fix: fail safe on missing workspace revisions

frontend/src/shell/SteerInput.test.tsx

@@ -389,6 +389,35 @@ test("initial submit rejects a migration-required workspace after summaries load
   expect(body).toBeUndefined();
 });
 
+test("initial submit rejects a workspace summary that omits the canonical revision", async () => {
+  let body: unknown;
+  let failure: string | undefined;
+  localStorage.setItem("thothii.workspace-registry.v1.preferences", JSON.stringify({
+    workspaceId: "broken-workspace", provider: "zai", model: "glm-5.2", thinking: "medium",
+  }));
+  server.use(
+    http.get("/api/settings", () => HttpResponse.json({ workspace: "broken-workspace" })),
+    http.get("/api/workspaces", () => HttpResponse.json([{
+      id: "broken-workspace", name: "broken-workspace", file: "broken-workspace.yaml", displayName: "Broken workspace",
+    }])),
+    http.get("/api/models", () => HttpResponse.json({ models: [
+      { provider: "zai", id: "glm-5.2", name: "GLM-5.2", reasoning: true },
+    ] })),
+    http.post("/api/sessions", async ({ request }) => {
+      body = await request.json();
+      return HttpResponse.json({ id: "s1" });
+    }),
+  );
+  const client = new QueryClient({ defaultOptions: { queries: { retry: false } } });
+  render(<QueryClientProvider client={client}><ComposerFooter /><SteerInput sessionId={null} onSessionCreateFailed={(message) => { failure = message; }} /></QueryClientProvider>);
+
+  await userEvent.type(screen.getByRole("textbox", { name: /new question/i }), "q");
+  await userEvent.click(screen.getByRole("button", { name: /send/i }));
+
+  await waitFor(() => expect(failure).toBe("Could not load selected workspace policy. Please retry."));
+  expect(body).toBeUndefined();
+});
+
 test("failed workspace summaries block creation and report a safe error", async () => {
   let body: unknown;
   let failure: string | undefined;

frontend/src/shell/SteerInput.tsx

@@ -180,12 +180,11 @@ export function ComposerFooter() {
 
   const workspace = preferences.workspaceId ?? settings?.workspace ?? "";
   const selectedWorkspace = workspaces.find((candidate) => candidate.id === workspace);
+  const selectedWorkspaceHasRevision = Boolean(selectedWorkspace?.revision);
   const { data: workspaceRecord, isError: workspacePolicyError } = useQuery({
     queryKey: ["workspace", workspace],
     queryFn: () => getWorkspace(workspace),
-    // Legacy metadata responses do not carry a registry revision, so retain the
-    // existing selector behavior without issuing an incompatible detail request.
-    enabled: Boolean(selectedWorkspace?.revision),
+    enabled: selectedWorkspaceHasRevision,
   });
   const model = preferences.model ?? settings?.model ?? "";
   const thinking = preferences.thinking ?? settings?.thinking ?? "medium";
@@ -202,6 +201,8 @@ export function ComposerFooter() {
       workspacePolicyGate.beginSummary(workspace);
     } else if (workspaceSummariesError) {
       workspacePolicyGate.rejectSummary(workspace);
+    } else if (selectedWorkspace && !selectedWorkspaceHasRevision) {
+      workspacePolicyGate.rejectSummary(workspace);
     } else if (selectedWorkspace?.revision?.state === "migration_required") {
       workspacePolicyGate.rejectSummary(workspace);
     } else if (selectedWorkspace?.revision) {
@@ -241,7 +242,8 @@ export function ComposerFooter() {
   function update(patch: WorkspacePreference) {
     if (patch.workspaceId && patch.workspaceId !== workspace) {
       const selected = workspaces.find((candidate) => candidate.id === patch.workspaceId);
-      if (selected?.revision?.state === "migration_required") workspacePolicyGate.rejectSummary(patch.workspaceId);
+      if (selected && !selected.revision) workspacePolicyGate.rejectSummary(patch.workspaceId);
+      else if (selected?.revision?.state === "migration_required") workspacePolicyGate.rejectSummary(patch.workspaceId);
       else if (selected?.revision) workspacePolicyGate.select(patch.workspaceId);
       else workspacePolicyGate.allowLegacy(patch.workspaceId);
     }
@@ -267,7 +269,7 @@ export function ComposerFooter() {
           {workspaces.length === 0 ? (
             <option value="">— workspace —</option>
           ) : (
-            workspaces.filter((w) => w.revision?.state !== "migration_required").map((w) => (
+            workspaces.filter((w) => w.revision && w.revision.state !== "migration_required").map((w) => (
               <option key={w.name} value={w.name}>
                 {w.name}
               </option>

frontend/src/shell/WorkspaceManager.test.tsx

@@ -232,6 +232,24 @@ test("shows a migration banner for legacy descriptors and does not load editor d
   expect(screen.queryByLabelText("Vector collection")).not.toBeInTheDocument();
 });
 
