claude-desktop-custom-connectors-require-oauth-dcr-not-bearer

Claude Desktop Custom Connectors implement OAuth 2.0 Dynamic Client Registration (MCP spec 2025-03-26). When a connector endpoint returns 401, Desktop probes /.well-known/oauth-authorization-server, /oauth/authorize, and /oauth/token — if none respond, connection fails entirely. Static Bearer tokens are never forwarded; the connector never reaches /mcp. Only public (no-auth) or OAuth-enabled MCP servers can be Desktop-bridged.