bvandeusenandClaude Opus 5.5
3984f639e8
Second step of milestone 461. An MCP client (Claude Code, Claude Desktop via mcp-remote, Open WebUI) connects to /mcp with a personal API token. - mcp>=2.2 (SDK v2 MCPServer). Mounted by wrapping app.asgi_app, so /mcp never enters Quart's pipeline; stateless streamable HTTP so a redeploy never strands a client on a session id the new process didn't issue. - Auth: Authorization: Bearer stw_… resolves to a Caller (user + effective role) in a ContextVar; 401 with WWW-Authenticate otherwise. The web pipeline's database gate runs first, so a DB restart answers 503 instead of failing inside a tool. - Registry, default-deny: register_tool(fn, role=, read_only=) is the only door; role and read_only are required. Tools above the caller's role, or from a disabled plugin, are neither listed nor callable. Undeclared arguments are refused (not silently dropped); a tool's ValueError reaches the agent as its reason; a DB failure mid-tool says so. - Plugins contribute tools via an optional register_mcp_tools(register) export, all-or-nothing, replaced on hot-reload. Documented in docs/plugins/writing-a-plugin.md. - First tool: whoami. - Tests drive app.asgi_app directly (Quart's test client never reaches /mcp); the integration test mints a real token against Postgres and runs initialize → tools/list → whoami → revoke → 401. Task #4966 "MCP-2 — /mcp transport". Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>