+test("shows an actionable unavailable message when a workspace summary omits its canonical revision", async () => {
+  const user = userEvent.setup();
+  server.use(
+    http.get("/api/workspaces", () => HttpResponse.json([
+      {
+        id: "broken-workspace", name: "Broken workspace", displayName: "Broken workspace", description: "Broken data",
+        language: "en", file: "workspaces/broken-workspace.yaml",
+      },
+    ])),
+  );
+  renderManager();
+
+  await user.click(await screen.findByRole("button", { name: "Broken workspace" }));
+
+  expect(await screen.findByText("This workspace summary is incomplete. Refresh the registry or choose another workspace before creating sessions or editing drafts.")).toBeVisible();
+  expect(screen.queryByLabelText("Vector collection")).not.toBeInTheDocument();
+});
+
 test("shows an accessible retry instead of a loading status when the registry status query fails", async () => {
   const user = userEvent.setup();
   let calls = 0;

frontend/src/shell/WorkspaceManager.tsx

@@ -63,11 +63,12 @@ export function WorkspaceManager({ open, onClose }: { open: boolean; onClose: ()
   const workspacesQuery = useQuery({ queryKey: ["workspaces"], queryFn: listWorkspaces, enabled: open });
   const workspaces = workspacesQuery.data ?? [];
   const selectedSummary = useMemo(() => workspaces.find((workspace) => workspace.id === selectedId), [selectedId, workspaces]);
-  const selectedIsLegacy = selectedSummary?.revision.state === "migration_required";
+  const selectedSummaryIncomplete = Boolean(selectedSummary && !selectedSummary.revision);
+  const selectedIsLegacy = selectedSummary?.revision?.state === "migration_required";
   const detailQuery = useQuery({
     queryKey: ["workspace", selectedId],
     queryFn: () => getWorkspace(selectedId!),
-    enabled: Boolean(open && selectedId && !localDraft && !selectedIsLegacy),
+    enabled: Boolean(open && selectedId && !localDraft && !selectedSummaryIncomplete && !selectedIsLegacy),
   });
   const status = statusQuery.data;
   const record = detailQuery.data;
@@ -311,13 +312,18 @@ export function WorkspaceManager({ open, onClose }: { open: boolean; onClose: ()
           </nav>
 
           <div className="min-w-0 overflow-y-auto px-5 py-5">
-            {selectedIsLegacy ? (
+            {selectedSummaryIncomplete ? (
+              <div className="rounded-md border border-amber-500/30 bg-amber-500/10 px-4 py-3 text-sm">
+                <p className="font-semibold">Workspace summary unavailable</p>
+                <p className="mt-1">This workspace summary is incomplete. Refresh the registry or choose another workspace before creating sessions or editing drafts.</p>
+              </div>
+            ) : selectedIsLegacy ? (
               <div className="rounded-md border border-amber-500/30 bg-amber-500/10 px-4 py-3 text-sm">
                 <p className="font-semibold">Migration required</p>
                 <p className="mt-1">This workspace uses a legacy descriptor and must be migrated to schema v3 before new sessions or publication.</p>
               </div>
             ) : detailQuery.isError && selectedId && !localDraft ? <QueryError name="Workspace details failed" message="Could not load workspace details." retryLabel="Retry workspace details" onRetry={() => { void detailQuery.refetch(); }} /> : !currentDraft && !detailQuery.isLoading && <div className="grid min-h-64 place-items-center text-center"><div><h3 className="font-heading font-semibold">Select a workspace</h3><p className="mt-1 text-sm text-muted-foreground">Review an existing definition or start a browser-only draft.</p></div></div>}
-            {!selectedIsLegacy && !detailQuery.isError && (currentDraft || detailQuery.isLoading) && (
+            {!selectedSummaryIncomplete && !selectedIsLegacy && !detailQuery.isError && (currentDraft || detailQuery.isLoading) && (
               <>
                 {detailQuery.isLoading && !currentDraft ? <p className="text-sm text-muted-foreground">Loading workspace definition…</p> : currentDraft && <>
                   <div className="mb-5 flex flex-wrap items-start justify-between gap-3 border-b border-border/70 pb-4">