auth/auth.js";
 import type { PrincipalContext } from "../auth/principal.js";
 import type { ReadinessManager } from "../runtime/readiness-manager.js";
-import type { ListModelsFn } from "./meta.js";
+import type { ListModelsFn } from "../pi/list-models.js";
 import type { WorkspaceRegistry } from "../workspaces/registry.js";
 import { validateOperationalWorkspace, type WorkspaceDescriptor } from "../workspaces/schema.js";
 import type { MaintenanceBarrier } from "../runtime/maintenance-gate.js";
 import { hasPermission, isPrincipalContext, requirePermission } from "../auth/authorization.js";
 import type { EffectiveRelationshipSnapshotProvider } from "../catalog/effective-relationship-snapshot.js";
+import { splitCanonicalModelId, type RuntimeModelCatalog } from "../models/runtime-model-catalog.js";
 
 const BOOTSTRAP_FAILURE_MESSAGE =
   "Session startup failed. Check configuration and connectivity, then Resume the session.";
@@ -43,6 +44,7 @@ export function sessionRoutes(
     maintenanceBarrier: MaintenanceBarrier;
     /** Optional only for narrow route-test stubs and installations without a Catalog database. */
     effectiveRelationships?: EffectiveRelationshipSnapshotProvider;
+    modelCatalog: RuntimeModelCatalog;
   },
 ) {
   const lifecycleTails = new Map<string, Promise<void>>();
@@ -358,7 +360,6 @@ export function sessionRoutes(
       let workspaceId: string | undefined;
       let workspaceRevision: string | undefined;
       let workspaceDescriptor: WorkspaceDescriptor | undefined;
-      let allowedModels: readonly string[] | undefined;
       if (requestedWorkspaceId) {
         try {
           const registry = d.workspaceRegistry as Partial<WorkspaceRegistry>;
@@ -378,7 +379,6 @@ export function sessionRoutes(
           workspaceId = resolved.revision.id;
           workspaceRevision = resolved.revision.commit;
           workspaceDescriptor = resolved.workspace;
-          allowedModels = resolved.workspace.llm_policy.allowed;
         } catch {
           return reply.code(409).send({
             error: WORKSPACE_REVISION_UNAVAILABLE_MESSAGE,
@@ -386,12 +386,17 @@ export function sessionRoutes(
           });
         }
       }
-      const provider = b.provider ?? s.provider;
-      const model = b.model ?? s.model;
+	  const requestedCanonical = b.provider && b.model ? `${b.provider}/${b.model}` : undefined;
+	  let selectedCanonical = requestedCanonical ?? d.modelCatalog.defaultSession;
+	  let modelWarning: string | undefined;
+	  if (selectedCanonical && d.modelCatalog.defaultSession && !d.modelCatalog.hasSession(selectedCanonical)) {
+	    selectedCanonical = d.modelCatalog.defaultSession;
+	    modelWarning = `Configured model ${requestedCanonical ?? "selection"} is unavailable; using ${selectedCanonical}.`;
+	  }
+	  const selected = selectedCanonical ? splitCanonicalModelId(selectedCanonical) : undefined;
+	  const provider = selected?.provider ?? b.provider;
+	  const model = selected?.model ?? b.model;
       const thinking = b.thinking ?? s.thinking;
-      if (allowedModels && provider && model && !allowedModels.includes(`${provider}/${model}`)) {
-        return reply.code(400).send({ error: "Selected model is not allowed by this workspace." });
-      }
       // A persisted session is resumable without keeping Pi alive. New work replaces every
       // runtime owned by this principal, while runtimes belonging to other users remain intact.
       // Optional chaining preserves the deliberately narrow manager stubs used by route tests.
@@ -490,7 +495,7 @@ export function sessionRoutes(
         ),
         () => d.mgr.start(id, rt, runtimeOptions),
       );
-      return { id };
+      return { id, ...(modelWarning ? { warning: modelWarning } : {}) };
     } finally {
       if (revisionLease && !manifestPersisted) {
         await revisionLease.abort().catch((error: unknown) => {
@@ -598,6 +603,10 @@ export function sessionRoutes(
         provider?: string; model?: string; thinking?: string;
         workspace_id?: string; workspace_revision?: string;
       };
+	  const savedCanonical = saved.provider && saved.model ? `${saved.provider}/${saved.model}` : "";
+	  if (d.modelCatalog.defaultSession && (!savedCanonical || !d.modelCatalog.hasSession(savedCanonical))) {
+	    return reply.code(503).send({ error: MODEL_UNAVAILABLE_MESSAGE, code: "model_unavailable" });
+	  }
       let workspaceConfigPath: string;
       let workspaceDescriptor: WorkspaceDescriptor | undefined;
       try {

backend/src/routes/settings.ts

@@ -1,17 +1,27 @@
 import type { FastifyInstance } from "fastify";
 import type { AppConfig } from "../config.js";
 import type { Settings } from "../settings/settings-store.js";
-import { listWorkspaces, type ListModelsFn } from "./meta.js";
+import { listWorkspaces } from "./meta.js";
 import type { PrincipalContext } from "../auth/principal.js";
 import { isPrincipalContext, requirePermission } from "../auth/authorization.js";
+import {
+  splitCanonicalModelId,
+  type RuntimeModelCatalog,
+} from "../models/runtime-model-catalog.js";
 
-/** Merge stored settings over env/first-workspace defaults. */
-export function effectiveSettings(cfg: AppConfig, stored: Settings): Settings {
+/** Merge only workspace and runtime-thinking preferences; model defaults belong to modelCatalog. */
+export function effectiveSettings(
+  cfg: AppConfig,
+  stored: Settings,
+  modelCatalog?: RuntimeModelCatalog,
+): Settings {
   const workspaces = listWorkspaces(cfg.harnessDir);
+  const selected = modelCatalog?.defaultSession
+    ? splitCanonicalModelId(modelCatalog.defaultSession)
+    : undefined;
   return {
     workspace: stored.workspace ?? workspaces[0]?.name,
-    provider: cfg.defaults.provider ?? stored.provider,
-    model: cfg.defaults.model ?? stored.model,
+    ...(selected ?? {}),
     thinking: cfg.defaults.thinking ?? stored.thinking,
   };
 }
@@ -19,7 +29,7 @@ export function effectiveSettings(cfg: AppConfig, stored: Settings): Settings {
 export function settingsRoutes(
   app: FastifyInstance,
   deps: {
-    cfg: AppConfig; listModels: ListModelsFn;
+    cfg: AppConfig;
     getSettings: (principal: PrincipalContext) => Promise<Settings>;
   },
 ): void {
@@ -37,22 +47,6 @@ export function settingsRoutes(
     const principal = requirePermission(req, reply, "settings.manage");
     if (!isPrincipalContext(principal)) return principal;
     const b = (req.body ?? {}) as Settings;
-    if (b.model) {
-      let available: { provider: string; id: string }[] = [];
-      try {
-        available = await deps.listModels();
-      } catch {
-        available = [];
-      }
-      // Only validate when Pi gave us a non-empty list; otherwise allow (degraded).
-      if (available.length > 0 && !available.some(
-        (candidate) => candidate.provider === b.provider && candidate.id === b.model,
-      )) {
-        return reply.code(400).send({
-          error: `Unknown model: ${b.provider ?? "unknown"}/${b.model}`,
-        });
-      }
-    }
     try {
       // Retain this endpoint as a validating compatibility surface for older clients, but do
       // not write anonymous users' choices to shared server storage.

backend/src/settings/settings-store.ts

@@ -13,6 +13,7 @@ import type { AppConfig } from "../config.js";
 
 export interface Settings {
   workspace?: string;
+  /** Legacy input fields are ignored when loading/evaluating installation settings. */
   provider?: string;
   model?: string;
   thinking?: string;
@@ -37,7 +38,13 @@ export function loadSettings(cfg: AppConfig): Settings {
   try {
     const raw = readFileSync(cfg.settingsFile, "utf8");
     const parsed = JSON.parse(raw);
-    if (parsed && typeof parsed === "object") return parsed as Settings;
+    if (parsed && typeof parsed === "object") {
+      const value = parsed as Record<string, unknown>;
+      return {
+        ...(typeof value.workspace === "string" ? { workspace: value.workspace } : {}),
+        ...(typeof value.thinking === "string" ? { thinking: value.thinking } : {}),
+      };
+    }
     return {};
   } catch {
     return {};

backend/src/tht/tht-runner.ts

@@ -598,7 +598,11 @@ export class ThtRunner {
     } catch {
       return { ok: false, code: "workspace_not_activatable" };
     }
-    const collection = descriptor.semantic_index.vector_store;
+    const collection = {
+      collection: descriptor.workspace.id,
+      dimensions: this.cfg.semanticRuntime.internalEmbeddingDimensions,
+      distance: "cosine" as const,
+    };
     const controller = new AbortController();
     const timer = setTimeout(() => controller.abort(), Math.max(1, timeoutSec) * 1000);
     try {

backend/src/workspace-maintenance.ts

@@ -238,6 +238,7 @@ function createProductionService(): WorkspacePreprocessingService {
   });
   return new WorkspacePreprocessingService({
     dataRoot: config.dataRoot ?? "/data",
+    embeddingDimensions: config.internalEmbeddingDimensions,
     httpPrivateHostAllowlist: (process.env.THT_EVIDENCE_PRIVATE_HOST_ALLOWLIST ?? "")
       .split(",").map((value) => value.trim()).filter((value) => value.length > 0),
     acquireActiveRuntime: async (workspaceId) => {

backend/src/workspaces/bindings.ts

@@ -59,12 +59,12 @@ function safeSecretFilePath(path: string, secretRoots: readonly string[]): strin
 
 function requireSupportedDescriptor(workspace: unknown): void {
   if (typeof workspace !== "object" || workspace === null) {
-    throw new Error("Workspace bindings support only workspace schema version 3");
+    throw new Error("Workspace bindings support only workspace schema version 4");
   }
   const metadata = Reflect.get(workspace, "workspace");
   if (typeof metadata !== "object" || metadata === null
-    || Reflect.get(metadata, "schema_version") !== 3) {
-    throw new Error("Workspace bindings support only workspace schema version 3");
+    || Reflect.get(metadata, "schema_version") !== 4) {
+    throw new Error("Workspace bindings support only workspace schema version 4");
   }
 }
 
@@ -155,7 +155,7 @@ export function resolveEvidenceBinding(
   return { values, missing };
 }
 
-/** Resolve the complete schema-v3 runtime binding set. */
+/** Resolve the complete schema-v4 runtime binding set. */
 export function resolveRuntimeBindings(
   workspace: WorkspaceDescriptor,
   env: NodeJS.ProcessEnv,

backend/src/workspaces/contracts.ts

@@ -137,12 +137,12 @@ function evidenceVariables(
 
 function requireSupportedDescriptor(workspace: unknown): void {
   if (typeof workspace !== "object" || workspace === null) {
-    throw new Error("Installation contract supports only workspace schema version 3");
+    throw new Error("Installation contract supports only workspace schema version 4");
   }
   const metadata = Reflect.get(workspace, "workspace");
   if (typeof metadata !== "object" || metadata === null
-    || Reflect.get(metadata, "schema_version") !== 3) {
-    throw new Error("Installation contract supports only workspace schema version 3");
+    || Reflect.get(metadata, "schema_version") !== 4) {
+    throw new Error("Installation contract supports only workspace schema version 4");
   }
 }
 

backend/src/workspaces/diagnostics.ts

@@ -406,12 +406,12 @@ function numericBinding(binding: Record<string, string>, name: string): number |
 
 function requireSupportedDescriptor(workspace: unknown): void {
   if (typeof workspace !== "object" || workspace === null) {
-    throw new Error("Workspace diagnoser supports only workspace schema version 3");
+    throw new Error("Workspace diagnoser supports only workspace schema version 4");
   }
   const metadata = Reflect.get(workspace, "workspace");
   if (typeof metadata !== "object" || metadata === null
-    || Reflect.get(metadata, "schema_version") !== 3) {
-    throw new Error("Workspace diagnoser supports only workspace schema version 3");
+    || Reflect.get(metadata, "schema_version") !== 4) {
+    throw new Error("Workspace diagnoser supports only workspace schema version 4");
   }
 }
 
@@ -506,11 +506,15 @@ async function diagnoseValidatedWorkspace(
   try {
     const vector = await withTimeout(timeoutMs, (signal) => adapters.inspectQdrant({
       baseUrl: semanticRuntime.internalQdrantUrl,
-      collection: descriptor.semantic_index.vector_store.collection,
+      collection: descriptor.workspace.id,
       timeoutMs,
       signal,
     }));
-    const expected = descriptor.semantic_index.vector_store;
+    const expected = {
+      collection: descriptor.workspace.id,
+      dimensions: semanticRuntime.internalEmbeddingDimensions,
+      distance: "cosine",
+    };
     if (vector.collection !== expected.collection
       || vector.dimensions !== expected.dimensions
       || vector.distance !== expected.distance) {
@@ -529,10 +533,8 @@ async function diagnoseValidatedWorkspace(
       timeoutMs,
       signal,
     }));
-    if (semanticRuntime.internalEmbeddingModel !== descriptor.semantic_index.embedding.model
-      || semanticRuntime.internalEmbeddingDimensions !== descriptor.semantic_index.embedding.dimensions
-      || !embedding.available
-      || embedding.dimensions !== descriptor.semantic_index.embedding.dimensions) {
+    if (!embedding.available
+      || embedding.dimensions !== semanticRuntime.internalEmbeddingDimensions) {
       diagnostics.push(diagnosticError("semantic_index_incompatible"));
       activatable = false;
     }

backend/src/workspaces/effective-config.ts

@@ -2,7 +2,7 @@ import { createHash } from "node:crypto";
 import { normalize } from "node:path";
 
 export interface CanonicalEffectiveConfig {
-  schemaVersion: 1;
+  schemaVersion: 2;
   dwh: CanonicalDwhConfig;
   vector: CanonicalVectorConfig;
   embedding: CanonicalEmbeddingConfig;
@@ -27,6 +27,7 @@ export interface CanonicalVectorConfig {
 }
 
 export interface CanonicalEmbeddingConfig {
+  id: string;
   model: string;
   dimensions: number;
 }
@@ -137,8 +138,10 @@ function buildEmbeddingConfig(rendered: Record<string, unknown>): CanonicalEmbed
   if (!embeddings) {
     throw new TypeError("effective config is missing embedding resources");
   }
+  const model = requireString(embeddings, "model");
   return {
-    model: requireString(embeddings, "model"),
+    id: `ollama/${model}`,
+    model,
     dimensions: requireNumber(embeddings, "dimensions"),
   };
 }
@@ -166,7 +169,7 @@ export function buildCanonicalEffectiveConfig(renderedConfig: unknown): Canonica
     throw new TypeError("effective config requires a rendered configuration object");
   }
   return {
-    schemaVersion: 1,
+    schemaVersion: 2,
     dwh: buildDwhConfig(rendered),
     vector: buildVectorConfig(rendered),
     embedding: buildEmbeddingConfig(rendered),

backend/src/workspaces/preprocessing-service.ts

@@ -77,6 +77,7 @@ export interface WorkspacePreprocessingServiceDeps {
     { ok: true } | { ok: false; code: "workspace_not_activatable" | "semantic_index_incompatible" }
   >;
   httpPrivateHostAllowlist?: readonly string[];
+  embeddingDimensions?: number;
 }
 
 interface RunScope {
@@ -118,7 +119,7 @@ export class WorkspacePreprocessingService {
 
   async vectorInspect(options: { workspaceId: string }): Promise<WorkspaceOperationResult> {
     const runtime = await this.deps.acquireActiveRuntime(options.workspaceId);
-    const collection = runtime.workspace.semantic_index.vector_store.collection;
+    const collection = runtime.workspace.workspace.id;
     const res = await fetch(`${runtime.configLease.semanticQdrantUrl}/collections/${encodeURIComponent(collection)}`, { method: "GET" });
     if (!res.ok) return baseResult(runtime, "vector inspect", "failed", "semantic_index_incompatible", { warnings: ["collection unavailable"] });
     const body = await res.json() as any;
@@ -132,7 +133,7 @@ export class WorkspacePreprocessingService {
 
   async vectorRebuild(options: { workspaceId: string; collection?: string; confirm?: string; destroy?: boolean }): Promise<WorkspaceOperationResult> {
     const runtime = await this.deps.acquireActiveRuntime(options.workspaceId);
-    const collection = runtime.workspace.semantic_index.vector_store.collection;
+    const collection = runtime.workspace.workspace.id;
     if (options.collection !== collection || options.confirm !== collection || options.destroy !== true) {
       return baseResult(runtime, "vector rebuild", "failed", "semantic_index_incompatible", { warnings: ["rebuild requires exact confirmation and --destroy"] });
     }
@@ -143,8 +144,8 @@ export class WorkspacePreprocessingService {
     const recreated = await reconcileCollection({
       baseUrl: runtime.configLease.semanticQdrantUrl,
       collection,
-      dimensions: runtime.workspace.semantic_index.vector_store.dimensions,
-      distance: runtime.workspace.semantic_index.vector_store.distance,
+      dimensions: this.deps.embeddingDimensions ?? 1024,
+      distance: "cosine",
       mode: "self_heal",
     });
     if (!recreated.ok) return baseResult(runtime, "vector rebuild", "failed", "semantic_index_incompatible", { warnings: ["collection recreate failed"] });
@@ -400,6 +401,8 @@ export class WorkspacePreprocessingService {
       catalogBlob: runtime.catalogBlob,
       configDigest: runtime.configLease.configDigest,
       bindingDigest: runtime.configLease.bindingDigest,
+      embeddingId: runtime.configLease.effectiveConfig.embedding.id,
+      embeddingDimensions: runtime.configLease.effectiveConfig.embedding.dimensions,
     });
     return { runtime, state, job };
   }

backend/src/workspaces/preprocessing-state.ts

@@ -44,11 +44,13 @@ export interface BeginPreprocessingJobOptions {
   catalogBlob: string;
   configDigest: string;
   bindingDigest: string;
+  embeddingId: string;
+  embeddingDimensions: number;
   runId?: string;
 }
 
 export interface PreprocessingJobState {
-  schemaVersion: 1;
+  schemaVersion: 2;
   runId: string;
   operation: string;
   workspaceId: string;
@@ -57,6 +59,8 @@ export interface PreprocessingJobState {
   catalogBlob: string;
   configDigest: string;
   bindingDigest: string;
+  embeddingId: string;
+  embeddingDimensions: number;
   completedStages: string[];
   childRuns: Record<string, string>;
   status: "active" | "succeeded" | "blocked" | "failed";
@@ -146,7 +150,7 @@ function decodeJob(value: unknown): PreprocessingJobState {
   }
   const record = value as Record<string, unknown>;
   if (
-    record.schemaVersion !== 1
+    record.schemaVersion !== 2
     || typeof record.runId !== "string"
     || typeof record.operation !== "string"
     || typeof record.workspaceId !== "string"
@@ -155,6 +159,8 @@ function decodeJob(value: unknown): PreprocessingJobState {
     || typeof record.catalogBlob !== "string"
     || typeof record.configDigest !== "string"
     || typeof record.bindingDigest !== "string"
+    || typeof record.embeddingId !== "string"
+    || typeof record.embeddingDimensions !== "number"
     || !Array.isArray(record.completedStages)
     || typeof record.childRuns !== "object" || record.childRuns === null || Array.isArray(record.childRuns)
     || !["active", "succeeded", "blocked", "failed"].includes(String(record.status))
@@ -275,6 +281,8 @@ export class PreprocessingStateStore {
         || existing.catalogBlob !== options.catalogBlob
         || existing.configDigest !== options.configDigest
         || existing.bindingDigest !== options.bindingDigest
+        || existing.embeddingId !== options.embeddingId
+        || existing.embeddingDimensions !== options.embeddingDimensions
       ) {
         throw new PreprocessingStateError(
           "preprocessing_resume_mismatch",
@@ -295,7 +303,7 @@ export class PreprocessingStateStore {
       }
     }
     const job: PreprocessingJobState = {
-      schemaVersion: 1,
+      schemaVersion: 2,
       runId,
       operation: options.operation,
       workspaceId: this.options.workspaceId,
@@ -304,6 +312,8 @@ export class PreprocessingStateStore {
       catalogBlob: options.catalogBlob,
       configDigest: options.configDigest,
       bindingDigest: options.bindingDigest,
+      embeddingId: options.embeddingId,
+      embeddingDimensions: options.embeddingDimensions,
       completedStages: [],
       childRuns: {},
       status: "active",

backend/src/workspaces/registry.ts

@@ -560,7 +560,7 @@ export class WorkspaceRegistry {
             });
           }
         }
-        const collection = workspace.semantic_index.vector_store.collection;
+        const collection = workspace.workspace.id;
         const owner = collectionOwners.get(collection);
         if (owner !== undefined) {
           throw new Error(`duplicate qdrant collection ownership: ${collection} (${owner}, ${id})`);

backend/src/workspaces/runtime-renderer.ts

@@ -34,6 +34,7 @@ export interface RuntimeInstallationOverlay {
 export interface SemanticRuntimeConfig {
   internalQdrantUrl: string;
   internalEmbeddingUrl: string;
+  internalEmbeddingId?: string;
   internalEmbeddingModel: string;
   internalEmbeddingDimensions: number;
 }
@@ -41,6 +42,7 @@ export interface SemanticRuntimeConfig {
 export const DEFAULT_SEMANTIC_RUNTIME: SemanticRuntimeConfig = {
   internalQdrantUrl: "http://qdrant:6333",
   internalEmbeddingUrl: "http://embedding:11434",
+  internalEmbeddingId: "ollama/qwen3-embedding:0.6b",
   internalEmbeddingModel: "qwen3-embedding:0.6b",
   internalEmbeddingDimensions: 1024,
 };
@@ -202,16 +204,16 @@ function placeholderConnection(identity: { database: string; schema: string }):
 
 function requireSupportedDescriptor(workspace: unknown): void {
   if (typeof workspace !== "object" || workspace === null) {
-    throw new Error("Runtime renderer supports only workspace schema version 3");
+    throw new Error("Runtime renderer supports only workspace schema version 4");
   }
   const metadata = Reflect.get(workspace, "workspace");
   if (typeof metadata !== "object" || metadata === null
-    || Reflect.get(metadata, "schema_version") !== 3) {
-    throw new Error("Runtime renderer supports only workspace schema version 3");
+    || Reflect.get(metadata, "schema_version") !== 4) {
+    throw new Error("Runtime renderer supports only workspace schema version 4");
   }
 }
 
