[BUG] API Error 400: tool_use.caller extra input when transferring to remote session

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?

When attempting to transfer a local session to remote using &, the loading spinner continues indefinitely and eventually fails with:

API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.1.content.2.tool_use.caller: Extra inputs are not permitted"}}

What Should Happen?

The session should successfully transfer to Claude Code for Web (remote) and continue the conversation there.

Error Messages/Logs

API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.1.content.2.tool_use.caller: Extra inputs are not permitted"},"request_id":"req_011CWuD6NtWTscNB8wvSCrj3"}

Steps to Reproduce

1. Start a local Claude Code session
2. Use & to transfer session to remote (Claude Code for Web)
3. Loading spinner continues indefinitely
4. Eventually fails with API Error 400

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.1

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

• Claude Code version: 2.1.1
• OS: macOS (Darwin 25.0.0)
• /teleport command is not visible in /help despite being listed in CHANGELOG for v2.1.0
• /remote-env also not visible

Tested on both iTerm2 and Ghostty with same result.