Remote Control: remoteControlAtStartup never connects in VS Code/Cursor extension sessions (manual /rc works)

Summary

With remoteControlAtStartup: true in ~/.claude/settings.json, sessions started from the VS Code/Cursor extension never register a Remote Control bridge, so they never appear at claude.ai/code or in the Claude mobile app. Running /rc manually in the same environment works and the session shows up immediately, so this is specific to the auto-start path.

The extension itself advertises this capability: its settings schema describes remoteControlAtStartup as "Start Remote Control bridge automatically each session", and the command menu exposes a toggle (remote-control-at-startup).

Environment

• Claude Code: 2.1.220 (extension build anthropic.claude-code-2.1.220-darwin-arm64)
• Cursor: 3.13.25
• macOS 26.5.2, arm64
• Auth: claude.ai OAuth (Max), no ANTHROPIC_API_KEY, no ANTHROPIC_BASE_URL
• No DISABLE_TELEMETRY / DO_NOT_TRACK / CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC / DISABLE_GROWTHBOOK
• No disableRemoteControl in user, project, or managed settings
• claude remote-control --help prints the flag list (i.e. the eligibility check passes)
• Workspace trust accepted for the project directory

Settings

~/.claude/settings.json (user scope):

{
  "remoteControlAtStartup": true,
  "agentPushNotifEnabled": true,
  "inputNeededNotifEnabled": true
}

The command-menu toggle was also flipped off and back on to force a write. The extension log confirms both writes went through:

Received message from webview: {"type":"request","request":{"type":"apply_settings","settings":{"remoteControlAtStartup":false}}}
Received message from webview: {"type":"request","request":{"type":"log_event","eventName":"remote_control_at_startup_setting_changed","eventData":{"enabled":false}}}
Received message from webview: {"type":"request","request":{"type":"apply_settings","settings":{"remoteControlAtStartup":true}}}
Received message from webview: {"type":"request","request":{"type":"log_event","eventName":"remote_control_at_startup_setting_changed","eventData":{"enabled":true}}}

Steps to reproduce

1. Set remoteControlAtStartup: true in ~/.claude/settings.json (or enable "Enable Remote Control for all sessions" from the extension command menu).
2. Fully quit and reopen Cursor (not just Developer: Reload Window).
3. Open a new Claude conversation in the extension in a trusted project directory.
4. Open claude.ai/code or the Claude mobile app (Code tab).

Expected

The new session appears in the session list with a computer icon and green status dot, without any manual command.

Actual

The session never appears. No connection banner appears above the prompt box either. Running /rc in that same session does work: the session then appears in the mobile app immediately.

Session state files show these sessions are registered as interactive:

{"pid":23626,"version":"2.1.220","kind":"interactive","entrypoint":"claude-vscode","name":"exosign-50"}

Additional observations

• The extension log (Anthropic.claude-code/Claude VSCode.log) contains no Remote Control lines at all, in either the auto-start case or after a successful manual /rc. That makes this hard to diagnose from the client side. Some bridge lifecycle logging would help.
• Unverified, but possibly related: launching the CLI the way the extension does (claude --output-format stream-json --input-format stream-json ...) with --remote-control "NAME" is accepted without error, yet produces no additional established connections compared to an identical run without the flag, and no remote-control lines under --debug --debug-to-stderr. If the auto-start path goes through the same code as that flag in non-TUI mode, that may be where it is being skipped.