-/** Render the schema-v3 compatibility fields consumed by the current Python harness. */
+/** Render the schema-v4 compatibility fields consumed by the current Python harness. */
 export function renderRuntimeConfig(
   workspace: WorkspaceDescriptor,
   bindings: RuntimeBindings,
@@ -263,12 +265,24 @@ export function renderRuntimeConfig(
     ...(installation.profile === undefined ? {} : { profile: installation.profile }),
     language: descriptor.workspace.language,
     database,
-    semantic_index: descriptor.semantic_index,
+    semantic_index: {
+      vector_store: {
+        engine: "qdrant",
+        collection: descriptor.workspace.id,
+        dimensions: semanticRuntime.internalEmbeddingDimensions,
+        distance: "cosine",
+      },
+      embedding: {
+        provider: "ollama_internal",
+        model: semanticRuntime.internalEmbeddingModel,
+        dimensions: semanticRuntime.internalEmbeddingDimensions,
+      },
+    },
     resources: {
       vector: {
         engine: "qdrant",
         base_url: semanticRuntime.internalQdrantUrl,
-        collection: descriptor.semantic_index.vector_store.collection,
+        collection: descriptor.workspace.id,
       },
       embeddings: {
         provider: "ollama_internal",

backend/src/workspaces/schema.ts

@@ -35,7 +35,7 @@ export interface CanonicalDiagnostics {
 }
 
 interface WorkspaceMetadata {
-  schema_version: 3;
+  schema_version: 4;
   id: string;
   name: string;
   description?: string;
@@ -51,31 +51,12 @@ interface WorkspaceDwh {
   supported_transports: DwhTransport[];
 }
 
-interface WorkspaceBase<TVectorStore> {
+interface WorkspaceBase {
   workspace: WorkspaceMetadata;
   dwh: WorkspaceDwh;
-  semantic_index: {
-    vector_store: TVectorStore;
-    embedding: {
-      provider: "ollama_internal";
-      model: "qwen3-embedding:0.6b";
-      dimensions: 1024;
-    };
-  };
-  llm_policy: {
-    default?: `${string}/${string}`;
-    allowed: `${string}/${string}`[];
-  };
   diagnostics?: Pick<CanonicalDiagnostics, "dwh_rest">;
 }
 
-interface QdrantVectorStore {
-  engine: "qdrant";
-  collection: string;
-  dimensions: 1024;
-  distance: "cosine";
-}
-
 export interface EvidencePolicy {
   max_chunk_chars: number;
   retain_published_generations: number;
@@ -120,12 +101,12 @@ export interface WorkspaceEvidence {
   policy: EvidencePolicy;
 }
 
-export interface WorkspaceV3 extends WorkspaceBase<QdrantVectorStore> {
+export interface WorkspaceV4 extends WorkspaceBase {
   evidence?: WorkspaceEvidence;
 }
 
-export type CanonicalWorkspace = WorkspaceV3;
-export type WorkspaceDescriptor = WorkspaceV3;
+export type CanonicalWorkspace = WorkspaceV4;
+export type WorkspaceDescriptor = WorkspaceV4;
 
 const workspaceId = z.string().regex(/^[a-z][a-z0-9-]{2,62}$/, {
   message: "workspace id must match ^[a-z][a-z0-9-]{2,62}$",
@@ -135,9 +116,6 @@ const identifier = z.string().regex(/^[A-Za-z_][A-Za-z0-9_]*$/, {
 });
 const port = z.number().int().min(1).max(65_535);
 const timeoutMs = z.number().int().positive();
-const modelReference = z.string().regex(/^[^/\s]+\/[^/\s]+$/, {
-  message: "model must use provider/model syntax",
-});
 
 function isOriginRelativeDiagnosticPath(value: string): boolean {
   return /^\/(?!\/)[^\\\u0000-\u001F\u007F?#]*$/.test(value) && !/%5c/i.test(value);
@@ -166,21 +144,6 @@ const dwhSchema = z.object({
   timeout_ms: timeoutMs.optional(),
   supported_transports: z.array(z.enum(DWH_TRANSPORTS)).min(1),
 }).strict();
-const internalEmbeddingSchema = z.object({
-  provider: z.literal("ollama_internal"),
-  model: z.literal("qwen3-embedding:0.6b"),
-  dimensions: z.literal(1024),
-}).strict();
-const qdrantVectorStoreSchema = z.object({
-  engine: z.literal("qdrant"),
-  collection: workspaceId,
-  dimensions: z.literal(1024),
-  distance: z.literal("cosine"),
-}).strict();
-const llmPolicySchema = z.object({
-  default: modelReference.optional(),
-  allowed: z.array(modelReference).min(1),
-}).strict();
 
 const positiveSafeInteger = z.number().int().safe().positive();
 const nonnegativeSafeInteger = z.number().int().safe().nonnegative();
@@ -366,7 +329,6 @@ function unique<T>(values: readonly T[], context: z.RefinementCtx, path: Propert
 
 function workspaceInvariants(workspace: any, context: z.RefinementCtx): void {
   unique(workspace.dwh.supported_transports, context, ["dwh", "supported_transports"]);
-  unique(workspace.llm_policy.allowed, context, ["llm_policy", "allowed"]);
 
   if (workspace.evidence?.source.type === "filesystem") {
     const expected = `${workspace.workspace.id}/evidence`;
@@ -379,20 +341,6 @@ function workspaceInvariants(workspace: any, context: z.RefinementCtx): void {
     }
   }
 
-  if (workspace.semantic_index.vector_store.dimensions !== workspace.semantic_index.embedding.dimensions) {
-    context.addIssue({
-      code: "custom",
-      path: ["semantic_index", "embedding", "dimensions"],
-      message: "embedding dimensions must match vector store dimensions",
-    });
-  }
-  if (workspace.llm_policy.default && !workspace.llm_policy.allowed.includes(workspace.llm_policy.default)) {
-    context.addIssue({
-      code: "custom",
-      path: ["llm_policy", "default"],
-      message: "LLM default must be included in the allowlist",
-    });
-  }
   if (workspace.diagnostics?.dwh_rest && !workspace.dwh.supported_transports.includes("rest_api")) {
     context.addIssue({
       code: "custom",
@@ -402,23 +350,18 @@ function workspaceInvariants(workspace: any, context: z.RefinementCtx): void {
   }
 }
 
-const WorkspaceV3Schema = z.object({
+const WorkspaceV4Schema = z.object({
   dwh: dwhSchema,
-  llm_policy: llmPolicySchema,
   evidence: workspaceEvidenceSchema.optional(),
   diagnostics: z.object({
     dwh_rest: dwhRestDiagnostic.optional(),
   }).strict().optional(),
   workspace: z.object({
-    schema_version: z.literal(3), id: workspaceId, name: z.string().trim().min(1),
+    schema_version: z.literal(4), id: workspaceId, name: z.string().trim().min(1),
     description: z.string().trim().min(1).optional(), language: z.enum(["en", "it"]),
   }).strict(),
-  semantic_index: z.object({
-    vector_store: qdrantVectorStoreSchema,
-    embedding: internalEmbeddingSchema,
-  }).strict(),
 }).strict().superRefine(workspaceInvariants);
-const WorkspaceDescriptorSchema = WorkspaceV3Schema;
+const WorkspaceDescriptorSchema = WorkspaceV4Schema;
 
 export function parseWorkspaceYaml(source: string): WorkspaceDescriptor {
   const documents = parseAllDocuments(source, { uniqueKeys: true });
@@ -431,6 +374,25 @@ export function parseWorkspaceYaml(source: string): WorkspaceDescriptor {
   return validateWorkspaceDescriptor(document.toJSON());
 }
 
+/** Deterministically removes the two installation-owned v3 blocks without altering workspace data. */
+export function migrateWorkspaceV3Yaml(source: string): string {
+  const documents = parseAllDocuments(source, { uniqueKeys: true });
+  if (documents.length !== 1) throw new Error("Workspace YAML must contain exactly one document");
+  const document = documents[0];
+  if (document.errors.length > 0 || document.warnings.length > 0) {
+    throw new Error("Invalid workspace YAML");
+  }
+  const value = document.toJSON() as Record<string, unknown>;
+  const metadata = value.workspace as Record<string, unknown> | undefined;
+  if (!metadata || metadata.schema_version !== 3) {
+    throw new Error("Workspace migration requires schema version 3");
+  }
+  metadata.schema_version = 4;
+  delete value.semantic_index;
+  delete value.llm_policy;
+  return serializeWorkspaceYaml(validateWorkspaceDescriptor(value));
+}
+
 export function validateWorkspaceDescriptor(workspace: unknown): WorkspaceDescriptor {
   return WorkspaceDescriptorSchema.parse(workspace) as WorkspaceDescriptor;
 }
@@ -439,11 +401,11 @@ export function isCanonicalWorkspace(workspace: unknown): workspace is Canonical
   return WorkspaceDescriptorSchema.safeParse(workspace).success;
 }
 
-export function isOperationalWorkspace(workspace: unknown): workspace is WorkspaceV3 {
+export function isOperationalWorkspace(workspace: unknown): workspace is WorkspaceV4 {
   return WorkspaceDescriptorSchema.safeParse(workspace).success;
 }
 
-export function validateOperationalWorkspace(workspace: unknown): WorkspaceV3 {
+export function validateOperationalWorkspace(workspace: unknown): WorkspaceV4 {
   return validateWorkspaceDescriptor(workspace);
 }
 

backend/src/workspaces/types.ts

@@ -19,4 +19,4 @@ export type WorkspaceErrorCode =
   | "workspace_stale" | "git_unavailable" | "git_auth_failed" | "git_non_fast_forward"
   | "connector_unavailable" | "semantic_index_incompatible";
 
-export type { WorkspaceV3 } from "./schema.js";
+export type { WorkspaceV4 } from "./schema.js";

backend/test/auth-pi-management-local.test.ts

@@ -5,14 +5,12 @@ import { createLocalAuthFixture } from "./auth-test-fixtures.js";
 function fakeService(): PiManagementService {
   return {
     status: vi.fn(async () => ({ ready: true })),
-    options: vi.fn(async () => ({ providers: [], models: [], reasoning: [], checkedAt: "2026-08-17T00:00:00.000Z" })),
-    configure: vi.fn(async (value) => ({ ...value, updatedAt: "2026-08-17T00:00:00.000Z" })),
     test: vi.fn(async () => ({ ready: true, checkedAt: "2026-08-17T00:00:00.000Z" })),
     logs: vi.fn(async () => ({ lines: [] })),
   };
 }
 
-test("a local HTTPS cookie session authorizes Pi writes through an untrusted internal HTTP hop", async () => {
+test("a local HTTPS cookie session authorizes the Pi smoke check through an untrusted internal HTTP hop", async () => {
   const service = fakeService();
   const fixture = await createLocalAuthFixture(
     { piManagement: service },
@@ -25,31 +23,21 @@ test("a local HTTPS cookie session authorizes Pi writes through an untrusted int
     expect(fixture.publicUrl).toBe("HTTPS://thothii.example.test");
 
     const proxyHeaders = fixture.sessionHeaders({ host: "127.0.0.1:8080" });
-    const configured = await fixture.app.inject({
-      method: "PUT",
-      url: "/pi-management/config",
-      headers: proxyHeaders,
-      payload: { provider: "zai", model: "glm-5.2", reasoning: "high" },
-    });
     const smoke = await fixture.app.inject({
       method: "POST",
       url: "/pi-management/test",
       headers: proxyHeaders,
     });
 
-    expect(configured.statusCode).toBe(200);
     expect(smoke.statusCode).toBe(200);
-    expect(service.configure).toHaveBeenCalledTimes(1);
     expect(service.test).toHaveBeenCalledTimes(1);
 
     fixture.resetDownstreamHits();
-    vi.mocked(service.configure).mockClear();
     vi.mocked(service.test).mockClear();
     const wrongOrigin = await fixture.app.inject({
-      method: "PUT",
-      url: "/pi-management/config",
+      method: "POST",
+      url: "/pi-management/test",
       headers: fixture.sessionHeaders({ host: "127.0.0.1:8080", origin: "https://evil.example" }),
-      payload: { provider: "zai", model: "glm-5.2", reasoning: "high" },
     });
     const wrongCsrf = await fixture.app.inject({
       method: "POST",
@@ -62,7 +50,6 @@ test("a local HTTPS cookie session authorizes Pi writes through an untrusted int
       expect(response.json()).toEqual({ code: "csrf_failed", error: "Request origin validation failed" });
     }
     expect(fixture.downstreamHits()).toBe(0);
-    expect(service.configure).not.toHaveBeenCalled();
     expect(service.test).not.toHaveBeenCalled();
   } finally {
     await fixture.close();

backend/test/catalog-databases-routes.test.ts

@@ -19,16 +19,11 @@ afterEach(() => {
 });
 
 const workspace: WorkspaceDescriptor = {
-  workspace: { schema_version: 3, id: "psd-clinical", name: "Policlinico San Donato", language: "it" },
+  workspace: { schema_version: 4, id: "psd-clinical", name: "Policlinico San Donato", language: "it" },
   dwh: {
     engine: "postgres", database: "warehouse", schema: "datawarehouse", port: 5432,
     supported_transports: ["postgres_direct", "rest_api"],
   },
-  semantic_index: {
-    vector_store: { engine: "qdrant", collection: "psd", dimensions: 1024, distance: "cosine" },
-    embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-  },
-  llm_policy: { allowed: ["zai/glm-5.2"] },
   diagnostics: { dwh_rest: { method: "GET", path: "/health", auth: "bearer", response: { database: "database", schema: "schema" } } },
 };
 const revision: WorkspaceRevision = { id: "psd-clinical", commit: "a".repeat(40), blob: "b".repeat(40), snapshotPath: "/tmp/psd.yaml" };

backend/test/catalog-description-generation-routes.test.ts

@@ -24,7 +24,7 @@ import type { WorkspaceDescriptor } from "../src/workspaces/schema.js";
 
 const workspace: WorkspaceDescriptor = {
   workspace: {
-    schema_version: 3,
+    schema_version: 4,
     id: "psd-clinical",
     name: "Policlinico San Donato",
     language: "it",
@@ -36,11 +36,6 @@ const workspace: WorkspaceDescriptor = {
     port: 5432,
     supported_transports: ["postgres_direct"],
   },
-  semantic_index: {
-    vector_store: { engine: "qdrant", collection: "psd", dimensions: 1024, distance: "cosine" },
-    embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-  },
-  llm_policy: { allowed: ["zai/glm-5.2"] },
 };
 const revision: WorkspaceRevision = {
   id: "psd-clinical",
@@ -49,7 +44,7 @@ const revision: WorkspaceRevision = {
   snapshotPath: "/tmp/psd.yaml",
 };
 const configuredModel: ResolvedMetadataGenerationModel = {
-  id: "openai-mini",
+  id: "openai/gpt-4.1-mini",
   provider: "openai",
   model: "gpt-4.1-mini",
   apiKeyEnv: "OPENAI_API_KEY",
@@ -705,7 +700,7 @@ test("generates one selected Catalog Column from a single JSON code fence", asyn
     expect(completionRequest.messages[0]?.content).toContain('{"results":[');
     expect(completionRequest.messages[1]?.content).toContain(`"targetId":"${column.id}"`);
     expect(completionRequest.messages[1]?.content).not.toMatch(/source rows|samples|example values/i);
-    expect(start.body).not.toMatch(/test-provider-secret|gpt-4\.1|openai\/gpt|Catalog metadata/);
+    expect(start.body).not.toMatch(/test-provider-secret|Catalog metadata/);
 
     resolveCompletion(`\`\`\`json\n${JSON.stringify({
       results: [{
@@ -2909,7 +2904,7 @@ test("validates selected targets and resolves every requested target before laun
     const unknownModel = await app.inject({
       method: "POST",
       url: `/catalog/databases/${database.id}/description-generation-runs`,
-      payload: { modelId: "unknown-model", scope: "selected_columns", targetIds: [column.id] },
+      payload: { modelId: "openai/unknown-model", scope: "selected_columns", targetIds: [column.id] },
     });
     expect(unknownModel.statusCode).toBe(409);
     expect(unknownModel.json().code).toBe("metadata_generation_model_unavailable");

backend/test/catalog-description-generation.integration.test.ts

@@ -14,6 +14,7 @@ import { up as upDescriptionGeneration } from "../src/catalog/migrations/005_des
 import { up as upSensitiveDataFlag } from "../src/catalog/migrations/006_sensitive_data_flag.js";
 import { up as upSensitiveSuggestionRuns } from "../src/catalog/migrations/007_sensitive_data_suggestion_runs.js";
 import { up as upAiTokenUsage } from "../src/catalog/migrations/009_ai_token_usage.js";
+import { up as upCanonicalModelIds } from "../src/catalog/migrations/010_canonical_model_ids.js";
 import { KyselyCatalogRepository, type CatalogDatabase } from "../src/catalog/repository.js";
 import { loadConfig } from "../src/config.js";
 import type { WorkspaceRegistry } from "../src/workspaces/registry.js";
@@ -50,6 +51,7 @@ test.skipIf(!dockerAvailable)("Fastify persists Description Generation success a
     await upDescriptionGeneration(db);
     await upSensitiveSuggestionRuns(db);
     await upAiTokenUsage(db);
+    await upCanonicalModelIds(db);
     const repository = new KyselyCatalogRepository(db);
     const database = await repository.create({
       workspaceId: "psd-clinical",
@@ -158,9 +160,9 @@ test.skipIf(!dockerAvailable)("Fastify persists Description Generation success a
       }),
     };
     const models: MetadataGenerationModels = {
-      catalog: () => ({ models: [{ id: "openai-mini", label: "OpenAI Mini" }], default: "openai-mini" }),
+      catalog: () => ({ models: [{ id: "openai/gpt-4.1-mini", label: "OpenAI Mini" }], default: "openai/gpt-4.1-mini" }),
       resolve: () => ({
-        id: "openai-mini",
+        id: "openai/gpt-4.1-mini",
         provider: "openai",
         model: "gpt-4.1-mini",
         apiKeyEnv: "OPENAI_API_KEY",
@@ -205,12 +207,12 @@ test.skipIf(!dockerAvailable)("Fastify persists Description Generation success a
       method: "POST",
       url: `/catalog/databases/${database.id}/description-generation-runs`,
       payload: {
-        modelId: "openai-mini",
+        modelId: "openai/gpt-4.1-mini",
         scope: "selected_columns",
         targetIds: [status.id, birthDate.id],
       },
     });
-    expect(successfulStart.statusCode).toBe(202);
+    expect(successfulStart.statusCode, successfulStart.body).toBe(202);
     expect(await terminalRun(app, successfulStart.json().id)).toMatchObject({
       status: "completed",
       total: 2,
@@ -233,7 +235,7 @@ test.skipIf(!dockerAvailable)("Fastify persists Description Generation success a
     const tableStart = await app.inject({
       method: "POST",
       url: `/catalog/databases/${database.id}/description-generation-runs`,
-      payload: { modelId: "openai-mini", scope: "selected_tables", targetIds: [table.id] },
+      payload: { modelId: "openai/gpt-4.1-mini", scope: "selected_tables", targetIds: [table.id] },
     });
     expect(tableStart.statusCode).toBe(202);
     expect(await terminalRun(app, tableStart.json().id)).toMatchObject({
@@ -253,7 +255,7 @@ test.skipIf(!dockerAvailable)("Fastify persists Description Generation success a
     const failedStart = await app.inject({
       method: "POST",
       url: `/catalog/databases/${database.id}/description-generation-runs`,
-      payload: { modelId: "openai-mini", scope: "selected_columns", targetIds: [status.id] },
+      payload: { modelId: "openai/gpt-4.1-mini", scope: "selected_columns", targetIds: [status.id] },
     });
     expect(failedStart.statusCode).toBe(202);
     const failedRun = await terminalRun(app, failedStart.json().id);
@@ -283,7 +285,7 @@ test.skipIf(!dockerAvailable)("Fastify persists Description Generation success a
     const allStart = await app.inject({
       method: "POST",
       url: `/catalog/databases/${database.id}/description-generation-runs`,
-      payload: { modelId: "openai-mini", scope: "all" },
+      payload: { modelId: "openai/gpt-4.1-mini", scope: "all" },
     });
     expect(allStart.statusCode).toBe(202);
     const allRun = await terminalRun(app, allStart.json().id);
@@ -327,7 +329,7 @@ test.skipIf(!dockerAvailable)("Fastify persists Description Generation success a
     const missingStart = await app.inject({
       method: "POST",
       url: `/catalog/databases/${database.id}/description-generation-runs`,
-      payload: { modelId: "openai-mini", scope: "missing" },
+      payload: { modelId: "openai/gpt-4.1-mini", scope: "missing" },
     });
     expect(missingStart.statusCode).toBe(202);
     expect(await terminalRun(app, missingStart.json().id)).toMatchObject({

backend/test/catalog-repository.integration.test.ts

@@ -14,6 +14,7 @@ import { up as upSensitiveDataFlag } from "../src/catalog/migrations/006_sensiti
 import { up as upSensitiveSuggestionRuns } from "../src/catalog/migrations/007_sensitive_data_suggestion_runs.js";
 import { up as upLogicalRelationships } from "../src/catalog/migrations/008_catalog_logical_relationships.js";
 import { up as upAiTokenUsage } from "../src/catalog/migrations/009_ai_token_usage.js";
+import { up as upCanonicalModelIds } from "../src/catalog/migrations/010_canonical_model_ids.js";
 
 const dockerAvailable = spawnSync("docker", ["info"], { stdio: "ignore" }).status === 0;
 
