Cowork composer locks when /model_configs/claude-opus-4-7[1m] returns 404

Summary

In the Cowork view of the desktop app, the entire composer (text input, model dropdown, send button, sidebar items) becomes unresponsive after the renderer fails to fetch the model config for the 1M-context Opus 4.7 variant. The conversation is still streaming text into the message pane, but no UI controls accept clicks or keystrokes until Cmd+R forces a renderer reload.

Root cause (from logs)

The renderer issues GET /api/organizations/{org}/model_configs/claude-opus-4-7[1m] and the API responds 404 Not Found. With no model config loaded, the composer never re-enables.

2026-05-14 09:02:51 [error] [REACT_QUERY_CLIENT] QueryClient error:
  {"type":"not_found_error","statusCode":404,
   "endpoint":"/api/organizations/{org}/model_configs/claude-opus-4-7[1m]",
   "method":"GET","message":"Not found"}

The same 404 fires repeatedly across sessions (first hit on 2026-05-13, multiple times on 2026-05-14). Org UUID redacted.

Prior occurrence

The identical pattern occurred on 2026-04-08 with the previous-gen model — claude-opus-4-6[1m] — same endpoint shape, same [REACT_QUERY_CLIENT] 404, same lock-up symptom. Suggests this is a recurring regression each time a new Opus version ships without its [1m] variant being registered on the org/model-config service.

2026-04-08 12:14:06 [error] [REACT_QUERY_CLIENT] QueryClient error:
  endpoint: /api/organizations/{org}/model_configs/claude-opus-4-6[1m]
  statusCode: 404

Workaround

Cmd+R reloads the renderer; the retry sometimes succeeds and the composer becomes interactive again. Conversation state is preserved (server-side).

Two bugs, really

1. Backend: the [1m] variant of newly-released Opus models isn't being provisioned in model_configs for at least some orgs.
2. Frontend: a 404 on model_configs/... should degrade gracefully (fall back to base model, surface a banner) instead of locking the entire Cowork UI silently.

Environment

• App: Claude 1.7196.0 (Electron 41.5.0, Chrome 146.0.7680.216)
• OS: macOS Darwin 25.3.0 (arm64, M4 Max)
• Selected model in dropdown: "Opus 4.7" (the 1M variant)
• Mode: Cowork