macOS desktop app unresponsive after 500 errors from server

[Gary-Armstrong]

Description

During a chat session with Opus 4.8, started receiving HTTP 500 errors from the server. Both the macOS desktop app and Claude Code CLI were affected.

• Claude Code CLI: Recovered on its own after the 500 errors.
• macOS desktop app: Became unresponsive and does not respond to any prompts. Force quitting and restarting the app did not resolve the issue — the app remains unresponsive after restart.

Steps to Reproduce

1. Start a chat with Opus 4.8 in the macOS desktop app
2. Server begins returning 500 errors
3. App becomes unresponsive

Expected Behavior

App should recover gracefully after server errors resolve, or at minimum return to a working state after a force quit and restart.

Actual Behavior

App remains unresponsive even after force quit and fresh launch.

Environment

• Platform: macOS
• App: Claude desktop app for macOS
• Model: Opus 4.8

[Gary-Armstrong]

Additional Observations (same reporter)

After the initial report, attempted the following:

1. Created a new chat and sent a simple "test" prompt — no response from the app.
2. Attempted to delete that test chat — it does not disappear from the Recents list.
3. The app simultaneously shows "chat deleted" and "chat not found" for the same delete action.

This suggests the 500 errors left the app in a corrupted state — local cache and server state are out of sync. The simultaneous "deleted"/"not found" messages point to a race condition or stale local state that persists across restarts.

[Gary-Armstrong]

Further Debugging (same reporter)

Cleared ~/Library/Application Support/Claude/ completely while the app was quit, relaunched, and signed in fresh.

• Chats are visible (confirmed server-side state is intact).
• App still does not respond to prompts.
• The reply window redraws (UI updates) but no text appears — suggesting the app receives enough of a response to trigger a UI event, but response content is not arriving.

Clearing local cache did not resolve the issue. Problem appears to be server-side or in the app's network/streaming layer, not local state.

Web app (claude.ai in browser) shows the same project chats and is accessible, but also showed a "Your previous message wasn't sent. You can try again" popup on load — consistent with a stuck in-flight request from the original 500-error incident.

[Gary-Armstrong]

Web App Also Unresponsive (same reporter)

claude.ai in browser also does not respond to prompts. The "Your previous message wasn't sent. You can try again" popup is persistent — clicking retry does not resolve it.

This is reproducible across both the macOS desktop app and the web app, after cache clear and re-authentication. The issue appears to be a stuck server-side session state on this account, not a client-side problem.

[Gary-Armstrong]

Account Fully Blocked (same reporter)

All client-side remediation exhausted. The issue is confirmed server-side, account-level:

• No retry button present on the "Your previous message wasn't sent" popup.
• New chats (not the original project) also unresponsive.
• Fresh sign-in on web: same behavior.
• Incognito window, fresh session: same behavior.

The account cannot send any message on any surface (macOS app, web, incognito). A stuck server-side pending request appears to be blocking all new messages for this account. Needs server-side intervention to clear.

Reporter is contacting support@anthropic.com.