@@ -32,6 +33,7 @@ test.skipIf(!dockerAvailable)("PostgreSQL migration enforces one database per wo
     await upDescriptionGeneration(db);
     await upSensitiveSuggestionRuns(db);
     await upAiTokenUsage(db);
+    await upCanonicalModelIds(db);
     await sql`CREATE ROLE thothii_catalog_runtime`.execute(db);
     await upRuntimeSequencePrivileges(db);
     const sequencePrivilege = await sql<{ allowed: boolean }>`
@@ -391,6 +393,7 @@ test.skipIf(!dockerAvailable)("PostgreSQL repository persists description and se
     await upDescriptionGeneration(db);
     await upSensitiveSuggestionRuns(db);
     await upAiTokenUsage(db);
+    await upCanonicalModelIds(db);
     const repository = new KyselyCatalogRepository(db);
     const firstDatabase = await repository.create({
       workspaceId: "generation-one",
@@ -428,14 +431,14 @@ test.skipIf(!dockerAvailable)("PostgreSQL repository persists description and se
     const run = await repository.createDescriptionGenerationRun(
       firstDatabase.id,
       "selected_columns",
-      "openai-mini",
+      "openai/gpt-4.1-mini",
       "it",
       1,
     );
     expect(run).toMatchObject({
       databaseId: firstDatabase.id,
       scope: "selected_columns",
-      modelId: "openai-mini",
+      modelId: "openai/gpt-4.1-mini",
       language: "it",
       status: "queued",
       total: 1,
@@ -450,7 +453,7 @@ test.skipIf(!dockerAvailable)("PostgreSQL repository persists description and se
     await expect(repository.createDescriptionGenerationRun(
       secondDatabase.id,
       "selected_columns",
-      "openai-mini",
+      "openai/gpt-4.1-mini",
       "en",
       1,
     )).rejects.toThrow("A description generation run is already active");
@@ -461,7 +464,7 @@ test.skipIf(!dockerAvailable)("PostgreSQL repository persists description and se
     await expect(repository.createDescriptionGenerationRun(
       secondDatabase.id,
       "selected_columns",
-      "openai-mini",
+      "openai/gpt-4.1-mini",
       "en",
       1,
     )).rejects.toThrow("A description generation run is already active");
@@ -505,7 +508,7 @@ test.skipIf(!dockerAvailable)("PostgreSQL repository persists description and se
     const next = await repository.createDescriptionGenerationRun(
       secondDatabase.id,
       "missing",
-      "openai-mini",
+      "openai/gpt-4.1-mini",
       "en",
       1,
     );
@@ -533,7 +536,7 @@ test.skipIf(!dockerAvailable)("PostgreSQL repository persists description and se
     const allRun = await repository.createDescriptionGenerationRun(
       firstDatabase.id,
       "all",
-      "openai-mini",
+      "openai/gpt-4.1-mini",
       "it",
       2,
     );
@@ -562,7 +565,7 @@ test.skipIf(!dockerAvailable)("PostgreSQL repository persists description and se
     const suggestionRun = await repository.createSensitiveDataSuggestionRun(
       firstDatabase.id,
       "selected_columns",
-      "openai-mini",
+      "openai/gpt-4.1-mini",
     );
     expect(suggestionRun).toMatchObject({
       databaseId: firstDatabase.id,
@@ -604,7 +607,7 @@ test.skipIf(!dockerAvailable)("PostgreSQL repository persists description and se
     const interruptedSuggestionRun = await repository.createSensitiveDataSuggestionRun(
       secondDatabase.id,
       "all",
-      "openai-mini",
+      "openai/gpt-4.1-mini",
     );
     expect(await repository.interruptActiveSensitiveDataSuggestionRuns(
       "Sensitive-field suggestion generation was interrupted by backend restart.",

backend/test/catalog-schema-routes.test.ts

@@ -16,13 +16,8 @@ const roots: string[] = [];
 afterEach(() => { for (const root of roots.splice(0)) rmSync(root, { recursive: true, force: true }); });
 
 const workspace: WorkspaceDescriptor = {
-  workspace: { schema_version: 3, id: "psd-clinical", name: "Policlinico San Donato", language: "it" },
+  workspace: { schema_version: 4, id: "psd-clinical", name: "Policlinico San Donato", language: "it" },
   dwh: { engine: "postgres", database: "warehouse", schema: "datawarehouse", port: 5432, supported_transports: ["postgres_direct"] },
-  semantic_index: {
-    vector_store: { engine: "qdrant", collection: "psd", dimensions: 1024, distance: "cosine" },
-    embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-  },
-  llm_policy: { allowed: ["zai/glm-5.2"] },
 };
 const revision: WorkspaceRevision = { id: "psd-clinical", commit: "a".repeat(40), blob: "b".repeat(40), snapshotPath: "/tmp/psd.yaml" };
 

backend/test/catalog-tables-routes.test.ts

@@ -13,16 +13,11 @@ const roots: string[] = [];
 afterEach(() => { for (const root of roots.splice(0)) rmSync(root, { recursive: true, force: true }); });
 
 const workspace: WorkspaceDescriptor = {
-  workspace: { schema_version: 3, id: "psd-clinical", name: "Policlinico San Donato", language: "it" },
+  workspace: { schema_version: 4, id: "psd-clinical", name: "Policlinico San Donato", language: "it" },
   dwh: {
     engine: "postgres", database: "warehouse", schema: "datawarehouse", port: 5432,
     supported_transports: ["postgres_direct", "rest_api"],
   },
-  semantic_index: {
-    vector_store: { engine: "qdrant", collection: "psd", dimensions: 1024, distance: "cosine" },
-    embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-  },
-  llm_policy: { allowed: ["zai/glm-5.2"] },
   diagnostics: { dwh_rest: { method: "GET", path: "/health", auth: "bearer", response: { database: "database", schema: "schema" } } },
 };
 const revision: WorkspaceRevision = {

backend/test/config.test.ts

@@ -71,6 +71,7 @@ test("loadConfig keeps local development defaults", () => {
     workspaceSecretRuntimeRoot: "/tmp/thothii-workspace-secrets",
     internalQdrantUrl: "http://qdrant:6333",
     internalEmbeddingUrl: "http://embedding:11434",
+    internalEmbeddingId: "ollama/qwen3-embedding:0.6b",
     internalEmbeddingModel: "qwen3-embedding:0.6b",
     internalEmbeddingDimensions: 1024,
     authMode: "none",
@@ -198,6 +199,22 @@ test("loadConfig accepts only the allowed internal semantic runtime hosts", () =
     .toThrow(/internal.*embedding|invalid/i);
 });
 
+test("loadConfig derives the embedding runtime model from its canonical catalog identity", () => {
+  expect(loadConfig({
+    THT_INTERNAL_EMBEDDING_ID: "ollama/nomic-embed-text",
+    THT_INTERNAL_EMBEDDING_MODEL: "nomic-embed-text",
+  })).toMatchObject({
+    internalEmbeddingId: "ollama/nomic-embed-text",
+    internalEmbeddingModel: "nomic-embed-text",
+  });
+  expect(() => loadConfig({
+    THT_INTERNAL_EMBEDDING_ID: "ollama/nomic-embed-text",
+    THT_INTERNAL_EMBEDDING_MODEL: "different-model",
+  })).toThrow("does not match its canonical identity");
+  expect(() => loadConfig({ THT_INTERNAL_EMBEDDING_ID: "not-canonical" }))
+    .toThrow("embedding identity configuration is invalid");
+});
+
 test("loadConfig enables the legacy workspace request only through explicit local mode", () => {
   expect(loadConfig({ THT_LEGACY_WORKSPACE_MODE: "local" }).legacyWorkspaceMode).toBe(true);
 

backend/test/effective-config.test.ts

@@ -11,6 +11,7 @@ import {
 const semanticRuntime = {
   internalQdrantUrl: "http://qdrant:6333",
   internalEmbeddingUrl: "http://embedding:11434",
+  internalEmbeddingId: "ollama/qwen3-embedding:0.6b",
   internalEmbeddingModel: "qwen3-embedding:0.6b",
   internalEmbeddingDimensions: 1024,
 };
@@ -102,11 +103,11 @@ function restRendered(): Record<string, unknown> {
 }
 
 const directCanonical =
-  `{"schemaVersion":1,"dwh":{` +
+  `{"schemaVersion":2,"dwh":{` +
   `"engine":"postgres","database":"postgres","schema":"datawarehouse",` +
   `"transport":"postgres_direct","host":"dwh.internal","port":5432,"user":"thoth_reader"},` +
   `"vector":{"collection":"psd-clinical","dimensions":1024,"distance":"cosine"},` +
-  `"embedding":{"model":"qwen3-embedding:0.6b","dimensions":1024},` +
+  `"embedding":{"id":"ollama/qwen3-embedding:0.6b","model":"qwen3-embedding:0.6b","dimensions":1024},` +
   `"roots":{"artifacts":"/data/sessions/psd-clinical/artifacts",` +
   `"indexes":"/data/sessions/psd-clinical/indexes"}}`;
 
@@ -192,6 +193,9 @@ test("DWH-affecting changes alter the effective config identity", () => {
   const changedCollection = { ...base, resources: { ...base.resources, vector: { ...(base.resources as Record<string, any>).vector, collection: "other" } } };
   expect(effectiveConfigIdentity("psd-clinical", changedCollection)).not.toBe(identityBefore);
 
+  const changedEmbeddingIdentity = { ...base, resources: { ...base.resources, embeddings: { ...(base.resources as Record<string, any>).embeddings, model: "other-embedding" } } };
+  expect(effectiveConfigIdentity("psd-clinical", changedEmbeddingIdentity)).not.toBe(identityBefore);
+
   const changedTransport = restRendered();
   expect(effectiveConfigIdentity("psd-clinical", changedTransport)).not.toBe(identityBefore);
 });

backend/test/metadata-generation-models.test.ts

@@ -1,15 +1,12 @@
 import { chmodSync, mkdtempSync, rmSync, writeFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
-import { afterEach, expect, test, vi } from "vitest";
-import { buildApp } from "../src/app.js";
-import { MemoryCatalogRepository } from "../src/catalog/memory-repository.js";
+import { afterEach, expect, test } from "vitest";
 import {
   loadMetadataGenerationModels,
   MetadataGenerationModelUnavailableError,
 } from "../src/catalog/metadata-generation-models.js";
-import { loadConfig } from "../src/config.js";
-import type { WorkspaceRegistry } from "../src/workspaces/registry.js";
+import { loadRuntimeModelCatalog, splitCanonicalModelId } from "../src/models/runtime-model-catalog.js";
 
 const roots: string[] = [];
 
@@ -17,260 +14,101 @@ afterEach(() => {
   for (const root of roots.splice(0)) rmSync(root, { recursive: true, force: true });
 });
 
-function metadataConfiguration(
-  metadataGeneration: string,
-  secrets = "OPENAI_API_KEY=raw-provider-secret\n",
-) {
-  const root = mkdtempSync(join(tmpdir(), "thothii-metadata-models-"));
+function runtimeCatalog(overrides: Record<string, unknown> = {}, secrets = "OPENAI_API_KEY=raw-provider-secret\n") {
+  const root = mkdtempSync(join(tmpdir(), "thothii-runtime-models-"));
   roots.push(root);
-  const installationFile = join(root, "thothii-installation.yaml");
+  const catalogFile = join(root, "catalog.json");
   const secretsFile = join(root, "thothii.secrets");
-  writeFileSync(installationFile, metadataGeneration, { mode: 0o600 });
-  writeFileSync(secretsFile, secrets, { mode: 0o600 });
-  chmodSync(installationFile, 0o600);
-  chmodSync(secretsFile, 0o600);
-  return { installationFile, secretsFile };
-}
-
-function appFor(installationFile: string, secretsFile: string) {
-  const config = loadConfig({
-    NODE_ENV: "test",
-    THT_HARNESS_DIR: "/missing",
-    THT_INSTALLATION_CONFIG_FILE: installationFile,
-    THT_SECRETS_FILE: secretsFile,
-    PI_PROVIDER: "unrelated-pi-provider",
-    PI_MODEL: "unrelated-pi-model",
-  });
-  return buildApp(config, {
-    thtRunner: {} as never,
-    workspaceRegistry: { list: vi.fn(async () => []) } as unknown as WorkspaceRegistry,
-    workspaceDiagnoser: vi.fn(),
-    catalogRepository: new MemoryCatalogRepository(),
-  });
-}
-
-test("exposes only safe metadata-generation choices and their configured default", async () => {
-  const { installationFile, secretsFile } = metadataConfiguration(`metadataGeneration:
-  default: openai-mini
-  models:
-    - id: openai-mini
-      label: OpenAI Mini
-      litellm:
-        provider: openai
-        model: gpt-4.1-mini
-        endpoint:
-          baseUrl: https://api.openai.example/v1
-          apiVersion: "2026-08-01"
-      apiKeyEnv: OPENAI_API_KEY
-`);
-  const app = appFor(installationFile, secretsFile);
-
-  const response = await app.inject({ method: "GET", url: "/catalog/metadata-generation/models" });
-
-  expect(response.statusCode).toBe(200);
-  expect(response.json()).toEqual({
-    models: [{ id: "openai-mini", label: "OpenAI Mini" }],
-    default: "openai-mini",
-  });
-  expect(response.body).not.toMatch(/openai\/gpt|gpt-4\.1|api\.openai|OPENAI_API_KEY|raw-provider-secret/);
-  await app.close();
-});
-
-test("rejects an unprotected installation descriptor", () => {
-  const { installationFile, secretsFile } = metadataConfiguration(`metadataGeneration:
-  default: openai-mini
-  models:
-    - id: openai-mini
-      label: OpenAI Mini
-      litellm: {provider: openai, model: gpt-4.1-mini}
-      apiKeyEnv: OPENAI_API_KEY
-`);
-  chmodSync(installationFile, 0o644);
-
-  expect(() => loadMetadataGenerationModels({ installationFile, secretsFile }))
-    .toThrow("metadata-generation installation is unavailable");
-});
-
-test("returns an empty safe catalog when no metadata-generation model is configured", async () => {
-  const { installationFile, secretsFile } = metadataConfiguration("profile: local\n");
-  const app = appFor(installationFile, secretsFile);
-
-  const response = await app.inject({ method: "GET", url: "/catalog/metadata-generation/models" });
-
-  expect(response.statusCode).toBe(200);
-  expect(response.json()).toEqual({ models: [], default: null });
-  await app.close();
-});
-
-test("resolves only a configured selection for the later generation boundary", () => {
-  const { installationFile, secretsFile } = metadataConfiguration(`metadataGeneration:
-  default: openai-mini
-  models:
-    - id: openai-mini
-      label: OpenAI Mini
-      litellm:
-        provider: openai
-        model: gpt-4.1-mini
-        endpoint: {baseUrl: https://api.openai.example/v1, apiVersion: "2026-08-01"}
-      apiKeyEnv: OPENAI_API_KEY
-`);
-  const models = loadMetadataGenerationModels({ installationFile, secretsFile });
-
-  expect(models.resolve("openai-mini")).toEqual({
-    id: "openai-mini",
-    provider: "openai",
-    model: "gpt-4.1-mini",
-    endpoint: { baseUrl: "https://api.openai.example/v1", apiVersion: "2026-08-01" },
-    apiKeyEnv: "OPENAI_API_KEY",
-    apiKey: "raw-provider-secret",
-  });
-  expect(() => models.resolve("unknown-model")).toThrow(MetadataGenerationModelUnavailableError);
-});
-
-test("loads DeepSeek models, GLM, and an explicit keyless Qwen endpoint from installation setup", () => {
-  const { installationFile, secretsFile } = metadataConfiguration(`metadataGeneration:
-  default: glm-53
-  models:
-    - id: deepseek-v4-pro
-      label: DeepSeek V4 Pro
-      litellm: {provider: deepseek, model: deepseek-v4-pro}
-      apiKeyEnv: DEEPSEEK_API_KEY
-    - id: deepseek-v4-flash
-      label: DeepSeek V4 Flash
-      litellm: {provider: deepseek, model: deepseek-v4-flash}
-      apiKeyEnv: DEEPSEEK_API_KEY
-    - id: glm-53
-      label: GLM 5.3
-      litellm:
-        provider: openai
-        model: glm-5.3
-        endpoint: {baseUrl: https://api.z.ai/api/coding/paas/v4}
-      apiKeyEnv: ZAI_API_KEY
-    - id: qwen-36
-      label: Qwen 3.6
-      litellm:
-        provider: openai
-        model: qwen3.6-35b-a3b
-        disableThinking: true
-        endpoint: {baseUrl: https://models.internal.example/v1}
-`, "DEEPSEEK_API_KEY=deepseek-secret\nZAI_API_KEY=zai-secret\n");
-
-  const models = loadMetadataGenerationModels({ installationFile, secretsFile });
-
-  expect(models.catalog()).toEqual({
+  const catalog = {
+    schemaVersion: 1,
+    defaultSession: "zai/glm-5.3",
+    defaultMetadataGeneration: "zai/glm-5.3",
+    embedding: { id: "ollama/qwen3-embedding:0.6b", dimensions: 1024 },
     models: [
-      { id: "deepseek-v4-pro", label: "DeepSeek V4 Pro" },
-      { id: "deepseek-v4-flash", label: "DeepSeek V4 Flash" },
-      { id: "glm-53", label: "GLM 5.3" },
-      { id: "qwen-36", label: "Qwen 3.6" },
+      {
+        id: "zai/glm-5.3", provider: "zai", model: "glm-5.3", label: "GLM 5.3",
+        upstreamModel: "glm-5.3", endpoint: { baseUrl: "https://api.z.ai/v1" },
+        authentication: { mode: "secret_env", apiKeyEnv: "OPENAI_API_KEY" },
+        sessionAdapter: { mode: "openai_compatible" },
+        metadataAdapter: { litellmProvider: "openai" },
+        session: { reasoning: true, contextWindow: 200000, maxTokens: 131072 },
+        metadataGeneration: { disableThinking: false },
+      },
+      {
+        id: "deepseek/deepseek-v4-pro", provider: "deepseek", model: "deepseek-v4-pro",
+        label: "DeepSeek V4 Pro", upstreamModel: "deepseek-v4-pro",
+        authentication: { mode: "pi_auth" }, sessionAdapter: { mode: "pi_builtin" },
+        session: { reasoning: false },
+      },
     ],
-    default: "glm-53",
+    ...overrides,
+  };
+  writeFileSync(catalogFile, JSON.stringify(catalog), { mode: 0o600 });
+  writeFileSync(secretsFile, secrets, { mode: 0o600 });
+  chmodSync(catalogFile, 0o600);
+  chmodSync(secretsFile, 0o600);
+  return { catalogFile, secretsFile };
+}
+
+test("loads session default and safe metadata choices from the normalized runtime catalog", () => {
+  const { catalogFile, secretsFile } = runtimeCatalog();
+  const runtime = loadRuntimeModelCatalog(catalogFile);
+  const metadata = loadMetadataGenerationModels({ catalogFile, secretsFile });
+
+  expect(runtime.defaultSession).toBe("zai/glm-5.3");
+  expect(runtime.hasSession("deepseek/deepseek-v4-pro")).toBe(true);
+  expect(metadata.catalog()).toEqual({
+    models: [{ id: "zai/glm-5.3", label: "GLM 5.3" }],
+    default: "zai/glm-5.3",
   });
-  expect(models.resolve("deepseek-v4-pro")).toMatchObject({
-    apiKeyEnv: "DEEPSEEK_API_KEY",
-    apiKey: "deepseek-secret",
-  });
-  expect(models.resolve("qwen-36")).toEqual({
-    id: "qwen-36",
-    provider: "openai",
-    model: "qwen3.6-35b-a3b",
-    disableThinking: true,
-    endpoint: { baseUrl: "https://models.internal.example/v1" },
+  expect(metadata.resolve("zai/glm-5.3")).toEqual({
+    id: "zai/glm-5.3", provider: "openai", model: "glm-5.3",
+    endpoint: { baseUrl: "https://api.z.ai/v1" },
+    apiKeyEnv: "OPENAI_API_KEY", apiKey: "raw-provider-secret",
   });
+  expect(() => metadata.resolve("zai/missing")).toThrow(MetadataGenerationModelUnavailableError);
 });
 
-test("loads an explicit keyless endpoint without a secret bundle", () => {
-  const { installationFile } = metadataConfiguration(`metadataGeneration:
-  default: qwen-36
-  models:
-    - id: qwen-36
-      label: Qwen 3.6
-      litellm:
-        provider: openai
-        model: qwen3.6-35b-a3b
-        disableThinking: true
-        endpoint: {baseUrl: https://models.internal.example/v1}
-`);
+test("returns empty catalogs when no runtime projection is configured", () => {
+  expect(loadRuntimeModelCatalog().defaultSession).toBeNull();
+  expect(loadMetadataGenerationModels({}).catalog()).toEqual({ models: [], default: null });
+});
 
-  expect(loadMetadataGenerationModels({ installationFile }).resolve("qwen-36")).toEqual({
-    id: "qwen-36",
-    provider: "openai",
-    model: "qwen3.6-35b-a3b",
-    disableThinking: true,
-    endpoint: { baseUrl: "https://models.internal.example/v1" },
+test("rejects a drifted default and an unprotected projection", () => {
+  const drifted = runtimeCatalog({ defaultSession: "zai/missing" });
+  expect(() => loadRuntimeModelCatalog(drifted.catalogFile)).toThrow("session default is invalid");
+
+  const unprotected = runtimeCatalog();
+  chmodSync(unprotected.catalogFile, 0o666);
+  expect(() => loadRuntimeModelCatalog(unprotected.catalogFile)).toThrow("runtime model catalog is unavailable");
+});
+
+test("rejects authentication semantics that cannot come from the installation catalog", () => {
+  const invalid = runtimeCatalog({
+    defaultMetadataGeneration: undefined,
+    models: [{
+      id: "zai/glm-5.3",
+      provider: "zai",
+      model: "glm-5.3",
+      label: "GLM 5.3",
+      upstreamModel: "glm-5.3",
+      authentication: { mode: "secret_env" },
+      sessionAdapter: { mode: "pi_builtin" },
+      session: { reasoning: true },
+    }],
   });
+  expect(() => loadRuntimeModelCatalog(invalid.catalogFile)).toThrow("runtime model catalog is invalid");
 });
 
