[BUG] GitHub push permission (403) in Claude Code Remote session - read only despite repo being added as source

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?

I’m using a Claude Code Remote/Cowork session with the GitHub repositories Colt-Action/skill-manager and Colt-Action/skill_manager_v2 added as sources.
Claude can read from both repos fine (git ls-remote, git clone, file reads all work), but every git push and every GitHub API write (e.g. via the GitHub MCP tool push_files) fails with:
403 Resource not accessible by integration (via the API) / 403 from the internal git proxy (git push)

I checked:
• GitHub → Settings → Installed GitHub Apps: no app installed
• GitHub → Settings → Authorized OAuth Apps: nothing relevant
• Organization-level installed apps: not applicable, Colt-Action is a personal account, not an org
• claude.ai → Settings → Connectors → GitHub Integration: reconnected (disconnect + reconnect), no change
• claude.ai → Claude Code environment settings (Update cloud environment dialog): no repo-level read/write permission toggle found there

Could you help me find where write access for this session/environment is configured, or confirm whether this is expected behavior and how to enable push access?
Session/environment context: Claude Code Remote (Cowork), repos added via “add_repo”, branch claude/skill-manager-mvp-caom6x.

What Should Happen?

Claude should be able to git push and write to the connected GitHub repository (read access works fine, write access fails with a 403 error - see Error Messages/Logs below).

Error Messages/Logs

1. Start a Claude Code Remote (Cowork) session with a GitHub repo added as a source (read+write expected)
2. Ask Claude to commit and push a change to the repo
3. git push fails with: fatal: unable to access '...': The requested URL returned error: 403
4. GitHub API write calls (e.g. push_files via the GitHub MCP tool) fail with: 403 Resource not accessible by integration
5. Read access works fine (git ls-remote, git clone, file reads all succeed)

Steps to Reproduce

git push:
fatal: unable to access 'http://127.0.0.1:41729/git/<owner>/<repo>/': The requested URL returned error: 403

GitHub API (via MCP push_files):
failed to initialize repository: failed to create initial file: PUT https://api.github.com/repos/<owner>/<repo>/contents/README.md: 403 Resource not accessible by integration []

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Claude Code Remote (Web session)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_