mcp-oidc-proxy

Local prototype for exercising FastMCP OIDCProxy against a demo OIDC provider.

The repository packages two cooperating apps:

• Auth server — a NanoIDP demo OIDC provider on http://127.0.0.1:9000

• MCP server — a FastMCP HTTP server on http://127.0.0.1:8000 with a single protected hello_world tool

Together they prove that an MCP client can authenticate through OIDCProxy, call a protected tool, and be rejected when unauthenticated.

Prerequisites

• uv

• Python 3.14+

Related MCP server: Auth0 OIDC MCP Server

Setup

uv sync
cp .env.example .env

Demo client credentials are committed in config/ with defaults matching .env.example. Both servers read the same environment variable names so credentials stay aligned.

Running locally

Run each server in its own terminal from the repository root:

uv run python -m nanoidp

uv run launch-mcp

The auth server listens on http://127.0.0.1:9000 and exposes standard OIDC discovery, JWKS, authorize, and token endpoints. NanoIDP reads committed configuration from ./config.

Demo-only warning: the auth server exists solely to validate the OIDC proxy flow during local development and testing. It is not a production identity provider.

Demo credentials:

• User: admin / admin

• OAuth client: values from .env.example (mcp-proxy-client / dev-secret)

Tests

uv run pytest          # unit/integration tests (smoke excluded)
uv run pytest -m smoke # end-to-end smoke tests (spawns both servers)

Smoke tests launch real subprocesses for NanoIDP and the MCP server, complete the OAuth flow with FastMCP HeadlessOAuth, and verify both authenticated and unauthenticated tool calls.