-test.each([
-  ["invalid YAML", "metadataGeneration: [\n", "OPENAI_API_KEY=secret\n", /invalid YAML/],
-  ["duplicate ids", `metadataGeneration:
-  default: openai-mini
-  models:
-    - {id: openai-mini, label: One, litellm: {provider: openai, model: gpt-4.1-mini}, apiKeyEnv: OPENAI_API_KEY}
-    - {id: openai-mini, label: Two, litellm: {provider: openai, model: gpt-4.1}, apiKeyEnv: OPENAI_API_KEY}
-`, "OPENAI_API_KEY=secret\n", /model id "openai-mini" is duplicated/],
-  ["missing default", `metadataGeneration:
-  models:
-    - {id: openai-mini, label: One, litellm: {provider: openai, model: gpt-4.1-mini}, apiKeyEnv: OPENAI_API_KEY}
-`, "OPENAI_API_KEY=secret\n", /default is required/],
-  ["unknown default", `metadataGeneration:
-  default: absent
-  models:
-    - {id: openai-mini, label: One, litellm: {provider: openai, model: gpt-4.1-mini}, apiKeyEnv: OPENAI_API_KEY}
-`, "OPENAI_API_KEY=secret\n", /default "absent" is not configured/],
-  ["malformed settings", `metadataGeneration:
-  default: openai-mini
-  models:
-    - {id: openai-mini, label: One, litellm: {provider: "open ai", model: gpt-4.1-mini}, apiKeyEnv: OPENAI_API_KEY}
-`, "OPENAI_API_KEY=secret\n", /configuration is invalid/],
-  ["malformed endpoint", `metadataGeneration:
-  default: openai-mini
-  models:
-    - id: openai-mini
-      label: One
-      litellm: {provider: openai, model: gpt-4.1-mini, endpoint: {baseUrl: not-a-url}}
-      apiKeyEnv: OPENAI_API_KEY
-`, "OPENAI_API_KEY=secret\n", /configuration is invalid/],
-  ["keyless hosted model without endpoint", `metadataGeneration:
-  default: openai-mini
-  models:
-    - {id: openai-mini, label: One, litellm: {provider: openai, model: gpt-4.1-mini}}
-`, "", /configuration is invalid/],
-  ["disable thinking without endpoint", `metadataGeneration:
-  default: openai-mini
-  models:
-    - id: openai-mini
-      label: One
-      litellm: {provider: openai, model: gpt-4.1-mini, disableThinking: true}
-      apiKeyEnv: OPENAI_API_KEY
-`, "OPENAI_API_KEY=secret\n", /configuration is invalid/],
-  ["unallowed secret reference", `metadataGeneration:
-  default: openai-mini
-  models:
-    - {id: openai-mini, label: One, litellm: {provider: openai, model: gpt-4.1-mini}, apiKeyEnv: THT_DWH_API_KEY}
-`, "THT_DWH_API_KEY=secret\n", /configuration is invalid/],
-  ["missing referenced secret", `metadataGeneration:
-  default: openai-mini
-  models:
-    - {id: openai-mini, label: One, litellm: {provider: openai, model: gpt-4.1-mini}, apiKeyEnv: OPENAI_API_KEY}
-`, "THT_DWH_API_KEY=secret\n", /secret "OPENAI_API_KEY" is missing/],
-  ["unusable referenced secret", `metadataGeneration:
-  default: openai-mini
-  models:
-    - {id: openai-mini, label: One, litellm: {provider: openai, model: gpt-4.1-mini}, apiKeyEnv: OPENAI_API_KEY}
-`, "OPENAI_API_KEY=secret with whitespace\n", /secret "OPENAI_API_KEY" is unusable/],
-] as const)("rejects %s metadata-generation configuration", (_name, yaml, secrets, expected) => {
-  const { installationFile, secretsFile } = metadataConfiguration(yaml, secrets);
-  expect(() => loadMetadataGenerationModels({ installationFile, secretsFile })).toThrow(expected);
+test("fails closed for missing or unusable provider secrets", () => {
+  const missing = runtimeCatalog({}, "THT_DWH_API_KEY=other\n");
+  expect(() => loadMetadataGenerationModels(missing)).toThrow('secret "OPENAI_API_KEY" is missing');
+
+  const unusable = runtimeCatalog({}, "OPENAI_API_KEY=contains whitespace\n");
+  expect(() => loadMetadataGenerationModels(unusable)).toThrow('secret "OPENAI_API_KEY" is unusable');
 });
 
-test("rejects a missing secret-bundle declaration for configured models", () => {
-  const { installationFile } = metadataConfiguration(`metadataGeneration:
-  default: openai-mini
-  models:
-    - {id: openai-mini, label: One, litellm: {provider: openai, model: gpt-4.1-mini}, apiKeyEnv: OPENAI_API_KEY}
-`);
-
-  expect(() => loadMetadataGenerationModels({ installationFile }))
-    .toThrow("metadata-generation keyed models require THT_SECRETS_FILE");
+test("splits canonical session identities without provider aliases", () => {
+  expect(splitCanonicalModelId("zai/glm-5.3")).toEqual({ provider: "zai", model: "glm-5.3" });
+  expect(() => splitCanonicalModelId("glm-5.3")).toThrow("model identity is invalid");
 });

backend/test/pi-management.test.ts

@@ -1,13 +1,13 @@
-import { mkdtempSync, readFileSync, readdirSync, rmSync } from "node:fs";
+import { mkdtempSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { expect, test, vi } from "vitest";
 import { loadConfig } from "../src/config.js";
 import {
-  PiManagementError,
   createPiManagement,
   type PiExecFile,
 } from "../src/pi/management.js";
+import type { RuntimeModelCatalog } from "../src/models/runtime-model-catalog.js";
 
 function configFor(settingsFile = join(mkdtempSync(join(tmpdir(), "tht-pi-management-")), "settings.json")) {
   return loadConfig({
@@ -18,10 +18,14 @@ function configFor(settingsFile = join(mkdtempSync(join(tmpdir(), "tht-pi-manage
   });
 }
 
-const supportedModels = [
-  { provider: "zai", id: "glm-5.2", name: "GLM 5.2", reasoning: true },
-  { provider: "deepseek", id: "deepseek-v4", name: "DeepSeek V4", reasoning: true },
-];
+const modelCatalog: RuntimeModelCatalog = {
+  defaultSession: "zai/glm-5.2",
+  defaultMetadataGeneration: null,
+  embedding: { id: "ollama/qwen3-embedding:0.6b", dimensions: 1024 },
+  sessionModels: () => [],
+  metadataModels: () => [],
+  hasSession: (id) => id === "zai/glm-5.2",
+};
 
 function successfulExec(calls: Array<{ command: string; args: string[]; timeout: number }>): PiExecFile {
   return async (command, args, options) => {
@@ -36,7 +40,7 @@ test("status parses only a Pi version from a fixed execFile argument array", asy
   const calls: Array<{ command: string; args: string[]; timeout: number }> = [];
   const service = createPiManagement(configFor(), {
     execute: successfulExec(calls),
-    listModels: async () => supportedModels,
+    modelCatalog,
     readSettings: () => ({ provider: "zai", model: "glm-5.2", thinking: "medium" }),
     credentialStatus: () => "missing",
     now: () => new Date("2026-08-05T10:00:00.000Z"),
@@ -63,7 +67,7 @@ test.each(["present", "missing"] as const)(
     const checkedProviders: Array<string | undefined> = [];
     const service = createPiManagement(configFor(), {
       execute: successfulExec([]),
-      listModels: async () => supportedModels,
+      modelCatalog,
       readSettings: () => ({ provider: "zai", model: "glm-5.2", thinking: "medium" }),
       credentialStatus: (provider) => {
         checkedProviders.push(provider);
@@ -85,100 +89,6 @@ test.each(["present", "missing"] as const)(
   },
 );
 
-// Catches an options response that leaks provider metadata or lets callers choose model IDs that
-// Pi did not explicitly enable for this installation.
-test("options expose only closed provider, model, and reasoning choices", async () => {
-  const service = createPiManagement(configFor(), {
-    execute: successfulExec([]),
-    listModels: async () => supportedModels,
-    now: () => new Date("2026-08-05T10:00:00.000Z"),
-  });
-
-  await expect(service.options()).resolves.toEqual({
-    providers: ["zai", "deepseek"],
-    models: [
-      { provider: "zai", id: "glm-5.2" },
-      { provider: "deepseek", id: "deepseek-v4" },
-    ],
-    reasoning: ["low", "medium", "high"],
-    checkedAt: "2026-08-05T10:00:00.000Z",
-  });
-});
-
-// Catches raw managed models.json validation details being collapsed into an ambiguous model-list
-// failure or escaping through the Pi Management options API.
-test("options report invalid managed model configuration with a stable sanitized error", async () => {
-  const service = createPiManagement(configFor(), {
-    execute: successfulExec([]),
-    listModels: async () => {
-      throw Object.assign(
-        new Error("!sensitive-command /private/models.json raw-secret"),
-        { code: "PI_MANAGED_CONFIG_INVALID" },
-      );
-    },
-  });
-
-  let caught: unknown;
-  try {
-    await service.options();
-  } catch (error) {
-    caught = error;
-  }
-  expect(caught).toMatchObject<PiManagementError>({
-    code: "pi_management_unavailable",
-    message: "Pi provider/model configuration is invalid",
-  });
-  expect(String(caught)).not.toMatch(/sensitive|private|models\.json|secret/i);
-});
-
-// Catches configuration writes that accept whitespace, unknown choices, or extra free-form fields
-// before reaching the durable installation settings file.
-test("config rejects invalid free-form values before writing settings", async () => {
-  const directory = mkdtempSync(join(tmpdir(), "tht-pi-management-invalid-"));
-  try {
-    let writes = 0;
-    const service = createPiManagement(configFor(join(directory, "settings.json")), {
-      execute: successfulExec([]),
-      listModels: async () => supportedModels,
-      readSettings: () => ({}),
-      saveSettings: () => { writes += 1; return {}; },
-    });
-
-    await expect(service.configure({
-      provider: "zai ", model: "glm-5.2", reasoning: "medium", unexpected: "value",
-    } as any)).rejects.toMatchObject<PiManagementError>({ code: "pi_management_invalid_config" });
-    expect(writes).toBe(0);
-  } finally {
-    rmSync(directory, { recursive: true, force: true });
-  }
-});
-
-// Catches a non-atomic implementation that can leave partial settings or temporary files after a
-// normal installation-default update.
-test("config validates closed choices and atomically persists non-secret defaults", async () => {
-  const directory = mkdtempSync(join(tmpdir(), "tht-pi-management-write-"));
-  const settingsFile = join(directory, "settings.json");
-  try {
-    const service = createPiManagement(configFor(settingsFile), {
-      execute: successfulExec([]),
-      listModels: async () => supportedModels,
-      now: () => new Date("2026-08-05T10:00:00.000Z"),
-    });
-
-    await expect(service.configure({
-      provider: "zai", model: "glm-5.2", reasoning: "high",
-    })).resolves.toEqual({
-      provider: "zai", model: "glm-5.2", reasoning: "high", updatedAt: "2026-08-05T10:00:00.000Z",
-    });
-    expect(JSON.parse(readFileSync(settingsFile, "utf8"))).toEqual({
-      provider: "zai", model: "glm-5.2", thinking: "high",
-    });
-    expect(readdirSync(directory)).toEqual(["settings.json"]);
-  } finally {
-    rmSync(directory, { recursive: true, force: true });
-  }
-});
-
 // Catches a hung Pi smoke check that leaves an operator waiting indefinitely or returns raw child
 // diagnostics containing provider credentials.
 test("smoke uses the configured timeout and reports a sanitized timeout", async () => {
@@ -188,7 +98,7 @@ test("smoke uses the configured timeout and reports a sanitized timeout", async
       calls.push({ command, args, timeout: options.timeout });
       throw Object.assign(new Error("provider token=raw-provider-token"), { code: "ETIMEDOUT" });
     },
-    listModels: async () => supportedModels,
+    modelCatalog,
     readSettings: () => ({ provider: "zai", model: "glm-5.2", thinking: "medium" }),
     now: () => new Date("2026-08-05T10:00:00.000Z"),
   });
@@ -210,7 +120,7 @@ test("smoke exercises the configured provider and model", async () => {
   const providerChecks: unknown[] = [];
   const service = createPiManagement(configFor(), {
     execute: successfulExec([]),
-    listModels: async () => supportedModels,
+    modelCatalog,
     readSettings: () => ({ provider: "zai", model: "glm-5.2", thinking: "medium" }),
     smokeProvider: async (request) => { providerChecks.push(request); },
     now: () => new Date("2026-08-05T10:00:00.000Z"),
@@ -230,7 +140,7 @@ test("smoke exercises the configured provider and model", async () => {
 test("smoke fails closed and sanitizes configured-provider authentication errors", async () => {
   const service = createPiManagement(configFor(), {
     execute: successfulExec([]),
-    listModels: async () => supportedModels,
+    modelCatalog,
     readSettings: () => ({ provider: "zai", model: "glm-5.2", thinking: "medium" }),
     smokeProvider: async () => {
       throw new Error('401 {"token":"raw-expired-token","output":"raw-provider-output"}');
@@ -252,7 +162,7 @@ test("smoke fails closed and sanitizes configured-provider authentication errors
 test("smoke reports invalid managed provider configuration with a stable sanitized error", async () => {
   const service = createPiManagement(configFor(), {
     execute: successfulExec([]),
-    listModels: async () => supportedModels,
+    modelCatalog,
     readSettings: () => ({ provider: "zai", model: "glm-5.2", thinking: "medium" }),
     smokeProvider: async () => {
       throw Object.assign(
@@ -284,7 +194,7 @@ test("smoke applies one deadline across version and a hung provider turn", async
         () => resolve({ stdout: "pi 0.80.3\n", stderr: "" }),
         500,
       )),
-      listModels: async () => supportedModels,
+      modelCatalog,
       readSettings: () => ({ provider: "zai", model: "glm-5.2", thinking: "medium" }),
       smokeProvider: async ({ timeoutMs }) => {
         providerTimeouts.push(timeoutMs);
@@ -320,7 +230,7 @@ test("logs keep only the latest 200 redacted lines", async () => {
   source[201] = "THT_MODEL_API_KEY=raw-env-secret";
   const service = createPiManagement(configFor(), {
     execute: successfulExec([]),
-    listModels: async () => supportedModels,
+    modelCatalog,
     readLogs: () => source.join("\n"),
     now: () => new Date("2026-08-05T10:00:00.000Z"),
   });

backend/test/pi-process-manager.test.ts

@@ -8,6 +8,7 @@ import {
 } from "node:fs";
 import { tmpdir } from "node:os";
 import { PiProcessManager } from "../src/pi/pi-process-manager.js";
+import type { RuntimeModelCatalog, RuntimeModel } from "../src/models/runtime-model-catalog.js";
 import { loadConfig } from "../src/config.js";
 import {
   PI_MANAGED_CONFIG_ERROR_MESSAGE,
@@ -641,6 +642,53 @@ test("session Pi spawn reads the single secret bundle and scrubs its path", asyn
   }
 });
 
+test("session Pi spawn resolves the selected catalog credential from the secret bundle", () => {
+  const root = mkdtempSync(path.join(tmpdir(), "thothii-catalog-credential-"));
+  const agentDir = path.join(root, "agent");
+  mkdirSync(agentDir, { mode: 0o700 });
+  writeFileSync(path.join(agentDir, "auth.json"), "{}\n", { mode: 0o600 });
+  writeFileSync(path.join(agentDir, "models.json"), '{"providers":{}}\n', { mode: 0o600 });
+  const secret = path.join(root, "thothii.secrets");
+  writeFileSync(secret, "ZAI_API_KEY=catalog-secret\nTHT_MODEL_API_KEY=legacy-secret\n", { mode: 0o600 });
+  const model: RuntimeModel = {
+    id: "openai/test-model",
+    provider: "openai",
+    model: "test-model",
+    label: "Test model",
+    upstreamModel: "test-model",
+    authentication: { mode: "secret_env", apiKeyEnv: "ZAI_API_KEY" },
+    sessionAdapter: { mode: "pi_builtin" },
+    session: { reasoning: false },
+  };
+  const modelCatalog: RuntimeModelCatalog = {
+    defaultSession: model.id,
+    defaultMetadataGeneration: null,
+    embedding: null,
+    sessionModels: () => [model],
+    metadataModels: () => [],
+    hasSession: (id) => id === model.id,
+  };
+  const calls: any[][] = [];
+  const child = recordingChild();
+  child.stderr.resume = () => {};
+  vi.stubEnv("PI_CODING_AGENT_DIR", agentDir);
+  const mgr = new PiProcessManager(loadConfig({ THT_SECRETS_FILE: secret }), {
+    modelCatalog,
+    authProviders: () => new Set(),
+    spawnFn: (...args: any[]) => { calls.push(args); return child as any; },
+  });
+  try {
+    mgr.createFor("catalog-credential", { provider: "openai", model: "test-model" });
+    expect(calls[0][2].env.ZAI_API_KEY).toBe("catalog-secret");
+    expect(calls[0][2].env).not.toHaveProperty("OPENAI_API_KEY");
+    expect(calls[0][2].env).not.toHaveProperty("THT_MODEL_API_KEY");
+  } finally {
+    mgr.teardown("catalog-credential");
+    vi.unstubAllEnvs();
+    rmSync(root, { recursive: true, force: true });
+  }
+});
+
 test.each([["OpenAI", "openai"], ["gemini", "google"]])(
   "set_model uses canonical packaged provider ID for %s", async (provider, canonical) => {
     const secret = path.resolve(__dirname, `.canonical-key-${process.pid}-${provider}`);

backend/test/pi-provider-smoke.test.ts

@@ -1,9 +1,11 @@
 import { EventEmitter } from "node:events";
-import { existsSync, readFileSync, readdirSync } from "node:fs";
-import { dirname } from "node:path";
+import { existsSync, mkdtempSync, readFileSync, readdirSync, rmSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { dirname, join } from "node:path";
 import { afterEach, expect, test, vi } from "vitest";
 import { loadConfig } from "../src/config.js";
 import { createPiProviderSmoke } from "../src/pi/provider-smoke.js";
+import type { RuntimeModel, RuntimeModelCatalog } from "../src/models/runtime-model-catalog.js";
 
 afterEach(() => vi.unstubAllEnvs());
 
@@ -44,6 +46,50 @@ function successfulProviderChild() {
 
 const MANAGED_CONFIG_ERROR = "Pi provider/model configuration is invalid";
 
+test("provider smoke resolves the selected catalog credential from the secret bundle", async () => {
+  const root = mkdtempSync(join(tmpdir(), "thothii-smoke-catalog-credential-"));
+  const secret = join(root, "thothii.secrets");
+  writeFileSync(secret, "ZAI_API_KEY=catalog-secret\nTHT_MODEL_API_KEY=legacy-secret\n", { mode: 0o600 });
+  const model: RuntimeModel = {
+    id: "openai/test-model",
+    provider: "openai",
+    model: "test-model",
+    label: "Test model",
+    upstreamModel: "test-model",
+    authentication: { mode: "secret_env", apiKeyEnv: "ZAI_API_KEY" },
+    sessionAdapter: { mode: "pi_builtin" },
+    session: { reasoning: false },
+  };
+  const modelCatalog: RuntimeModelCatalog = {
+    defaultSession: model.id,
+    defaultMetadataGeneration: null,
+    embedding: null,
+    sessionModels: () => [model],
+    metadataModels: () => [],
+    hasSession: (id) => id === model.id,
+  };
+  let spawnEnv: NodeJS.ProcessEnv | undefined;
+  const smoke = createPiProviderSmoke(loadConfig({ THT_SECRETS_FILE: secret }), {
+    modelCatalog,
+    authProviders: () => new Set(),
+    readModelsStore: () => undefined,
+    spawnFn: (_command, _args, options) => {
+      spawnEnv = options.env;
+      return successfulProviderChild();
+    },
+  });
+  try {
+    await expect(smoke({
+      provider: "openai", model: "test-model", reasoning: "medium", timeoutMs: 750,
+    })).resolves.toBeUndefined();
+    expect(spawnEnv?.ZAI_API_KEY).toBe("catalog-secret");
+    expect(spawnEnv).not.toHaveProperty("OPENAI_API_KEY");
+    expect(spawnEnv).not.toHaveProperty("THT_MODEL_API_KEY");
+  } finally {
+    rmSync(root, { recursive: true, force: true });
+  }
+});
+
 // Catches an isolated smoke agent that copies auth.json but drops the selected custom
 // provider/model from models.json, causing set_model to fail before the real request.
 test("provider smoke reaches the selected custom provider from an isolated models.json", async () => {

backend/test/readiness-manager.test.ts

@@ -2,18 +2,11 @@ import { expect, test } from "vitest";
 import { ReadinessManager } from "../src/runtime/readiness-manager.js";
 
 const workspace = {
-  workspace: { schema_version: 3, id: "psd", name: "PSD", language: "it" },
+  workspace: { schema_version: 4, id: "psd", name: "PSD", language: "it" },
   dwh: {
     engine: "postgres", database: "warehouse", schema: "public",
     supported_transports: ["postgres_direct"],
   },
-  semantic_index: {
-    vector_store: { engine: "qdrant", collection: "psd", dimensions: 1024, distance: "cosine" },
-    embedding: {
-      provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024,
-    },
-  },
-  llm_policy: { allowed: ["zai/glm-5.2"] },
 } as const;
 
 function deferred<T>() {

backend/test/registry-annotations.test.ts

@@ -15,7 +15,7 @@ afterEach(() => {
 });
 
 const validYaml = `workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: it
@@ -24,18 +24,6 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: psd-clinical
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 `;
 
 async function git(cwd: string, args: string[]): Promise<string> {

backend/test/registry-evidence.test.ts

@@ -20,7 +20,7 @@ async function git(cwd: string, args: string[]): Promise<string> {
 }
 
 const descriptor = `workspace:
-  schema_version: 3
+  schema_version: 4
   id: research
   name: Research
   language: en
@@ -29,18 +29,6 @@ dwh:
   database: analytics
   schema: mart
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: research
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 evidence:
   source:
     type: filesystem

backend/test/routes-pi-management.test.ts

@@ -14,11 +14,6 @@ function fakeService(): PiManagementService {
       config: { provider: "zai", model: "glm-5.2", reasoning: "medium" },
       checkedAt: "2026-08-05T10:00:00.000Z",
     })),
-    options: vi.fn(async () => ({
-      providers: ["zai"], models: [{ provider: "zai", id: "glm-5.2" }],
-      reasoning: ["low", "medium", "high"], checkedAt: "2026-08-05T10:00:00.000Z",
-    })),
-    configure: vi.fn(async (value) => ({ ...value, updatedAt: "2026-08-05T10:00:00.000Z" })),
     test: vi.fn(async () => ({ ready: true, checkedAt: "2026-08-05T10:00:00.000Z" })),
     logs: vi.fn(async () => ({ lines: ["Pi smoke check succeeded"], checkedAt: "2026-08-05T10:00:00.000Z" })),
   };
@@ -106,24 +101,17 @@ test("loopback-only AUTH_MODE=none may read the sanitized Pi status", async () =
 });
 
