[BUG] Remote-Control does not work on iPhone 17Pro within Claude App / Code

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?

Bug Description
Remote Control works correctly in the browser (both on desktop and mobile Safari), but fails in the Claude iOS app with the error: "Message could not be sent. An unknown network error occurred. Please try again."

Actual Behavior
The iOS app connects and displays the session, but every message attempt fails with: "Message could not be sent. An unknown network error occurred. Please try again."

Environment

• OS: macOS (Mac Mini M4)
• Claude Code version: 2.1.87
• Login method: Claude Pro Account
• Device: iPhone 17 Pro
• Claude iOS app: latest version
• Network: standard home network, no VPN or proxy on the Mac
• curl -I https://api.anthropic.com returns HTTP/2 404 (expected)

What Should Happen?

Messages sent from the Claude iOS app should be relayed to the local Claude Code session, the same way the browser interface works.

Error Messages/Logs

Steps to Reproduce

1. Start a Remote Control session in the terminal: claude remote-control
2. Terminal shows: Connected · [session name] · Capacity: 1/32 · Attached
3. A bridge URL is displayed (https://claude.ai/code?bridge=...)
4. Opening the bridge URL in Safari (desktop or mobile) works correctly — messages can be sent and received
5. Opening the same URL in the Claude iOS app (or scanning the QR code) shows the session, allows selecting the computer, but fails when sending any message

Claude Model

Sonnet (default)

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.1.87

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

• Re-login via /login does not fix the issue
• QR code scanning opens the app and shows the session, but the same send error occurs
• Browser workaround (Safari on iPhone) works fine as a temporary fix
• Similar to #29698 but specifically about the iOS app failing while the browser succeeds