mcp-docs-server

A single FastMCP 3.1.x server that fronts multiple documentation MCP servers (FastMCP, Google Developer, Cloudflare, AWS Knowledge, Microsoft Learn) and exposes them to LLMs through Code Mode — so the client only sees three discovery tools (search, get_schema, execute) regardless of how many doc tools the backends expose.

Auth is Okta OIDC via MultiAuth (interactive OAuth + bearer introspection), inlined from the mcp-deploy-utils pattern so there is no external package dependency at deploy time.

Why

Documentation lookups are usually multi-step: resolve a library / service, fetch a page, maybe chase a cross-reference. Code Mode lets the LLM write a short Python block that does all of that inside a sandbox and returns only the answer — keeping both the tool catalog and the intermediate results out of the LLM's context window.

Architecture

┌─────────────────────────────────────────────────────────────┐
│  mcp-docs-server  (FastMCP 3.1.x on fastmcp.cloud)          │
│                                                             │
│    MultiAuth (Okta OIDCProxy + Introspection, optional)     │
│        │                                                    │
│        ▼                                                    │
│    CodeMode transform                                       │
│      exposes: search / get_schema / execute                 │
│        │                                                    │
│        ▼                                                    │
│    ProxyProvider (from backends.yaml)                       │
│      prefixes: fastmcp_*, google_*, cloudflare_*, aws_*,    │
│                mslearn_*                                    │
└────────────┬──────────────┬──────────────┬──────────────────┘
             ▼              ▼              ▼
      FastMCP Docs    Cloudflare Docs  AWS Knowledge   …

The SkillProvider also exposes skill://docs-router/SKILL.md as an MCP resource so any client — Claude Code, Claude Desktop, Claude Web, Copilot, VSCode extensions, Codex — can read the usage guide directly.

Development

uv sync
uv run pytest
uv run python server.py   # runs on http://127.0.0.1:8000/mcp

Auth is opt-in: without OKTA_CLIENT_SECRET the server runs unauthenticated, which is convenient for local development.

Deployment (fastmcp.cloud)

1. Push this repo to GitHub.
2. Connect it to fastmcp.cloud. The fastmcp.json manifest tells fastmcp.cloud which env vars to expose.
3. Set Okta env vars in the fastmcp.cloud dashboard (same tenant as moon-d1-mcp): OKTA_CLIENT_ID, OKTA_CLIENT_SECRET, OKTA_DOMAIN, OKTA_ISSUER, MCP_BASE_URL, JWT_SIGNING_KEY.
4. Optional per-backend credentials (only if a backend requires bearer auth): AWS_KNOWLEDGE_BEARER_TOKEN, GITHUB_DOCS_BEARER_TOKEN, …

Backend credentials resolve lazily. A missing env var skips that backend and logs a warning — the server still starts with whatever backends are configured.

Adding a backend

Edit backends.yaml:

- id: mybackend
  name: My Docs
  url: https://example.com/mcp
  transport: http
  auth: { type: bearer, token_env: MYBACKEND_BEARER_TOKEN }
  tags: [custom]
  enabled: true

Add MYBACKEND_BEARER_TOKEN to fastmcp.json and to the fastmcp.cloud dashboard. Tools from the backend automatically appear prefixed as mybackend_*.

v2 ideas (not implemented)

• In-process result cache for repeated doc queries (guarded by an env flag).
• Per-backend health dashboard.