 // A local implicit administrator has pi.manage, but a browser origin still cannot borrow that
-// authority to mutate local configuration or trigger provider work.
+// authority to trigger provider work.
 test("loopback-only management rejects cross-origin writes for its local administrator", async () => {
   const service = fakeService();
   const app = appWith(service);
   try {
-    const configured = await app.inject({
-      method: "PUT", url: "/pi-management/config",
-      headers: { host: "127.0.0.1:8080", origin: "https://evil.example" },
-      payload: { provider: "zai", model: "glm-5.2", reasoning: "high" },
-    });
     const smoke = await app.inject({
       method: "POST", url: "/pi-management/test",
       headers: { host: "127.0.0.1:8080", origin: "https://evil.example" },
     });
 
-    expect(configured.statusCode).toBe(403);
     expect(smoke.statusCode).toBe(403);
-    expect(service.configure).not.toHaveBeenCalled();
     expect(service.test).not.toHaveBeenCalled();
   } finally {
     await app.close();
@@ -132,14 +120,13 @@ test("loopback-only management rejects cross-origin writes for its local adminis
 
 // Catches an origin guard that also blocks the same-origin Docker frontend or non-browser local
 // lifecycle clients that do not send Origin.
-test("loopback-only management preserves same-origin frontend and origin-less local writes", async () => {
+test("loopback-only management preserves same-origin and origin-less smoke checks", async () => {
   const service = fakeService();
   const app = appWith(service);
   try {
     const sameOrigin = await app.inject({
-      method: "PUT", url: "/pi-management/config",
+      method: "POST", url: "/pi-management/test",
       headers: { host: "127.0.0.1:8080", origin: "http://127.0.0.1:8080" },
-      payload: { provider: "zai", model: "glm-5.2", reasoning: "high" },
     });
     const lifecycleClient = await app.inject({ method: "POST", url: "/pi-management/test" });
 
@@ -150,25 +137,20 @@ test("loopback-only management preserves same-origin frontend and origin-less lo
   }
 });
 
-// Catches route wiring that bypasses closed service validation or gives the browser a Docker/image
-// lifecycle endpoint rather than only installation-default configuration and diagnostics.
-test("trusted admins receive only configuration, smoke, options, and log endpoints", async () => {
+// Catches a regression that reintroduces a browser-writable provider/model source.
+test("trusted admins receive only status, smoke, and log endpoints", async () => {
   const service = fakeService();
   const app = appWith(service, exposedServerEnv);
   try {
-    const options = await app.inject({ method: "GET", url: "/pi-management/options", headers: adminHeaders });
-    const configured = await app.inject({
-      method: "PUT", url: "/pi-management/config", headers: adminHeaders,
-      payload: { provider: "zai", model: "glm-5.2", reasoning: "high" },
-    });
+    const status = await app.inject({ method: "GET", url: "/pi-management/status", headers: adminHeaders });
     const smoke = await app.inject({ method: "POST", url: "/pi-management/test", headers: adminHeaders });
     const logs = await app.inject({ method: "GET", url: "/pi-management/logs", headers: adminHeaders });
 
-    expect(options.statusCode).toBe(200);
-    expect(configured.statusCode).toBe(200);
-    expect(configured.json()).toMatchObject({ provider: "zai", model: "glm-5.2", reasoning: "high" });
+    expect(status.statusCode).toBe(200);
     expect(smoke.statusCode).toBe(200);
     expect(logs.statusCode).toBe(200);
+    expect((await app.inject({ method: "GET", url: "/pi-management/options", headers: adminHeaders })).statusCode).toBe(404);
+    expect((await app.inject({ method: "PUT", url: "/pi-management/config", headers: adminHeaders })).statusCode).toBe(404);
     expect(app.printRoutes()).not.toContain("update");
     expect(app.printRoutes()).not.toContain("rollback");
   } finally {

backend/test/routes-sessions.test.ts

@@ -18,25 +18,25 @@ const SCRIPT = path.resolve("../harness/tests/fake_pi/scripts/f1_disambiguation.
 
 function operationalWorkspace(id = "default") {
   return {
-    workspace: { schema_version: 3, id, name: id, language: "en" },
+    workspace: { schema_version: 4, id, name: id, language: "en" },
     dwh: {
       engine: "postgres", database: "warehouse", schema: "public",
       supported_transports: ["postgres_direct"],
     },
-    semantic_index: {
-      vector_store: {
-        engine: "qdrant", collection: id, dimensions: 1024, distance: "cosine",
-      },
-      embedding: {
-        provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024,
-      },
-    },
-    llm_policy: {
-      allowed: ["zai/glm-5.2", "deepseek/deepseek-v4-pro", "local-qwen/qwen3.6-35b-a3b"],
-    },
   } as const;
 }
 
+function sessionCatalog(defaultSession = "zai/glm-5.2", available = [defaultSession]) {
+  return {
+    defaultSession,
+    defaultMetadataGeneration: null,
+    embedding: { id: "ollama/qwen3-embedding:0.6b", dimensions: 1024 },
+    sessionModels: () => [],
+    metadataModels: () => [],
+    hasSession: (id: string) => available.includes(id),
+  } as any;
+}
+
 const defaultWorkspaceRegistry = {
   list: vi.fn(async () => [{
     id: "default", commit: "e".repeat(40), blob: "f".repeat(40),
@@ -495,8 +495,8 @@ test("creates a session from the active immutable workspace revision", async ()
     workspaceRegistry: {
       read: vi.fn(async () => ({
         workspace: {
-          workspace: { schema_version: 2, id: "psd-clinical", name: "PSD", language: "it" },
-          dwh: {}, semantic_index: {}, llm_policy: { allowed: ["zai/glm-5.2"] },
+          workspace: { schema_version: 4, id: "psd-clinical", name: "PSD", language: "it" },
+          dwh: {},
         },
         revision: {
           id: "psd-clinical", commit: "a".repeat(40), blob: "b".repeat(40),
@@ -589,22 +589,11 @@ test("rejects an SSH-only workspace before persisting or starting a session", as
     workspaceRegistry: {
       acquireSessionRevision: vi.fn(async () => ({
         workspace: {
-          workspace: { schema_version: 2, id: "ssh-workspace", name: "SSH", language: "en" },
+          workspace: { schema_version: 4, id: "ssh-workspace", name: "SSH", language: "en" },
           dwh: {
             engine: "postgres", database: "postgres", schema: "public",
             supported_transports: ["ssh_tunnel"],
           },
-          semantic_index: {
-            vector_store: {
-              engine: "pgvector", database: "postgres", schema: "vectors",
-              collection: "documents", dimensions: 768, distance: "cosine",
-              supported_transports: ["ssh_tunnel"],
-            },
-            embedding: {
-              provider: "ollama_compatible", model: "nomic-embed-text", dimensions: 768,
-            },
-          },
-          llm_policy: { allowed: ["zai/glm-5.2"] },
         },
         revision: {
           id: "ssh-workspace", commit: "a".repeat(40), blob: "b".repeat(40),
@@ -632,7 +621,7 @@ test("hands a revision lease to retention only after the session manifest is dur
   const markPersisted = vi.fn(async () => {});
   const abort = vi.fn(async () => {});
   const acquireSessionRevision = vi.fn(async () => ({
-    workspace: { llm_policy: { allowed: ["zai/glm-5.2"] } },
+    workspace: operationalWorkspace("leased"),
     revision: {
       id: "leased", commit: "a".repeat(40), blob: "b".repeat(40),
       snapshotPath: `/data/workspace-registry/snapshots/${"a".repeat(40)}/leased.yaml`,
@@ -670,7 +659,7 @@ test("creates a session from the configured default workspace revision when work
   const sessionNew = vi.fn(async () => ({ id: "default-pinned" }));
   const registry = {
     read: vi.fn(async (id: string) => ({
-      workspace: { llm_policy: { allowed: ["zai/glm-5.2"] } },
+      workspace: operationalWorkspace(id),
       revision: {
         id, commit: "c".repeat(40), blob: "d".repeat(40),
         snapshotPath: `/data/workspace-registry/snapshots/${"c".repeat(40)}/${id}.yaml`,
@@ -758,7 +747,7 @@ test("session lifecycle locates a B session when installation default is A", asy
     listModels: async () => [{ provider: "zai", id: "glm-5.2", name: "GLM 5.2", reasoning: true }],
     workspaceRegistry: {
       read: async (id: string) => ({
-        workspace: { llm_policy: { allowed: ["zai/glm-5.2"] } },
+        workspace: operationalWorkspace(id),
         revision: { id, commit: "b".repeat(40), blob: "d".repeat(40), snapshotPath: bPath },
       }),
       list: async () => [
@@ -793,7 +782,7 @@ test("session lifecycle locates a B session when installation default is A", asy
   expect(runtimeOptions).toEqual(["/runtime/1.yaml", "/runtime/2.yaml"]);
 });
 
-test("POST /sessions usa i settings (workspace/provider/model/thinking) e crea+avvia", async () => {
+test("POST /sessions uses the catalog default with workspace/thinking settings and starts", async () => {
   const modelKey = path.join(os.tmpdir(), `thoth-model-key-${process.pid}`);
   writeFileSync(modelKey, "test-model-key", { mode: 0o600 });
   chmodSync(modelKey, 0o600);
@@ -808,7 +797,8 @@ test("POST /sessions usa i settings (workspace/provider/model/thinking) e crea+a
       sessionNew: async (o: any) => { sessionNewArg = o; return { id: "s1" }; },
       sessionList: async () => [{ id: "s1" }],
     } as any,
-    getSettings: () => ({ workspace: "w", provider: "zai", model: "glm-5.2", thinking: "high" }),
+    getSettings: () => ({ workspace: "w", thinking: "high" }),
+    runtimeModelCatalog: sessionCatalog(),
     listModels: async () => [
       { provider: "zai", id: "glm-5.2", name: "GLM 5.2", reasoning: true },
     ],
@@ -2565,32 +2555,43 @@ test("POST /sessions proceeds when ollamaEnsure succeeds", async () => {
   expect(ensureWs).toContain(`/snapshots/${"e".repeat(40)}/psd.yaml`);
 });
 
-test("POST /sessions rejects an unavailable saved model before persisting a session", async () => {
+test("POST /sessions falls back from a stale requested model to the catalog default", async () => {
   let created = 0;
+  let persisted: any;
+  const runtime = { bridge: { onClientEvent: () => {} } };
   const app = buildApp(loadConfig({ THT_HARNESS_DIR: "../harness" }), {
     thtRunner: {
-      sessionNew: async () => { created += 1; return { id: "must-not-exist" }; },
+      sessionNew: async (options: any) => { created += 1; persisted = options; return { id: "fallback" }; },
+      searchPack: async () => {},
     } as any,
     readiness: { ensure: async () => ({ ok: true }) } as any,
-    getSettings: () => ({
-      workspace: "psd",
-      provider: "deepseek",
-      model: "deepseek-v4-pro",
-      thinking: "medium",
-    }) as any,
+    getSettings: () => ({ workspace: "psd", thinking: "medium" }) as any,
+    runtimeModelCatalog: sessionCatalog(),
     listModels: async () => [
       { provider: "zai", id: "glm-5.2", name: "GLM 5.2", reasoning: true },
     ],
+    mgr: {
+      teardownForPrincipal: () => [],
+      createFor: () => runtime,
+      get: () => runtime,
+      configure: async () => {},
+      start: () => {},
+    } as any,
   });
 
-  const res = await app.inject({ method: "POST", url: "/sessions", payload: { question: "q" } });
+  const res = await app.inject({
+    method: "POST",
+    url: "/sessions",
+    payload: { question: "q", provider: "deepseek", model: "deepseek-v4-pro" },
+  });
 
-  expect(res.statusCode).toBe(503);
+  expect(res.statusCode).toBe(200);
   expect(res.json()).toEqual({
-    error: "Selected model is unavailable. Check Pi authentication and model settings, then try again.",
-    code: "model_unavailable",
+    id: "fallback",
+    warning: "Configured model deepseek/deepseek-v4-pro is unavailable; using zai/glm-5.2.",
   });
-  expect(created).toBe(0);
+  expect(persisted).toMatchObject({ provider: "zai", model: "glm-5.2" });
+  expect(created).toBe(1);
 });
 
 test("POST /sessions marks a persisted session failed when runtime construction throws", async () => {

backend/test/routes-settings.test.ts

@@ -21,7 +21,7 @@ function appWithTmpSettings(extraEnv: Record<string, string> = {}, deps = {}) {
   return { app, dir };
 }
 
-test("GET /settings returns effective defaults (env provider/model/thinking, first workspace)", async () => {
+test("GET /settings returns thinking and the first workspace without legacy model defaults", async () => {
   const { app, dir } = appWithTmpSettings({ PI_PROVIDER: "zai", PI_MODEL: "glm-5.2", PI_THINKING: "medium" }, {
     listModels: async () => [{ provider: "zai", id: "glm-5.2", name: "GLM 5.2", reasoning: true }],
   });
@@ -29,8 +29,8 @@ test("GET /settings returns effective defaults (env provider/model/thinking, fir
     const res = await app.inject({ method: "GET", url: "/settings" });
     expect(res.statusCode).toBe(200);
     const body = res.json();
-    expect(body.provider).toBe("zai");
-    expect(body.model).toBe("glm-5.2");
+    expect(body).not.toHaveProperty("provider");
+    expect(body).not.toHaveProperty("model");
     expect(body.thinking).toBe("medium");
     expect(typeof body.workspace).toBe("string"); // first workspace from ../harness/workspaces
   } finally {
@@ -62,7 +62,9 @@ test("PUT /settings does not persist personal workspace or LLM choices", async (
     });
     expect(put.statusCode).toBe(200);
     const got = await app.inject({ method: "GET", url: "/settings" });
-    expect(got.json()).toMatchObject({ provider: "zai", model: "glm-5.2", thinking: "medium" });
+    expect(got.json()).toMatchObject({ thinking: "medium" });
+    expect(got.json()).not.toHaveProperty("provider");
+    expect(got.json()).not.toHaveProperty("model");
     expect(got.json()).not.toMatchObject({ workspace: "psd", thinking: "high" });
   } finally {
     rmSync(dir, { recursive: true, force: true });
@@ -114,7 +116,7 @@ test("settings no longer read or write principal-specific preferences", async ()
   expect(preferences.size).toBe(0);
 });
 
-test("GET /settings retains complete legacy installation defaults without seeding a private profile", async () => {
+test("GET /settings drops legacy installation model fields without seeding a private profile", async () => {
   let preferences: Record<string, unknown> = {};
   const writes: Record<string, unknown>[] = [];
   const runner = {
@@ -135,9 +137,7 @@ test("GET /settings retains complete legacy installation defaults without seedin
     const first = await app.inject({ method: "GET", url: "/settings" });
     const second = await app.inject({ method: "GET", url: "/settings" });
 
-    const expected = {
-      workspace: "local", provider: "local-qwen", model: "qwen3.6-35b-a3b", thinking: "low",
-    };
+    const expected = { workspace: "local", thinking: "low" };
     expect(first.statusCode).toBe(200);
     expect(first.json()).toEqual(expected);
     expect(second.json()).toEqual(expected);
@@ -167,15 +167,13 @@ test("GET /settings ignores stale private preferences in favor of installation d
     const response = await app.inject({ method: "GET", url: "/settings" });
 
     expect(response.statusCode).toBe(200);
-    expect(response.json()).toEqual({
-      workspace: "local", provider: "local-qwen", model: "qwen3.6-35b-a3b", thinking: "low",
-    });
+    expect(response.json()).toEqual({ workspace: "local", thinking: "low" });
   } finally {
     rmSync(dir, { recursive: true, force: true });
   }
 });
 
-test("PUT /settings rejects an unknown model when a model list is available", async () => {
+test("PUT /settings ignores a legacy unknown model because the catalog owns model validity", async () => {
   const { app, dir } = appWithTmpSettings({}, {
     listModels: async () => [{ provider: "zai", id: "glm-5.2", name: "GLM 5.2", reasoning: true }],
   });
@@ -184,14 +182,14 @@ test("PUT /settings rejects an unknown model when a model list is available", as
       method: "PUT", url: "/settings",
       payload: { workspace: "psd", provider: "zai", model: "does-not-exist", thinking: "low" },
     });
-    expect(put.statusCode).toBe(400);
-    expect(put.json()).toMatchObject({ error: expect.stringMatching(/model/i) });
+    expect(put.statusCode).toBe(200);
+    expect(put.json()).not.toHaveProperty("model");
   } finally {
     rmSync(dir, { recursive: true, force: true });
   }
 });
 
-test("PUT /settings validates provider and model as one composite identifier", async () => {
+test("PUT /settings ignores legacy provider/model pairs", async () => {
   const { app, dir } = appWithTmpSettings({}, {
     listModels: async () => [
       { provider: "provider-a", id: "shared-id", name: "A", reasoning: false },
@@ -204,7 +202,7 @@ test("PUT /settings validates provider and model as one composite identifier", a
         workspace: "psd", provider: "provider-b", model: "shared-id", thinking: "low",
       },
     });
-    expect(wrongProvider.statusCode).toBe(400);
+    expect(wrongProvider.statusCode).toBe(200);
 
     const exactPair = await app.inject({
       method: "PUT", url: "/settings",
@@ -213,6 +211,8 @@ test("PUT /settings validates provider and model as one composite identifier", a
       },
     });
     expect(exactPair.statusCode).toBe(200);
+    expect(exactPair.json()).not.toHaveProperty("provider");
+    expect(exactPair.json()).not.toHaveProperty("model");
   } finally {
     rmSync(dir, { recursive: true, force: true });
   }

backend/test/routes-sql-meta.test.ts

@@ -1,4 +1,4 @@
-import { test, expect, vi } from "vitest";
+import { test, expect } from "vitest";
 import Fastify from "fastify";
 import { buildApp } from "../src/app.js";
 import { loadConfig } from "../src/config.js";
@@ -156,12 +156,23 @@ test("registry-backed SQL preview resolves and uses the session's pinned runtime
 // Workspace registry route coverage lives in routes-workspaces.test.ts. `/workspaces` no longer
 // reads legacy harness files: the Git registry is the single shared source of truth.
 
-test("GET /models returns {models:[...]} from injected listModels stub", async () => {
+test("GET /models returns session choices from the installation model catalog", async () => {
   const app = buildApp(loadConfig({ THT_HARNESS_DIR: "../harness" }), {
     thtRunner: {} as any,
-    listModels: async () => [
-      { provider: "zai", id: "glm-5.2", name: "GLM 5.2", reasoning: true },
-    ],
+    runtimeModelCatalog: {
+      defaultSession: "zai/glm-5.2",
+      defaultMetadataGeneration: null,
+      embedding: { id: "ollama/qwen3-embedding:0.6b", dimensions: 1024 },
+      sessionModels: () => [{
+        id: "zai/glm-5.2", provider: "zai", model: "glm-5.2", label: "GLM 5.2",
+        upstreamModel: "glm-5.2", authentication: { mode: "pi_auth" },
+        sessionAdapter: { mode: "pi_builtin" }, session: { reasoning: true },
+      }],
+      metadataModels: () => [],
+      hasSession: (id: string) => id === "zai/glm-5.2",
+    },
+    // Runtime introspection is a health gate for starting a session, not a second catalog.
+    listModels: async () => { throw new Error("Pi is unavailable"); },
   });
 
   const res = await app.inject({ method: "GET", url: "/models" });
@@ -172,36 +183,17 @@ test("GET /models returns {models:[...]} from injected listModels stub", async (
   });
 });
 
-test("GET /models returns {models:[]} when listModels throws (graceful fallback)", async () => {
+test("GET /models returns an empty list when the catalog has no session models", async () => {
   const app = buildApp(loadConfig({ THT_HARNESS_DIR: "../harness" }), {
     thtRunner: {} as any,
-    listModels: async () => { throw new Error("Pi not running"); },
-  });
-
-  const res = await app.inject({ method: "GET", url: "/models" });
-
-  expect(res.statusCode).toBe(200);
-  expect(res.json()).toEqual({ models: [] });
-});
-
-test("GET /models logs a sanitized warning when listing fails", async () => {
-  const app = buildApp(loadConfig({ THT_HARNESS_DIR: "../harness" }), {
-    thtRunner: {} as any,
-    listModels: async () => { throw new Error("credential-value-must-not-appear"); },
-  });
-  const warn = vi.spyOn(app.log, "warn");
-
-  const res = await app.inject({ method: "GET", url: "/models" });
-
-  expect(res.json()).toEqual({ models: [] });
-  expect(JSON.stringify(warn.mock.calls)).not.toContain("credential-value-must-not-appear");
-  expect(warn).toHaveBeenCalled();
-});
-
-test("GET /models with empty listModels stub returns empty array", async () => {
-  const app = buildApp(loadConfig({ THT_HARNESS_DIR: "../harness" }), {
-    thtRunner: {} as any,
-    listModels: async () => [],
+    runtimeModelCatalog: {
+      defaultSession: null,
+      defaultMetadataGeneration: null,
+      embedding: null,
+      sessionModels: () => [],
+      metadataModels: () => [],
+      hasSession: () => false,
+    },
   });
 
   const res = await app.inject({ method: "GET", url: "/models" });

backend/test/routes-workspaces.test.ts

@@ -14,7 +14,7 @@ import type { AuthDiagnoser, AuthDiagnostics } from "../src/auth/diagnostics.js"
 
 const workspace: CanonicalWorkspace = {
   workspace: {
-    schema_version: 3,
+    schema_version: 4,
     id: "psd-clinical",
     name: "Policlinico San Donato",
     description: "Clinical analytics workspace",
@@ -26,20 +26,6 @@ const workspace: CanonicalWorkspace = {
     schema: "datawarehouse",
     supported_transports: ["postgres_direct"],
   },
-  semantic_index: {
-    vector_store: {
-      engine: "qdrant",
-      collection: "psd-clinical",
-      dimensions: 1024,
-      distance: "cosine",
-    },
-    embedding: {
-      provider: "ollama_internal",
-      model: "qwen3-embedding:0.6b",
-      dimensions: 1024,
-    },
-  },
-  llm_policy: { allowed: ["zai/glm-5.2"] },
 };
 
 const revision: WorkspaceRevision = {
@@ -194,7 +180,7 @@ test("lists workspace summaries and reads a validated immutable workspace", asyn
   expect(read.json()).toEqual({ workspace, revision });
 });
 
