[BUG] Remote Control initialization fails for every new session - registerWorker HTTP 401 (reconnects still work), since mid-May

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Remote Control fails to initialize for every NEW local session, so desktop sessions never appear in the mobile app Code tab. Every session start logs 'Enabling remote control' then 'Failed to toggle remote control: Remote Control initialization failed'. Underlying error: registerWorker: HTTP 401 (SDK) from the sessions API.

Key signal: an existing persisted remote session (created 2026-06-21) reconnects successfully in the same environment (env_01E4R8faUaocbzix6jizn1ik) with a valid user:sessions:claude_code token - but registering a NEW remote worker is always rejected with 401. Reconnect works; create-new fails 100%.

Ruled out: full quit + sign-out/in twice (desktop token refreshed, bridge re-registered environment, old session reconnected fine); brand-new sessions after each refresh still 401 (2026-06-23 08:06:28 and 09:00:23); not a terminal CLI credential issue (desktop SDK uses host auth refresh).

Timeline: first 'Remote Control initialization failed' 2026-05-14; intermittent through May; persistent since ~2026-06-22. Bridge request-ids: req_011CcJy9RKkWRf2i4j11E4Bp, req_011CcKixcHsb5EdD9872osvJ. Support conversation 215474808312935 (7 days, no response). Possibly related: #28758, #60780.

What Should Happen?

A new session should register a remote worker successfully and appear in the Claude mobile app Code tab - as it did before mid-May, and as reconnecting existing sessions still does.

Error Messages/Logs

2026-06-23 08:06:26 [info] Starting local session local_fbb4974e-acb9-4af4-a404-abec5f26619d in C:\Users\noelm\.claude
2026-06-23 08:06:27 [info] Enabling remote control for session local_fbb4974e-acb9-4af4-a404-abec5f26619d
2026-06-23 08:06:28 [error] Failed to toggle remote control for local_fbb4974e-acb9-4af4-a404-abec5f26619d: Remote Control initialization failed
2026-06-23 07:33:00 [info] [sessions-bridge] Transport permanently closed for session cse_01CWgrcD2iDYff5mbvmhzbwL code=401
2026-06-23 07:33:02 [error] [sessions-bridge] Transport reconnect failed for session cse_01CWgrcD2iDYff5mbvmhzbwL: registerWorker: HTTP 401 (SDK) Request failed with status code 401
2026-06-23 07:33:05 [warn] [sessions-bridge] reconnectSession failed during ingress-token refresh for cse_01CWgrcD2iDYff5mbvmhzbwL: ReconnectSession: Failed with status 400: Could not re-queue session. Try again. [request-id: req_011CcKixcHsb5EdD9872osvJ]

Steps to Reproduce

1. Windows desktop app (Claude 1.14271 arm64, bundled Claude Code 2.1.181), signed in with a claude.ai Max account; 'Enable remote control by default' is on.
2. Start any new session (Code tab).
3. Watch %APPDATA%/Claude/logs/main.log: 'Enabling remote control for session ...' is immediately followed by 'Failed to toggle remote control ...: Remote Control initialization failed' (underlying error: registerWorker: HTTP 401 (SDK)).
4. The session never appears in the mobile app Code tab.
5. Contrast: reconnecting an EXISTING persisted remote session in the same environment succeeds - only NEW worker registration fails.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Unknown exact version; failures began 2026-05-14

Claude Code Version

2.1.181 (Claude Code) - bundled in Windows desktop app Claude 1.14271.0.0 arm64

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

Account: claude.ai Max subscription (OAuth first-party), single-user org, user is org admin. Remote control was previously working on this machine (hasUsedRemoteControl=true); existing session cse_01CWgrcD2iDYff5mbvmhzbwL still reconnects and is steerable, only NEW registrations 401. Environment: env_01E4R8faUaocbzix6jizn1ik. Anthropic support conversation: 215474808312935 (filed 2026-06-23, no human response as of 2026-07-01). Full main.log available on request.