[GitHub integration] Chat says "no GitHub connector available" even though account is connected and Claude GitHub App is installed

Screenshot

No screenshot attached. Customize > Connectors > GitHub Integration shows all green: "GitHub account connected" and "Claude GitHub App: DataDoesYou - Installed (Personal)". In the same account, a claude.ai chat still reports that no GitHub connector is available.

What were you trying to do?

Use the GitHub integration from Claude: in a claude.ai chat (Opus 5.5) I asked Claude to use GitHub to tell me about a project in a GitHub org I belong to, expecting it to read the org's private repos through my connected GitHub account.

What happened instead?

• claude.ai chat: Claude replied "There isn't a GitHub connector available here" and fell back to web search of public GitHub pages, so it could not see anything private.
• Claude Code desktop app: the GitHub plugin MCP server (plugin:github:github) fails to connect with: 400 "Error POSTing to endpoint: bad request: Authorization header is badly formatted".

Meanwhile the connector settings page shows the GitHub account connected and the Claude GitHub App installed on my personal account, so the integration looks healthy in settings but isn't usable in either chat or Claude Code.

Diagnostics

Filed from: GitHub settings for Claude Code on claude.ai
Report code: GH-FXXMMA
Page: claude.ai/customize/connectors/integration-github
Client: web