-test("validates a schema v3 workspace without mutating the repository", async () => {
+test("validates a schema v4 workspace without mutating the repository", async () => {
   const app = appFor(registryFake());
 
   const response = await app.inject({
@@ -284,7 +270,7 @@ test.each([1, 2])("rejects schema v%s at the validation boundary with a sanitize
   expect(response.body).not.toMatch(/migration_required|schema version/i);
 });
 
-test("runs diagnostics for a schema v3 workspace", async () => {
+test("runs diagnostics for a schema v4 workspace", async () => {
   const diagnose = vi.fn(async () => ({ activatable: true, diagnostics: [] }));
   const app = appFor(registryFake(), diagnose);
 

backend/test/settings-store.test.ts

@@ -27,9 +27,9 @@ test("saveSettings writes the file and loadSettings reads it back", () => {
   const dir = mkdtempSync(join(tmpdir(), "tht-set-"));
   try {
     const cfg = cfgWith(join(dir, "nested", "settings.json"));
-    const saved = saveSettings(cfg, { workspace: "psd", provider: "zai", model: "glm-5.2", thinking: "medium" });
-    expect(saved.model).toBe("glm-5.2");
-    expect(loadSettings(cfg)).toEqual({ workspace: "psd", provider: "zai", model: "glm-5.2", thinking: "medium" });
+    const saved = saveSettings(cfg, { workspace: "psd", thinking: "medium" });
+    expect(saved.thinking).toBe("medium");
+    expect(loadSettings(cfg)).toEqual({ workspace: "psd", thinking: "medium" });
   } finally {
     rmSync(dir, { recursive: true, force: true });
   }
@@ -55,11 +55,11 @@ test("saveSettings restores the previous file when post-rename directory durabil
   const dir = mkdtempSync(join(tmpdir(), "tht-set-transaction-"));
   try {
     const cfg = cfgWith(join(dir, "settings.json"));
-    saveSettings(cfg, { provider: "old", model: "old-model", thinking: "low" });
+    saveSettings(cfg, { thinking: "low" });
     let syncs = 0;
     expect(() => saveSettings(
       cfg,
-      { provider: "new", model: "new-model", thinking: "high" },
+      { thinking: "high" },
       {
         syncDirectory(directory: string) {
           syncs += 1;
@@ -69,7 +69,7 @@ test("saveSettings restores the previous file when post-rename directory durabil
         },
       },
     )).toThrow(/directory fsync failure/);
-    expect(loadSettings(cfg)).toEqual({ provider: "old", model: "old-model", thinking: "low" });
+    expect(loadSettings(cfg)).toEqual({ thinking: "low" });
     expect(syncs).toBeGreaterThanOrEqual(2);
   } finally {
     rmSync(dir, { recursive: true, force: true });

backend/test/tht-qdrant-readiness.test.ts

@@ -8,18 +8,11 @@ const keywordIndexes = [
 ];
 
 const workspace: CanonicalWorkspace = {
-  workspace: { schema_version: 3, id: "psd", name: "PSD", language: "it" },
+  workspace: { schema_version: 4, id: "psd", name: "PSD", language: "it" },
   dwh: {
     engine: "postgres", database: "warehouse", schema: "public",
     supported_transports: ["postgres_direct"],
   },
-  semantic_index: {
-    vector_store: { engine: "qdrant", collection: "psd", dimensions: 1024, distance: "cosine" },
-    embedding: {
-      provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024,
-    },
-  },
-  llm_policy: { allowed: ["zai/glm-5.2"] },
 };
 
 function runner(request: (...args: any[]) => Promise<any>) {

backend/test/workspace-preprocessing-service.test.ts

@@ -19,12 +19,13 @@ afterEach(() => {
 const semanticRuntime = {
   internalQdrantUrl: "http://qdrant:6333",
   internalEmbeddingUrl: "http://embedding:11434",
+  internalEmbeddingId: "ollama/qwen3-embedding:0.6b",
   internalEmbeddingModel: "qwen3-embedding:0.6b",
   internalEmbeddingDimensions: 1024,
 };
 
 const baseWorkspace = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Runtime Lease
   language: en
@@ -33,21 +34,9 @@ dwh:
   database: analytics
   schema: mart
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: psd-clinical
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 `);
 const filesystemWorkspace = parseWorkspaceYaml(`${baseWorkspace ? '' : ''}workspace:
-  schema_version: 3
+  schema_version: 4
   id: fs-workspace
   name: Filesystem
   language: en
@@ -56,25 +45,13 @@ dwh:
   database: analytics
   schema: mart
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: fs-workspace
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 evidence:
   source:
     type: filesystem
     uri: fs-workspace/evidence
 `);
 const privateHttpWorkspace = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: http-workspace
   name: Http
   language: en
@@ -83,18 +60,6 @@ dwh:
   database: analytics
   schema: mart
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: http-workspace
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 evidence:
   source:
     type: http
@@ -125,7 +90,7 @@ function runtime(workspace = baseWorkspace, workspaceId = workspace.workspace.id
       bindingDigest: "sha256:bindings",
       semanticQdrantUrl: "http://qdrant:6333",
       effectiveConfig: {
-        schemaVersion: 1,
+        schemaVersion: 2,
         dwh: {
           engine: "postgres",
           database: "analytics",
@@ -136,7 +101,7 @@ function runtime(workspace = baseWorkspace, workspaceId = workspace.workspace.id
           user: "reader",
         },
         vector: { collection: workspaceId, dimensions: 1024, distance: "cosine" },
-        embedding: { model: "qwen3-embedding:0.6b", dimensions: 1024 },
+        embedding: { id: "ollama/qwen3-embedding:0.6b", model: "qwen3-embedding:0.6b", dimensions: 1024 },
         roots: { artifacts: "/data/artifacts", indexes: "/data/indexes" },
       },
       effectiveConfigIdentity: "workspace://psd-clinical@v1:" + "d".repeat(64),

backend/test/workspace-preprocessing-state.test.ts

@@ -28,13 +28,15 @@ test("job state creates durable 0600 JSON and enforces same-revision resume", as
     catalogBlob: "c".repeat(40),
     configDigest: "sha256:config",
     bindingDigest: "sha256:bindings",
+    embeddingId: "ollama/qwen3-embedding:0.6b",
+    embeddingDimensions: 1024,
   });
 
   const path = store.jobPath(job.runId);
   expect(existsSync(path)).toBe(true);
   expect(statSync(path).mode & 0o777).toBe(0o600);
   expect(JSON.parse(readFileSync(path, "utf8"))).toMatchObject({
-    schemaVersion: 1,
+    schemaVersion: 2,
     operation: "preprocess dwh",
     workspaceId: "psd-clinical",
     workspaceRevision: "a".repeat(40),
@@ -42,6 +44,8 @@ test("job state creates durable 0600 JSON and enforces same-revision resume", as
     catalogBlob: "c".repeat(40),
     configDigest: "sha256:config",
     bindingDigest: "sha256:bindings",
+    embeddingId: "ollama/qwen3-embedding:0.6b",
+    embeddingDimensions: 1024,
   });
 
   await expect(store.beginJob({
@@ -52,6 +56,20 @@ test("job state creates durable 0600 JSON and enforces same-revision resume", as
     catalogBlob: "c".repeat(40),
     configDigest: "sha256:config",
     bindingDigest: "sha256:bindings",
+    embeddingId: "ollama/qwen3-embedding:0.6b",
+    embeddingDimensions: 1024,
+  })).rejects.toMatchObject({ code: "preprocessing_resume_mismatch" });
+
+  await expect(store.beginJob({
+    operation: "preprocess dwh",
+    runId: job.runId,
+    workspaceRevision: "a".repeat(40),
+    descriptorBlob: "b".repeat(40),
+    catalogBlob: "c".repeat(40),
+    configDigest: "sha256:config",
+    bindingDigest: "sha256:bindings",
+    embeddingId: "ollama/replacement-embedding",
+    embeddingDimensions: 1024,
   })).rejects.toMatchObject({ code: "preprocessing_resume_mismatch" });
 
   const resumed = await store.beginJob({
@@ -62,6 +80,8 @@ test("job state creates durable 0600 JSON and enforces same-revision resume", as
     catalogBlob: "c".repeat(40),
     configDigest: "sha256:config",
     bindingDigest: "sha256:bindings",
+    embeddingId: "ollama/qwen3-embedding:0.6b",
+    embeddingDimensions: 1024,
   });
   expect(resumed.runId).toBe(job.runId);
 });

backend/test/workspace-registry-deployment.test.ts

@@ -75,10 +75,6 @@ function workspaceVariant(
   return {
     ...workspace,
     workspace: { ...workspace.workspace, ...changes, id },
-    semantic_index: {
-      ...workspace.semantic_index,
-      vector_store: { ...workspace.semantic_index.vector_store, collection: id },
-    },
     ...(workspace.evidence?.source.type === "filesystem"
       ? {
           evidence: {
@@ -182,7 +178,7 @@ test("shared deployment fixtures remain valid standalone descriptors with canoni
 
   expect(smoke).toMatchObject({
     workspace: {
-      schema_version: 3,
+      schema_version: 4,
       id: "local",
       name: "Local",
       description: "Isolated workspace registry smoke fixture.",
@@ -193,14 +189,14 @@ test("shared deployment fixtures remain valid standalone descriptors with canoni
     },
   });
   expect(task13).toMatchObject({
-    workspace: { schema_version: 3, id: "task13-smoke", name: "Task 13 Smoke" },
+    workspace: { schema_version: 4, id: "task13-smoke", name: "Task 13 Smoke" },
     evidence: {
       source: { type: "filesystem", uri: "task13-smoke/evidence", patterns: ["**/*.md"] },
       policy: { max_chunk_chars: 4000, retain_published_generations: 3 },
     },
   });
   expect(windows).toMatchObject({
-    workspace: { schema_version: 3, id: "task13-windows", name: "Task 13 Windows" },
+    workspace: { schema_version: 4, id: "task13-windows", name: "Task 13 Windows" },
     evidence: {
       source: { type: "filesystem", uri: "task13-windows/evidence", patterns: ["**/*.md"] },
       policy: { max_chunk_chars: 4000, retain_published_generations: 3 },
@@ -282,7 +278,7 @@ test("registry rejects orphan descriptors, metadata mismatches, and the retired
   });
 });
 
-test("Windows clone contract copies the shared complete schema v3 descriptor into the nested registry layout", () => {
+test("Windows clone contract copies the shared complete schema v4 descriptor into the nested registry layout", () => {
   const descriptor = parseWorkspaceYaml(readFixture("workspace-registry-windows.yaml"));
   const windows = readFileSync(
     new URL("../../scripts/test-windows-clone-contract.ps1", import.meta.url),
@@ -299,7 +295,7 @@ test("Windows clone contract copies the shared complete schema v3 descriptor int
   expect(windows).not.toContain('schema_version: 3');
   expect(descriptor).toMatchObject({
     workspace: {
-      schema_version: 3,
+      schema_version: 4,
       id: "task13-windows",
       name: "Task 13 Windows",
       language: "en",

backend/test/workspace-registry.test.ts

@@ -15,7 +15,7 @@ import {
 import type { WorkspaceRegistryConfig } from "../src/workspaces/types.js";
 
 const validYaml = `workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: it
@@ -24,18 +24,6 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: psd-clinical
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 `;
 
 function withFilesystemEvidence(source: string, id = "psd-clinical"): string {
@@ -146,7 +134,7 @@ function legacyV1Yaml(source = validYaml): string {
     .replace("    model: qwen3-embedding:0.6b", "    model: nomic-embed-text-v2-moe")
     .replace("    dimensions: 1024", "    dimensions: 768")
     .replace("distance: cosine\n", "distance: cosine\n    supported_transports: [pgvector_direct]\n")
-    .replace("schema_version: 3", "schema_version: 1");
+    .replace("schema_version: 4", "schema_version: 1");
 }
 
 function legacyV2Yaml(source = validYaml): string {
@@ -158,7 +146,7 @@ function legacyV2Yaml(source = validYaml): string {
     .replace("    model: qwen3-embedding:0.6b", "    model: nomic-embed-text-v2-moe")
     .replace("    dimensions: 1024", "    dimensions: 768")
     .replace("distance: cosine\n", "distance: cosine\n    supported_transports: [pgvector_direct]\n")
-    .replace("schema_version: 3", "schema_version: 2");
+    .replace("schema_version: 4", "schema_version: 2");
 }
 
 const runFile = promisify(execFile);
@@ -197,7 +185,7 @@ async function fixture(workspaceSource = validYaml): Promise<{
   await git(source, ["init", "--initial-branch=main"]);
   await git(source, ["config", "user.name", "Workspace Registry Test"]);
   await git(source, ["config", "user.email", "workspace-registry@example.invalid"]);
-  const workspace = workspaceSource.includes("schema_version: 3")
+  const workspace = workspaceSource.includes("schema_version: 4")
     ? parseWorkspaceYaml(workspaceSource) : undefined;
   mkdirSync(join(source, "psd-clinical"), { recursive: true });
   writeFileSync(join(source, "thoth-workspaces.yaml"), catalogYaml([
@@ -256,7 +244,7 @@ async function multiWorkspaceFixture(workspaces: Record<string, string>): Promis
   await git(source, ["config", "user.email", "workspace-registry@example.invalid"]);
   const entries = [];
   for (const [id, workspaceSource] of Object.entries(workspaces)) {
-    const workspace = workspaceSource.includes("schema_version: 3") ? parseWorkspaceYaml(workspaceSource) : undefined;
+    const workspace = workspaceSource.includes("schema_version: 4") ? parseWorkspaceYaml(workspaceSource) : undefined;
     entries.push({ id, name: workspace.workspace.name, ...(workspace.workspace.description ? { description: workspace.workspace.description } : {}) });
     mkdirSync(join(source, id), { recursive: true });
     writeFileSync(join(source, id, "workspace.yaml"), workspaceSource);
@@ -788,7 +776,7 @@ test("normalizes historical operational state during offline fallback after rest
   expect(read.revision).not.toHaveProperty("state");
 });
 
-test("fails closed when a retained snapshot descriptor is not schema v3", async () => {
+test("fails closed when a retained snapshot descriptor is not schema v4", async () => {
   const remote = await fixture();
   const root = join(remote.root, "registry");
   await new WorkspaceRegistry(config(root, remote.remote)).bootstrap();
@@ -820,45 +808,6 @@ test("keeps the last valid snapshot when a pulled commit has invalid YAML", asyn
   });
 });
 
-test("rejects duplicate schema v3 collection ownership and keeps the previous active snapshot", async () => {
-  const v3Yaml = validYaml;
-  const remote = await multiWorkspaceFixture({
-    "psd-clinical": v3Yaml,
-    "research-clinical": v3Yaml
-      .replace("id: psd-clinical", "id: research-clinical")
-      .replace("name: Policlinico San Donato", "name: Research Clinical")
-      .replace("collection: psd-clinical", "collection: research-clinical"),
-  });
-  const registry = new WorkspaceRegistry(config(join(remote.root, "registry"), remote.remote));
-  await registry.bootstrap();
-
-  writeFileSync(
-    join(remote.source, "research-clinical", "workspace.yaml"),
-    v3Yaml
-      .replace("id: psd-clinical", "id: research-clinical")
-      .replace("name: Policlinico San Donato", "name: Research Clinical")
-      .replace("collection: psd-clinical", "collection: shared"),
-  );
-  writeFileSync(
-    join(remote.source, "psd-clinical", "workspace.yaml"),
-    v3Yaml.replace("collection: psd-clinical", "collection: shared"),
-  );
-  await git(remote.source, ["add", "-A"]);
-  await git(remote.source, ["commit", "-m", "Duplicate collection ownership"]);
-  await git(remote.source, ["push", "origin", "main"]);
-
-  await expect(registry.pull()).rejects.toMatchObject({
-    code: "workspace_invalid",
-    message: "Workspace repository content is invalid",
-  });
-  await expect(registry.read("psd-clinical")).resolves.toMatchObject({
-    revision: { commit: remote.initialCommit },
-  });
-  await expect(registry.read("research-clinical")).resolves.toMatchObject({
-    revision: { commit: remote.initialCommit },
-  });
-});
-
 test("retains a historical snapshot while a resumable manifest still references its revision", async () => {
   const remote = await fixture();
   const root = join(remote.root, "registry");

backend/test/workspace-runtime-config-lease.test.ts

@@ -66,7 +66,7 @@ workspaces: [{id: psd-clinical, name: Runtime Lease}]
 `);
   mkdirSync(join(source, "psd-clinical", "evidence"), { recursive: true });
   writeFileSync(join(source, "psd-clinical", "workspace.yaml"), `workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Runtime Lease
   language: en
@@ -75,18 +75,6 @@ dwh:
   database: analytics
   schema: mart
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: psd-clinical
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 evidence:
   source:
     type: filesystem

backend/test/workspace-runtime-handoff.test.ts

@@ -21,7 +21,7 @@ const thtBin = join(harnessDir, ".venv", "bin", "tht");
 const roots: string[] = [];
 
 const canonicalWorkspace = `workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Runtime handoff
   language: en
@@ -30,18 +30,6 @@ dwh:
   database: analytics
   schema: mart
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: psd-clinical
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 `;
 
 const filesystemWorkspace = `${canonicalWorkspace}evidence:
@@ -145,7 +133,7 @@ function runnerFor(f: Awaited<ReturnType<typeof fixture>>): ThtRunner {
   } as any);
 }
 
-test("real schema-v3 registry revision loads through ThtRunner and the harness contract", async () => {
+test("real schema-v4 registry revision loads through ThtRunner and the harness contract", async () => {
   const f = await fixture();
   const runner = runnerFor(f);
 

backend/test/workspace-runtime-renderer.test.ts

@@ -12,8 +12,8 @@ import {
 import { supportsSessionRuntime } from "../src/workspaces/bindings.js";
 import { parseWorkspaceYaml } from "../src/workspaces/schema.js";
 
-const workspaceV3 = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+const workspaceV4 = parseWorkspaceYaml(`workspace:
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: it
@@ -22,19 +22,6 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [postgres_direct, rest_api, ssh_tunnel]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: psd-clinical
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  default: zai/glm-5.2
-  allowed: [zai/glm-5.2]
 `);
 const paths: RuntimePaths = {
   sessions: "/data/workspaces/psd-clinical/sessions",
@@ -45,6 +32,7 @@ const paths: RuntimePaths = {
 const semanticRuntime: SemanticRuntimeConfig = {
   internalQdrantUrl: "http://qdrant:6333",
   internalEmbeddingUrl: "http://embedding:11434",
+  internalEmbeddingId: "ollama/qwen3-embedding:0.6b",
   internalEmbeddingModel: "qwen3-embedding:0.6b",
   internalEmbeddingDimensions: 1024,
 };
@@ -63,8 +51,8 @@ const directBindings: RuntimeBindings = {
   evidence: { missing: [], values: {} },
 };
 
-test("renders only the schema-v3 internal Qdrant and Ollama runtime shape", () => {
-  const rendered = parse(renderRuntimeConfig(workspaceV3, directBindings, paths, {
+test("derives the internal Qdrant and Ollama runtime shape from workspace v4 plus installation config", () => {
+  const rendered = parse(renderRuntimeConfig(workspaceV4, directBindings, paths, {
     workspaceId: "psd-clinical", workspaceRevision: "a".repeat(40),
   }, {}, semanticRuntime));
 
@@ -95,8 +83,8 @@ test("renders only the schema-v3 internal Qdrant and Ollama runtime shape", () =
   expect(rendered).not.toHaveProperty("vector_rest");
 });
 
-test("renders schema-v3 DWH REST without exposing secret contents", () => {
-  const rendered = parse(renderRuntimeConfig(workspaceV3, {
+test("renders workspace-v4 DWH REST without exposing secret contents", () => {
+  const rendered = parse(renderRuntimeConfig(workspaceV4, {
     dwh: {
       transport: "rest_api", missing: [], values: {
         THT_WS_PSD_CLINICAL_DWH_BASE_URL: "https://dwh.example.test",
@@ -152,7 +140,7 @@ function evidenceWorkspace(
 }
 
 const canonicalEvidenceWorkspace = `workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Runtime Evidence
   language: en
@@ -161,18 +149,6 @@ dwh:
   database: analytics
   schema: mart
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: psd-clinical
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 `;
 
 const evidenceRevision = "1".repeat(40);
@@ -374,7 +350,7 @@ test("renders static S3 Evidence with endpoint policy, limits, and file paths bu
 
 test("omits Evidence configuration and policy when the descriptor has no Evidence", () => {
   const rendered = parse(renderRuntimeConfig(
-    workspaceV3,
+    workspaceV4,
     directBindings,
     paths,
     evidenceContext,

backend/test/workspace-secret-requirements.test.ts

@@ -14,7 +14,7 @@ const roots: string[] = [];
 
 function workspace(extra = "") {
   return parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: en
@@ -23,10 +23,6 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [postgres_direct, rest_api, ssh_tunnel]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd-clinical, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
-llm_policy: { allowed: [zai/glm-5.2] }
 ${extra}`);
 }
 

backend/test/workspace-v4-migration.test.ts

@@ -0,0 +1,36 @@
+import { expect, test } from "vitest";
+import { migrateWorkspaceV3Yaml, parseWorkspaceYaml } from "../src/workspaces/schema.js";
+
+const legacy = `workspace:
+  schema_version: 3
+  id: abc
+  name: Example
+  language: en
+dwh:
+  engine: postgres
+  database: warehouse
+  schema: public
+  supported_transports: [postgres_direct]
+semantic_index:
+  vector_store: {engine: qdrant, collection: abc, dimensions: 1024, distance: cosine}
+  embedding: {provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024}
+llm_policy:
+  default: zai/glm-5.3
+  allowed: [zai/glm-5.3]
+`;
+
+test("strict workspace v4 rejects model-bearing v3 descriptors", () => {
+  expect(() => parseWorkspaceYaml(legacy)).toThrow();
+});
+
+test("v3 to v4 migration removes only model/vector policy and bumps the version", () => {
+  const migrated = migrateWorkspaceV3Yaml(legacy);
+  const workspace = parseWorkspaceYaml(migrated);
+
+  expect(workspace.workspace).toMatchObject({ schema_version: 4, id: "abc" });
+  expect(migrated).not.toMatch(/semantic_index|llm_policy/);
+  expect(workspace.dwh).toEqual({
+    engine: "postgres", database: "warehouse", schema: "public",
+    supported_transports: ["postgres_direct"],
+  });
+});

backend/test/workspaces-bindings.test.ts

@@ -9,8 +9,8 @@ import {
 } from "../src/workspaces/bindings.js";
 import { parseWorkspaceYaml } from "../src/workspaces/schema.js";
 
-const workspaceV3 = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+const workspaceV4 = parseWorkspaceYaml(`workspace:
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: it
@@ -19,10 +19,6 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [postgres_direct, rest_api, ssh_tunnel]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd-clinical, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
-llm_policy: { allowed: [zai/glm-5.2] }
 `);
 const temporaryRoots: string[] = [];
 
@@ -40,9 +36,9 @@ function secretPath(name: string): { root: string; path: string } {
   return { root: secrets, path };
 }
 
-test("resolves schema-v3 direct DWH bindings from the stable namespace", () => {
+test("resolves workspace-v4 direct DWH bindings from the stable namespace", () => {
   const password = secretPath("dwh-password");
-  const result = resolveBinding(workspaceV3, "DWH", {
+  const result = resolveBinding(workspaceV4, "DWH", {
     THT_WS_PSD_CLINICAL_DWH_TRANSPORT: "postgres_direct",
     THT_WS_PSD_CLINICAL_DWH_HOST: "dwh.internal",
     THT_WS_PSD_CLINICAL_DWH_PORT: "5432",
@@ -61,14 +57,14 @@ test("resolves schema-v3 direct DWH bindings from the stable namespace", () => {
   });
 });
 
-test("requires schema-v3 REST credentials unless the DWH diagnostic declares auth none", () => {
-  expect(resolveBinding(workspaceV3, "DWH", {
+test("requires workspace-v4 REST credentials unless the DWH diagnostic declares auth none", () => {
+  expect(resolveBinding(workspaceV4, "DWH", {
     THT_WS_PSD_CLINICAL_DWH_TRANSPORT: "rest_api",
     THT_WS_PSD_CLINICAL_DWH_BASE_URL: "https://dwh.example.test",
   }, []).missing).toContain("THT_WS_PSD_CLINICAL_DWH_API_KEY_FILE");
 
   const noAuth = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: No auth
   language: en
@@ -77,16 +73,12 @@ dwh:
   database: postgres
   schema: public
   supported_transports: [rest_api]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd-clinical, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
 diagnostics:
   dwh_rest:
     method: GET
     path: /health
     auth: none
     response: { database: database, schema: schema }
-llm_policy: { allowed: [zai/glm-5.2] }
 `);
   expect(resolveBinding(noAuth, "DWH", {
     THT_WS_PSD_CLINICAL_DWH_TRANSPORT: "rest_api",
@@ -98,7 +90,7 @@ test("rejects unsupported transports and secret paths outside configured roots",
   const outside = secretPath("outside-password");
   const allowed = secretPath("allowed-password");
   const directOnly = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Direct only
   language: en
@@ -107,15 +99,11 @@ dwh:
   database: postgres
   schema: public
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd-clinical, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
-llm_policy: { allowed: [zai/glm-5.2] }
 `);
   expect(resolveBinding(directOnly, "DWH", {
     THT_WS_PSD_CLINICAL_DWH_TRANSPORT: "rest_api",
   }, []).missing).toContain("THT_WS_PSD_CLINICAL_DWH_TRANSPORT");
-  const result = resolveBinding(workspaceV3, "DWH", {
+  const result = resolveBinding(workspaceV4, "DWH", {
     THT_WS_PSD_CLINICAL_DWH_TRANSPORT: "postgres_direct",
     THT_WS_PSD_CLINICAL_DWH_HOST: "dwh.internal",
     THT_WS_PSD_CLINICAL_DWH_PORT: "5432",
@@ -128,7 +116,7 @@ llm_policy: { allowed: [zai/glm-5.2] }
 
 test("runtime bindings contain only DWH and Evidence roles", () => {
   const password = secretPath("dwh-password");
-  const bindings = resolveRuntimeBindings(workspaceV3, {
+  const bindings = resolveRuntimeBindings(workspaceV4, {
     THT_WS_PSD_CLINICAL_DWH_TRANSPORT: "postgres_direct",
     THT_WS_PSD_CLINICAL_DWH_HOST: "dwh.internal",
     THT_WS_PSD_CLINICAL_DWH_PORT: "5432",
@@ -143,7 +131,7 @@ test("runtime bindings contain only DWH and Evidence roles", () => {
 
 function withEvidence(source: Record<string, unknown>) {
   return parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: it
@@ -152,10 +140,6 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd-clinical, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
-llm_policy: { allowed: [zai/glm-5.2] }
 evidence:
   source: ${JSON.stringify(source)}
 `);
@@ -260,7 +244,7 @@ test("rejects relative, missing, directory, unreadable, and escaping symlink Evi
 });
 
 test("includes Evidence binding completeness in session runtime support without changing v3 compatibility", () => {
-  const unsigned = resolveRuntimeBindings(workspaceV3, {}, ["/run/secrets"]);
+  const unsigned = resolveRuntimeBindings(workspaceV4, {}, ["/run/secrets"]);
   expect(unsigned.evidence).toEqual({ values: {}, missing: [] });
   expect(supportsSessionRuntime(unsigned)).toBe(true);
 

backend/test/workspaces-catalog.test.ts

@@ -7,7 +7,7 @@ import {
 } from "../src/workspaces/catalog.js";
 
 const descriptor = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd
   name: Policlinico San Donato
   description: Clinical warehouse
@@ -17,10 +17,6 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [rest_api]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
-llm_policy: { allowed: [zai/glm-5.2] }
 `);
 
 test("parses the strict ordered root catalog", () => {

backend/test/workspaces-contracts.test.ts

@@ -5,8 +5,8 @@ import { join } from "node:path";
 import { buildInstallationContract, renderWorkspaceDocs } from "../src/workspaces/contracts.js";
 import { type CanonicalWorkspace, parseWorkspaceYaml } from "../src/workspaces/schema.js";
 
-const workspaceV3 = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+const workspaceV4 = parseWorkspaceYaml(`workspace:
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: it
@@ -15,17 +15,12 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [postgres_direct, rest_api, ssh_tunnel]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd-clinical, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
-llm_policy:
-  allowed: [zai/glm-5.2]
 `);
 
-test("schema-v3 installation contracts expose only DWH bindings and no semantic variables", () => {
-  const contract = buildInstallationContract(workspaceV3);
+test("workspace-v4 installation contracts expose only DWH bindings and no semantic variables", () => {
+  const contract = buildInstallationContract(workspaceV4);
   const names = contract.variables.map((variable) => variable.name);
-  const docs = renderWorkspaceDocs(workspaceV3);
+  const docs = renderWorkspaceDocs(workspaceV4);
 
   expect(contract.workspaceId).toBe("psd-clinical");
   expect(contract.namespace).toBe("PSD_CLINICAL");
@@ -54,22 +49,22 @@ test.each([
 
 test("validates public contract and documentation inputs at runtime", () => {
   const unsafeWorkspace = {
-    ...workspaceV3,
-    workspace: { ...workspaceV3.workspace, id: "psd\nclinical" },
+    ...workspaceV4,
+    workspace: { ...workspaceV4.workspace, id: "psd\nclinical" },
   } as CanonicalWorkspace;
 
   expect(() => buildInstallationContract(unsafeWorkspace)).toThrow(/id/i);
   expect(() => renderWorkspaceDocs(unsafeWorkspace)).toThrow(/id/i);
 });
 
-test("v3 installation contract omits external vector and embedding bindings", () => {
-  const contract = buildInstallationContract(workspaceV3);
+test("v4 installation contract omits external vector and embedding bindings", () => {
+  const contract = buildInstallationContract(workspaceV4);
   const names = contract.variables.map((variable) => variable.name);
 
   expect(names).toContain("THT_WS_PSD_CLINICAL_DWH_TRANSPORT");
   expect(names.some((name) => name.includes("_VECTOR_"))).toBe(false);
   expect(names.some((name) => name.includes("_EMBEDDING_"))).toBe(false);
-  expect(renderWorkspaceDocs(workspaceV3).markdown).not.toContain("Embedding service");
+  expect(renderWorkspaceDocs(workspaceV4).markdown).not.toContain("Embedding service");
 });
 
 
@@ -114,7 +109,7 @@ test.each([
 
 function renderWorkspaceWithoutEvidence(): string {
   return `workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: it
@@ -123,10 +118,6 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd-clinical, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
-llm_policy: { allowed: [zai/glm-5.2] }
 `;
 }
 

backend/test/workspaces-diagnostics.test.ts

@@ -12,7 +12,7 @@ import type { RuntimeBindings } from "../src/workspaces/runtime-renderer.js";
 import { parseWorkspaceYaml, resolveDiagnosticUrl } from "../src/workspaces/schema.js";
 
 const workspace = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: it
@@ -22,18 +22,6 @@ dwh:
   schema: datawarehouse
   timeout_ms: 8000
   supported_transports: [postgres_direct, rest_api, ssh_tunnel]
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: psd-clinical
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  allowed: [zai/glm-5.2]
 `);
 
 const bindings: RuntimeBindings = {
@@ -78,7 +66,7 @@ afterEach(() => {
   vi.restoreAllMocks();
 });
 
-test("diagnoses schema-v3 DWH, internal Qdrant, and internal Ollama without semantic bindings", async () => {
+test("diagnoses workspace-v4 DWH plus installation-derived Qdrant and Ollama", async () => {
   const adapters = successfulAdapters();
   const result = await diagnose(adapters)(workspace, bindings, { writeProbe: false });
 
@@ -139,7 +127,7 @@ test("reports only sanitized DWH and Evidence binding names before network diagn
   expect(adapters.inspectQdrant).not.toHaveBeenCalled();
 });
 
-test("keeps schema-v3 DWH SSH diagnostic-only and runtime-inactive", async () => {
+test("keeps workspace-v4 DWH SSH diagnostic-only and runtime-inactive", async () => {
   const adapters = successfulAdapters();
   const result = await diagnose(adapters)(workspace, {
     ...bindings,
@@ -152,9 +140,9 @@ test("keeps schema-v3 DWH SSH diagnostic-only and runtime-inactive", async () =>
   expect(adapters.probeConnector).not.toHaveBeenCalled();
 });
 
-test("uses the schema-v3 declared DWH REST diagnostic and auth policy", async () => {
+test("uses the workspace-v4 declared DWH REST diagnostic and auth policy", async () => {
   const restWorkspace = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: REST workspace
   language: en
@@ -163,16 +151,12 @@ dwh:
   database: warehouse
   schema: datawarehouse
   supported_transports: [rest_api]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd-clinical, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
 diagnostics:
   dwh_rest:
     method: POST
     path: /rpc/ping
     auth: bearer
     response: { database: database, schema: schema }
-llm_policy: { allowed: [zai/glm-5.2] }
 `);
   const adapters = successfulAdapters();
   const result = await diagnose(adapters)(restWorkspace, {
@@ -423,7 +407,7 @@ test("uses a REST secret only as a header and redacts it from failed diagnostics
   const canary = "CANARY-REST-AUTH-SECRET";
   await writeFile(credentialFile, canary);
   const restDescriptor = parseWorkspaceYaml(`workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: REST auth
   language: en
@@ -432,16 +416,12 @@ dwh:
   database: warehouse
   schema: datawarehouse
   supported_transports: [rest_api]
-semantic_index:
-  vector_store: { engine: qdrant, collection: psd-clinical, dimensions: 1024, distance: cosine }
-  embedding: { provider: ollama_internal, model: qwen3-embedding:0.6b, dimensions: 1024 }
 diagnostics:
   dwh_rest:
     method: GET
     path: /health
     auth: bearer
     response: { database: database, schema: schema }
-llm_policy: { allowed: [zai/glm-5.2] }
 `);
   const fetchMock = vi.fn()
     .mockResolvedValueOnce(new Response("upstream CANARY-REST-AUTH-SECRET", { status: 503 }))

backend/test/workspaces-git-annotations.test.ts

@@ -53,7 +53,7 @@ async function makeRepo(id: string, annotations: string | Buffer | "dir" | "syml
   writeFileSync(join(source, "thoth-workspaces.yaml"),
     `schema_version: 1\nworkspaces: [{id: ${id}, name: Workspace}]\n`);
   mkdirSync(join(source, id, "schema"), { recursive: true });
-  writeFileSync(join(source, id, "workspace.yaml"), `workspace:\n  schema_version: 3\n  id: ${id}\n`);
+  writeFileSync(join(source, id, "workspace.yaml"), `workspace:\n  schema_version: 4\n  id: ${id}\n`);
   const annotationsPath = join(source, id, "schema", "annotations.yaml");
   if (annotations === "dir") {
     mkdirSync(annotationsPath, { recursive: true });

backend/test/workspaces-git-evidence.test.ts

@@ -47,7 +47,7 @@ async function fixture(layout: EvidenceLayout): Promise<{ root: string; remote:
   await git(source, ["config", "user.email", "evidence@example.invalid"]);
   writeFileSync(join(source, "thoth-workspaces.yaml"), "schema_version: 1\nworkspaces: [{id: research, name: Research}]\n");
   mkdirSync(join(source, "research"), { recursive: true });
-  writeFileSync(join(source, "research", "workspace.yaml"), "workspace:\n  schema_version: 3\n  id: research\n");
+  writeFileSync(join(source, "research", "workspace.yaml"), "workspace:\n  schema_version: 4\n  id: research\n");
   const evidence = join(source, "research", "evidence");
   if (layout === "tree") {
     mkdirSync(join(evidence, "nested"), { recursive: true });

backend/test/workspaces-git-repository.test.ts

@@ -12,7 +12,7 @@ import {
 import type { WorkspaceRegistryConfig } from "../src/workspaces/types.js";
 
 const validYaml = `workspace:
-  schema_version: 2
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   language: it
@@ -21,21 +21,6 @@ dwh:
   database: postgres
   schema: datawarehouse
   supported_transports: [postgres_direct]
-semantic_index:
-  vector_store:
-    engine: pgvector
-    database: postgres
-    schema: vectors
-    collection: clinical_documents
-    dimensions: 768
-    distance: cosine
-    supported_transports: [pgvector_direct]
-  embedding:
-    provider: ollama_compatible
-    model: nomic-embed-text-v2-moe
-    dimensions: 768
-llm_policy:
-  allowed: [zai/glm-5.2]
 `;
 
 const runFile = promisify(execFile);

backend/test/workspaces-runtime-v4-boundaries.test.ts

@@ -13,20 +13,11 @@ import {
 import { renderRuntimeConfig, type RuntimeBindings } from "../src/workspaces/runtime-renderer.js";
 
 const unsupportedWorkspace = {
-  workspace: { schema_version: 2, id: "legacy-workspace", name: "Legacy", language: "en" },
+  workspace: { schema_version: 3, id: "legacy-workspace", name: "Legacy", language: "en" },
   dwh: {
     engine: "postgres", database: "warehouse", schema: "public",
     supported_transports: ["postgres_direct"],
   },
-  semantic_index: {
-    vector_store: {
-      engine: "pgvector", database: "warehouse", schema: "vectors",
-      collection: "documents", dimensions: 768, distance: "cosine",
-      supported_transports: ["pgvector_direct"],
-    },
-    embedding: { provider: "ollama_compatible", model: "legacy", dimensions: 768 },
-  },
-  llm_policy: { allowed: ["zai/glm-5.2"] },
 };
 
 const bindings: RuntimeBindings = {
@@ -40,31 +31,31 @@ const adapters: DiagnosticAdapters = {
   probeEmbedding: vi.fn(),
 };
 
-test("renderer rejects callers that bypass the schema-v3 type contract", () => {
+test("renderer rejects callers that bypass the schema-v4 type contract", () => {
   expect(() => renderRuntimeConfig(unsupportedWorkspace as never, bindings, {
     sessions: "/data/sessions", artifacts: "/data/artifacts", indexes: "/data/indexes",
-  })).toThrow("Runtime renderer supports only workspace schema version 3");
+  })).toThrow("Runtime renderer supports only workspace schema version 4");
 });
 
-test("installation contract rejects callers that bypass the schema-v3 type contract", () => {
+test("installation contract rejects callers that bypass the schema-v4 type contract", () => {
   expect(() => buildInstallationContract(unsupportedWorkspace as never))
-    .toThrow("Installation contract supports only workspace schema version 3");
+    .toThrow("Installation contract supports only workspace schema version 4");
 });
 
-test("binding entry points reject callers that bypass the schema-v3 type contract", () => {
+test("binding entry points reject callers that bypass the schema-v4 type contract", () => {
   expect(() => resolveBinding(unsupportedWorkspace as never, "DWH", {}, []))
-    .toThrow("Workspace bindings support only workspace schema version 3");
+    .toThrow("Workspace bindings support only workspace schema version 4");
   expect(() => resolveEvidenceBinding(unsupportedWorkspace as never, {}, []))
-    .toThrow("Workspace bindings support only workspace schema version 3");
+    .toThrow("Workspace bindings support only workspace schema version 4");
   expect(() => resolveRuntimeBindings(unsupportedWorkspace as never, {}, []))
-    .toThrow("Workspace bindings support only workspace schema version 3");
+    .toThrow("Workspace bindings support only workspace schema version 4");
 });
 
-test("diagnoser factories reject callers that bypass the schema-v3 type contract", async () => {
+test("diagnoser factories reject callers that bypass the schema-v4 type contract", async () => {
   await expect(createWorkspaceDiagnoser(adapters)(unsupportedWorkspace as never, bindings, {
     writeProbe: false,
-  })).rejects.toThrow("Workspace diagnoser supports only workspace schema version 3");
+  })).rejects.toThrow("Workspace diagnoser supports only workspace schema version 4");
   await expect(createProductionWorkspaceDiagnoser(5_000, adapters)(
     unsupportedWorkspace as never, bindings, { writeProbe: false },
-  )).rejects.toThrow("Workspace diagnoser supports only workspace schema version 3");
+  )).rejects.toThrow("Workspace diagnoser supports only workspace schema version 4");
 });

backend/test/workspaces-schema.test.ts

@@ -10,7 +10,7 @@ import {
 } from "../src/workspaces/schema.js";
 
 export const validYaml = `workspace:
-  schema_version: 3
+  schema_version: 4
   id: psd-clinical
   name: Policlinico San Donato
   description: Clinical data warehouse workspace
@@ -25,33 +25,8 @@ dwh:
     - postgres_direct
     - rest_api
     - ssh_tunnel
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: psd-clinical
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-llm_policy:
-  default: zai/glm-5.2
-  allowed:
-    - zai/glm-5.2
-    - openai/gpt-5
 `;
 
-test("rejects a workspace whose embedding dimensions differ from its collection", () => {
-  expect(() => parseWorkspaceYaml(validYaml.replace("dimensions: 1024", "dimensions: 1536")))
-    .toThrow(/dimensions/i);
-});
-
-test("rejects an LLM default outside its allowlist", () => {
-  expect(() => parseWorkspaceYaml(validYaml.replace("- zai/glm-5.2", "- openai/gpt-5")))
-    .toThrow(/allowlist/i);
-});
-
 test("rejects unknown keys and invalid immutable IDs", () => {
   expect(() => parseWorkspaceYaml(validYaml.replace("  language: it", "  language: it\n  label: PSD")))
     .toThrow(/unrecognized key/i);
@@ -74,94 +49,34 @@ test("accepts optional connection ports and timeouts but rejects unsafe values",
     .toThrow(/port/i);
   expect(() => parseWorkspaceYaml(validYaml.replace("timeout_ms: 5000", "timeout_ms: 0")))
     .toThrow(/timeout/i);
-  expect(() => parseWorkspaceYaml(validYaml.replace("dimensions: 1024", "dimensions: 2048")))
-    .toThrow(/1024|dimensions/i);
 });
 
-test("accepts only the schema v3 internal qdrant semantic shape", () => {
+test("accepts a model-free schema v4 workspace", () => {
   expect(parseWorkspaceYaml(validYaml)).toMatchObject({
-    workspace: { schema_version: 3, id: "psd-clinical" },
-    semantic_index: {
-      vector_store: {
-        engine: "qdrant",
-        collection: "psd-clinical",
-        dimensions: 1024,
-        distance: "cosine",
-      },
-      embedding: {
-        provider: "ollama_internal",
-        model: "qwen3-embedding:0.6b",
-        dimensions: 1024,
-      },
-    },
+    workspace: { schema_version: 4, id: "psd-clinical" },
+    dwh: { database: "postgres", schema: "datawarehouse" },
   });
 });
 
-test("committed example descriptors parse as exact schema v3 workspaces", () => {
+test("committed example descriptors parse as exact schema v4 workspaces", () => {
   const example = readFileSync(resolve(process.cwd(), "../deploy/workspaces/example.yaml"), "utf8");
   const psdExample = readFileSync(resolve(process.cwd(), "../deploy/workspaces/psd.yaml.example"), "utf8");
 
   expect(() => parseWorkspaceYaml(example)).not.toThrow();
   expect(() => parseWorkspaceYaml(psdExample)).not.toThrow();
   expect(parseWorkspaceYaml(example)).toMatchObject({
-    workspace: { schema_version: 3 },
-    semantic_index: {
-      vector_store: { engine: "qdrant", distance: "cosine", dimensions: 1024 },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
+    workspace: { schema_version: 4 },
   });
   expect(parseWorkspaceYaml(psdExample)).toMatchObject({
-    workspace: { schema_version: 3 },
-    semantic_index: {
-      vector_store: { engine: "qdrant", distance: "cosine", dimensions: 1024 },
-      embedding: { provider: "ollama_internal", model: "qwen3-embedding:0.6b", dimensions: 1024 },
-    },
+    workspace: { schema_version: 4 },
   });
 });
 
-test("rejects pgvector semantic stores in schema v3", () => {
-  expect(() => parseWorkspaceYaml(validYaml.replace("engine: qdrant", "engine: pgvector")))
-    .toThrow(/qdrant|pgvector/i);
-});
-
-test("rejects supported_transports inside schema v3 semantic identity", () => {
-  const withTransport = validYaml.replace(
-    "    distance: cosine\n",
-    "    distance: cosine\n    supported_transports:\n      - rest_api\n",
-  );
-
-  expect(() => parseWorkspaceYaml(withTransport)).toThrow(/unrecognized key|supported_transports/i);
-});
-
-test("rejects external embedding providers in schema v3", () => {
-  expect(() => parseWorkspaceYaml(validYaml.replace("provider: ollama_internal", "provider: openai_compatible")))
-    .toThrow(/ollama_internal|provider/i);
-});
-
-test("rejects non-cosine distance in schema v3", () => {
-  expect(() => parseWorkspaceYaml(validYaml.replace("distance: cosine", "distance: l2")))
-    .toThrow(/cosine|distance/i);
-});
-
-test("rejects unknown fields in schema v3 semantic identity", () => {
-  const withUnknownField = validYaml.replace(
-    "    collection: psd-clinical\n",
-    "    collection: psd-clinical\n    namespace: psd\n",
-  );
-
-  expect(() => parseWorkspaceYaml(withUnknownField)).toThrow(/unrecognized key/i);
-});
-
-test("rejects legacy semantic connector fields and diagnostics in schema v3", () => {
-  expect(() => parseWorkspaceYaml(validYaml.replace(
-    "    collection: psd-clinical\n",
-    "    collection: psd-clinical\n    database: postgres\n",
-  ))).toThrow(/unrecognized key|database/i);
-
-  expect(() => parseWorkspaceYaml(validYaml.replace(
-    "llm_policy:\n",
-    "diagnostics:\n  vector_rest:\n    metadata:\n      method: GET\n      path: /metadata\n      auth: bearer\n      response:\n        collection: collection\n        dimensions: dimensions\n        distance: distance\nllm_policy:\n",
-  ))).toThrow(/unrecognized key|vector_rest/i);
+test("rejects installation-owned model and vector fields", () => {
+  expect(() => parseWorkspaceYaml(`${validYaml}llm_policy:\n  allowed: [zai/glm-5.3]\n`))
+    .toThrow(/unrecognized key|llm_policy/i);
+  expect(() => parseWorkspaceYaml(`${validYaml}semantic_index: {}\n`))
+    .toThrow(/unrecognized key|semantic_index/i);
 });
 
 test.each([
@@ -222,8 +137,8 @@ llm_policy:
     - zai/glm-5.2
 `],
 ])("rejects schema %s descriptors at parser and object-validator boundaries", (_version, yaml) => {
-  expect(() => parseWorkspaceYaml(yaml)).toThrow(/schema_version|invalid literal|3/i);
-  expect(() => validateWorkspaceDescriptor(parse(yaml))).toThrow(/schema_version|invalid literal|3/i);
+  expect(() => parseWorkspaceYaml(yaml)).toThrow(/schema_version|invalid literal|4/i);
+  expect(() => validateWorkspaceDescriptor(parse(yaml))).toThrow(/schema_version|invalid literal|4/i);
 });
 
 test("does not expose the redundant canonical validator or v1 migration", () => {
@@ -253,9 +168,8 @@ test("rejects REST diagnostic declarations without their matching connector tran
     response:
       database: database
       schema: schema
-llm_policy:
 `;
-  const declared = validYaml.replace("llm_policy:\n", diagnostics);
+  const declared = `${validYaml}${diagnostics}`;
 
   expect(() => parseWorkspaceYaml(declared.replace("    - rest_api\n", ""))).toThrow(/dwh_rest/i);
 });
@@ -462,7 +376,7 @@ test.each(["curated/**/*.yaml", "curated/**"])(
   },
 );
 
-test("keeps evidence optional on schema v3", () => {
+test("keeps evidence optional on schema v4", () => {
   expect(validateWorkspaceDescriptor(validWorkspaceObject())).not.toHaveProperty("evidence");
 });
 
@@ -471,7 +385,7 @@ test("serializes defaulted evidence canonically and parses it without loss", ()
     type: "filesystem",
     uri: "psd-clinical/evidence",
   }));
-  if (canonical.workspace.schema_version !== 3) throw new Error("expected schema v3");
+  if (canonical.workspace.schema_version !== 4) throw new Error("expected schema v4");
 
   expect(parseWorkspaceYaml(serializeWorkspaceYaml(canonical))).toEqual(canonical);
 });

backend/test/workspaces/evidence/materialization.test.ts

@@ -46,7 +46,7 @@ async function fixture(): Promise<{ root: string; remote: string; commit: string
   await git(source, ["config", "user.email", "evidence-materializer@example.invalid"]);
   writeFileSync(join(source, "thoth-workspaces.yaml"), "schema_version: 1\nworkspaces: [{id: research, name: Research}]\n");
   mkdirSync(join(source, "research", "evidence", "nested"), { recursive: true });
-  writeFileSync(join(source, "research", "workspace.yaml"), "workspace:\n  schema_version: 3\n  id: research\n");
+  writeFileSync(join(source, "research", "workspace.yaml"), "workspace:\n  schema_version: 4\n  id: research\n");
   writeFileSync(join(source, "research", "evidence", "guide.md"), "# guide\n");
   writeFileSync(join(source, "research", "evidence", "nested", "deep.md"), "# deep\n");
   await git(source, ["add", "-A"]);
@@ -102,7 +102,7 @@ test("refuses symlink-containing trees and bound violations without publishing",
   await git(source, ["config", "user.email", "e@e.invalid"]);
   writeFileSync(join(source, "thoth-workspaces.yaml"), "schema_version: 1\nworkspaces: [{id: research, name: Research}]\n");
   mkdirSync(join(source, "research", "evidence"), { recursive: true });
-  writeFileSync(join(source, "research", "workspace.yaml"), "workspace:\n  schema_version: 3\n  id: research\n");
+  writeFileSync(join(source, "research", "workspace.yaml"), "workspace:\n  schema_version: 4\n  id: research\n");
   writeFileSync(join(source, "research", "outside.md"), "# outside\n");
   symlinkSync("../outside.md", join(source, "research", "evidence", "link.md"));
   await git(source, ["add", "-A"]);

compose.yaml

@@ -36,15 +36,11 @@ services:
       THT_LLM_URL: ${THT_LLM_URL:-}
       THT_INTERNAL_QDRANT_URL: http://qdrant:6333
       THT_INTERNAL_EMBEDDING_URL: http://embedding:11434
-      THT_INTERNAL_EMBEDDING_MODEL: qwen3-embedding:0.6b
-      THT_INTERNAL_EMBEDDING_DIMENSIONS: "1024"
       MAX_PI_PROCESSES: ${MAX_PI_PROCESSES:-4}
     volumes:
       - settings:/data/settings
       - pi-state:/home/thoth/.pi
       - ${PI_AUTH_FILE:?set PI_AUTH_FILE}:/home/thoth/.pi/agent/auth.json:ro
-      - ./deploy/pi/models.json:/home/thoth/.pi/agent/models.json:ro
-      - ./deploy/pi/settings.json:/home/thoth/.pi/agent/settings.json:ro
       - workspace-registry:/data/workspace-registry
       - workspace-secrets:/data/workspace-secrets
       - sessions:/data/sessions
@@ -140,8 +136,6 @@ services:
       THT_LLM_URL: ${THT_LLM_URL:-}
       THT_INTERNAL_QDRANT_URL: http://qdrant:6333
       THT_INTERNAL_EMBEDDING_URL: http://embedding:11434
-      THT_INTERNAL_EMBEDDING_MODEL: qwen3-embedding:0.6b
-      THT_INTERNAL_EMBEDDING_DIMENSIONS: "1024"
       HOME: /tmp/thoth
       AWS_ACCESS_KEY_ID: ""
       AWS_SECRET_ACCESS_KEY: ""
@@ -243,7 +237,6 @@ services:
     entrypoint: ["/usr/bin/bash", "/opt/thoth/embedding-model-init.sh"]
     environment:
       OLLAMA_BASE_URL: http://embedding:11434
-      OLLAMA_MODEL: qwen3-embedding:0.6b
       OLLAMA_WAIT_TIMEOUT_SEC: "180"
     volumes:
       - embedding-models:/root/.ollama

deploy/compose.server.yaml

@@ -21,14 +21,6 @@ services:
         source: ${PI_AUTH_FILE:?set PI_AUTH_FILE}
         target: /home/thoth/.pi/agent/auth.json
         read_only: true
-      - type: bind
-        source: ./deploy/pi/models.json
-        target: /home/thoth/.pi/agent/models.json
-        read_only: true
-      - type: bind
-        source: ./deploy/pi/settings.json
-        target: /home/thoth/.pi/agent/settings.json
-        read_only: true
       - type: bind
         source: ${THT_WORKSPACE_REGISTRY_ROOT:?set THT_WORKSPACE_REGISTRY_ROOT}
         target: /data/workspace-registry

deploy/pi/models.json

@@ -1,46 +0,0 @@
-{
-  "providers": {
-    "zai": {
-      "baseUrl": "https://api.z.ai/api/coding/paas/v4",
-      "api": "openai-completions",
-      "apiKey": "$ZAI_API_KEY",
-      "models": [
-        {
-          "id": "glm-5.3",
-          "name": "GLM-5.3",
-          "reasoning": true,
-          "contextWindow": 200000,
-          "maxTokens": 131072
-        }
-      ]
-    },
-    "local-qwen": {
-      "name": "Local Qwen",
-      "baseUrl": "https://ml-aritmolab.policlinicosandonato.it/v1",
-      "api": "openai-completions",
-      "apiKey": "local",
-      "models": [
-        {
-          "id": "qwen3.6-35b-a3b",
-          "name": "Qwen3.6 35B A3B",
-          "reasoning": false,
-          "input": ["text"],
-          "cost": {
-            "input": 0,
-            "output": 0,
-            "cacheRead": 0,
-            "cacheWrite": 0
-          },
-          "contextWindow": 131072,
-          "maxTokens": 16384,
-          "compat": {
-            "supportsDeveloperRole": false,
-            "supportsReasoningEffort": false,
-            "supportsStore": false,
-            "maxTokensField": "max_tokens"
-          }
-        }
-      ]
-    }
-  }
-}

deploy/pi/settings.json

@@ -1,9 +0,0 @@
-{
-  "defaultProjectTrust": "always",
-  "enabledModels": [
-    "zai/glm-5.3",
-    "deepseek/deepseek-v4-flash",
-    "deepseek/deepseek-v4-pro",
-    "local-qwen/qwen3.6-35b-a3b"
-  ]
-}

deploy/psd/operator.env.example

@@ -14,9 +14,7 @@ THT_AUTH_CONFIG_ROOT=<abs>/deploy/psd/auth
 # DWH and Evidence credentials are entered later in Workspace management and stored encrypted
 # by the backend. They do not depend on host filesystem paths.
 
-# Pi (LLM)
-PI_PROVIDER=zai
-PI_MODEL=glm-5.3
+# Pi runtime preference; provider/model defaults live only in installation modelCatalog.
 PI_THINKING=medium
 
 # App defaults

deploy/psd/thothii-installation.yaml.example

@@ -1,6 +1,6 @@
-# Esempio soltanto: `tht setup` genera deploy/<installation-id>/thothii-installation.yaml.
-# Sostituisci i path assoluti se usi questo riferimento per una configurazione avanzata.
-# Seleziona UN solo override Git (https o ssh).
+# Example only: `tht setup` generates deploy/<installation-id>/thothii-installation.yaml.
+# Replace every absolute path before using this as an advanced reference.
+schemaVersion: 2
 profile: local
 projectDirectory: "<abs>/projects/ThothII"
 envFile: "<abs>/projects/ThothII/deploy/psd/operator.env"
@@ -8,38 +8,67 @@ workspaceRepository:
   remote: git@github.com:mptyl/tht-workspace-psd.git
   branch: main
   access: ssh
-metadataGeneration:
-  default: glm-53
-  models:
-    - id: deepseek-v4-pro
-      label: DeepSeek V4 Pro
-      litellm:
-        provider: deepseek
-        model: deepseek-v4-pro
-      apiKeyEnv: DEEPSEEK_API_KEY
-    - id: deepseek-v4-flash
-      label: DeepSeek V4 Flash
-      litellm:
-        provider: deepseek
-        model: deepseek-v4-flash
-      apiKeyEnv: DEEPSEEK_API_KEY
-    - id: glm-53
-      label: GLM 5.3
-      litellm:
-        provider: openai
-        model: glm-5.3
-        endpoint:
-          baseUrl: https://api.z.ai/api/coding/paas/v4
-      apiKeyEnv: ZAI_API_KEY
-    - id: qwen-36
-      label: AritmoLab Qwen 3.6 35B A3B
-      litellm:
-        provider: openai
-        model: qwen3.6-35b-a3b
-        disableThinking: true
-        endpoint:
-          baseUrl: https://ml-aritmolab.policlinicosandonato.it/v1
-# Qwen omette apiKeyEnv: l'endpoint VPN non autentica le richieste.
+modelCatalog:
+  defaults:
+    session: zai/glm-5.3
+    metadataGeneration: zai/glm-5.3
+  embedding:
+    id: ollama/qwen3-embedding:0.6b
+    dimensions: 1024
+  providers:
+    deepseek:
+      authentication:
+        mode: pi_auth
+      session:
+        mode: pi_builtin
+      models:
+        deepseek-v4-pro:
+          session: {}
+        deepseek-v4-flash:
+          session: {}
+    zai:
+      endpoint:
+        baseUrl: https://api.z.ai/api/coding/paas/v4
+      authentication:
+        mode: secret_env
+        apiKeyEnv: ZAI_API_KEY
+      session:
+        mode: openai_compatible
+      metadataGeneration:
+        litellmProvider: openai
+      models:
+        glm-5.3:
+          label: GLM 5.3
+          session:
+            reasoning: true
+            contextWindow: 200000
+            maxTokens: 131072
+          metadataGeneration: {}
+    local-qwen:
+      endpoint:
+        baseUrl: https://ml-aritmolab.policlinicosandonato.it/v1
+      authentication:
+        mode: none
+      session:
+        mode: openai_compatible
+      metadataGeneration:
+        litellmProvider: openai
+      models:
+        qwen3.6-35b-a3b:
+          label: AritmoLab Qwen 3.6 35B A3B
+          session:
+            reasoning: false
+            input: [text]
+            cost: {input: 0, output: 0, cacheRead: 0, cacheWrite: 0}
+            contextWindow: 131072
+            maxTokens: 16384
+            compatibility:
+              supportsDeveloperRole: false
+              supportsReasoningEffort: false
+              supportsStore: false
+              maxTokensField: max_tokens
+          metadataGeneration:
+            disableThinking: true
 authentication:
   configDirectory: "<abs>/projects/ThothII/deploy/psd/auth"
 overrides:

deploy/secrets/README.md

@@ -10,8 +10,9 @@ chmod 600 deploy/secrets/thothii.secrets
 
 The file uses strict `KEY=VALUE` lines (comments and blank lines are allowed). The supported
 installation keys are `THT_MODEL_API_KEY`, `THT_DWH_API_KEY`, `THT_CA`, `THT_SSL_CA`,
-`THT_OIDC_CLIENT_SECRET`, and `THT_AUTHENTIK_API_TOKEN`. Metadata-generation models may reference
-exactly one of `THT_METADATA_API_KEY`, `ANTHROPIC_API_KEY`, `AZURE_API_KEY`, `GEMINI_API_KEY`,
+`THT_OIDC_CLIENT_SECRET`, and `THT_AUTHENTIK_API_TOKEN`. Installation Model Catalog providers may
+reference exactly one of `THT_MODEL_API_KEY`, `THT_METADATA_API_KEY`, `ANTHROPIC_API_KEY`,
+`AZURE_API_KEY`, `GEMINI_API_KEY`,
 `DEEPSEEK_API_KEY`, `OPENAI_API_KEY`, `OPENROUTER_API_KEY`, or `ZAI_API_KEY` through their
 descriptor `apiKeyEnv`. An entry for an explicitly configured endpoint that accepts unauthenticated
 requests may omit `apiKeyEnv`; hosted/default endpoints must always reference a key.
@@ -23,10 +24,10 @@ installation. Other configured values must be non-empty and contain no
 whitespace. Do not put secrets in the root `.env`, installation YAML, workspace YAML, URLs, logs,
 or rendered Compose output.
 
-`THT_MODEL_API_KEY` remains the generic Pi child credential. Metadata generation is a separate
-backend-owned runtime and reads only the key named by its own `metadataGeneration.models[].apiKeyEnv`
-(when present);
-it does not read Pi settings, `PI_AUTH_FILE`, or workspace `llm_policy`.
+Session and metadata-generation runtimes read only the provider key named by
+`modelCatalog.providers.<provider>.authentication.apiKeyEnv`. They share the declaration and
+credential reference, not their execution lifecycle. Pi-owned authentication remains available only
+to session-only built-in providers through `authentication.mode: pi_auth`.
 
 Do not add vector or embedding endpoint credentials to the bundle. Active operator manuals use
 internal Qdrant and Ollama services, so vector/embedding runtime endpoint secrets are not part of
@@ -56,7 +57,7 @@ and only then deleting the old files. The old variables remain a compatibility p
 upgrades, but the documented and tested default is an absolute `THT_SECRETS_FILE` path to the
 protected bundle.
 
-Hosted Pi providers must use a single model key through `THT_MODEL_API_KEY`. Compound providers
+Hosted providers must use one explicitly named catalog key. Compound providers
 (Bedrock, Azure OpenAI Responses, Cloudflare Workers AI/Gateway) fail closed until a
 provider-specific credential adapter is implemented.
 

deploy/secrets/thothii.secrets.example

@@ -2,14 +2,13 @@
 # Values are read as literal strings (no shell expansion or command substitution).
 # Leave unused keys out of the file.
 
-# Hosted model provider (single-key providers only).
-# THT_MODEL_API_KEY=replace-me
-
-# Description Generation only. The selected name must match apiKeyEnv in metadataGeneration.
-# Allowed names: THT_METADATA_API_KEY, ANTHROPIC_API_KEY, AZURE_API_KEY, GEMINI_API_KEY,
+# Hosted catalog provider (single-key providers only). The selected name must match
+# modelCatalog.providers.<provider>.authentication.apiKeyEnv.
+# Allowed names include THT_MODEL_API_KEY, THT_METADATA_API_KEY, ANTHROPIC_API_KEY,
+# AZURE_API_KEY, GEMINI_API_KEY,
 # DEEPSEEK_API_KEY, OPENAI_API_KEY, OPENROUTER_API_KEY, or ZAI_API_KEY.
 # OPENAI_API_KEY=replace-me
-# A model with an explicit unauthenticated endpoint omits apiKeyEnv and needs no bundle entry.
+# A provider with an explicit keyless endpoint uses authentication.mode: none.
 
 # External DWH adapter.
 # THT_DWH_API_KEY=replace-me

deploy/workspaces/example.yaml

@@ -1,8 +1,8 @@
 workspace:
-  schema_version: 3
+  schema_version: 4
   id: example
   name: Example workspace
-  description: Generic example WorkspaceV3 descriptor.
+  description: Generic example WorkspaceV4 descriptor.
   language: en
 
 dwh:
@@ -13,17 +13,6 @@ dwh:
     - postgres_direct
     - rest_api
 
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: example
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-
 evidence:
   source:
     type: filesystem
@@ -35,11 +24,6 @@ evidence:
     max_chunk_chars: 4000
     retain_published_generations: 3
 
-llm_policy:
-  default: zai/glm-5.2
-  allowed:
-    - zai/glm-5.2
-
 diagnostics:
   dwh_rest:
     method: GET

deploy/workspaces/psd.yaml.example

@@ -1,8 +1,8 @@
 workspace:
-  schema_version: 3
+  schema_version: 4
   id: example-workspace
   name: Example Workspace
-  description: Example WorkspaceV3 descriptor.
+  description: Example WorkspaceV4 descriptor.
   language: en
 
 dwh:
@@ -13,17 +13,6 @@ dwh:
     - postgres_direct
     - rest_api
 
-semantic_index:
-  vector_store:
-    engine: qdrant
-    collection: example-workspace
-    dimensions: 1024
-    distance: cosine
-  embedding:
-    provider: ollama_internal
-    model: qwen3-embedding:0.6b
-    dimensions: 1024
-
 evidence:
   source:
     type: filesystem
@@ -35,11 +24,6 @@ evidence:
     max_chunk_chars: 4000
     retain_published_generations: 3
 
-llm_policy:
-  default: zai/glm-5.2
-  allowed:
-    - zai/glm-5.2
-
 diagnostics:
   dwh_rest:
     method: GET

docker-compose.dev.yml

@@ -1,6 +1,5 @@
-# ThothII standalone development/smoke stack.
-# Run with the canonical local env file:
-#   docker compose --env-file deploy/env/local.env -f docker-compose.dev.yml up -d --build
+# ThothII standalone development/smoke base. Model settings are intentionally absent;
+# use `tht start --build`, which adds the generated modelCatalog projection.
 # frontend: http://localhost:8090   backend: http://localhost:8787
 name: thothii-dev
 
@@ -36,8 +35,6 @@ services:
       THT_LLM_URL: ${THT_LLM_URL:-}
       THT_INTERNAL_QDRANT_URL: http://qdrant:6333
       THT_INTERNAL_EMBEDDING_URL: http://embedding:11434
-      THT_INTERNAL_EMBEDDING_MODEL: qwen3-embedding:0.6b
-      THT_INTERNAL_EMBEDDING_DIMENSIONS: "1024"
       MAX_PI_PROCESSES: ${MAX_PI_PROCESSES:-4}
     extra_hosts:
       - "host.docker.internal:host-gateway"
@@ -45,8 +42,6 @@ services:
       - dev-data:/data
       - dev-pi-state:/home/thoth/.pi
       - ${PI_AUTH_FILE:?set PI_AUTH_FILE}:/home/thoth/.pi/agent/auth.json:ro
-      - ./deploy/pi/models.json:/home/thoth/.pi/agent/models.json:ro
-      - ./deploy/pi/settings.json:/home/thoth/.pi/agent/settings.json:ro
       - workspace-registry:/data/workspace-registry
       - workspace-secrets:/data/workspace-secrets
       - ${THT_DEV_EVIDENCE_HOST_PATH:-./evidence}:/data/evidence:ro
@@ -129,7 +124,6 @@ services:
     entrypoint: ["/usr/bin/bash", "/opt/thoth/embedding-model-init.sh"]
     environment:
       OLLAMA_BASE_URL: http://embedding:11434
-      OLLAMA_MODEL: qwen3-embedding:0.6b
       OLLAMA_WAIT_TIMEOUT_SEC: "180"
     volumes:
       - embedding-models:/root/.ollama