Machine Library MCP server

Machine Library MCP Server

Machine Library is the search and AI product by Space Frontiers Company. Existing accounts, API keys, and spacefrontiers_* tool names remain compatible. The original https://mcp.spacefrontiers.org endpoint is still supported.

A retrieval layer for AI agents over peer-reviewed papers, books, patents, standards, Wikipedia, Reddit, Telegram, Discord, and YouTube. Returns bounded full text and canonical source URIs for citation.

Hosted at https://mcp.machinelibrary.ai/ (Streamable HTTP transport, OAuth 2.1 with PKCE or Bearer API key).

Try a worked example: Find research, inspect supporting passages, and retain citations. Includes exact tool calls and observations from a live run, plus a small evaluation checklist for research teams.

Tools

The four core retrieval tools below are read-only, idempotent, and prefixed spacefrontiers to avoid collisions in multi-server agent setups. The hosted service may expose additional tools; inspect its current tools/list. In particular, the optional spacefrontierstopupbalance capability purchases prepaid credits and is not a read-only retrieval tool.

Search defaults to 10 compact, hybrid-ranked results and is capped at 30. Every hit includes a canonical sourceuri, one snippet (up to 900 characters), an abstract preview (up to 800 characters), score, authors, date, type, and estimated full-text size. Citation backlinks are opt-in on spacefrontiersfetch_document because they add another billed search.

Install

The hosted server has its own /mcp install page with one-click links for Cursor, VS Code, and Smithery.

Claude Code (recommended)

claude mcp add --transport http --scope user spacefrontiers https://mcp.machinelibrary.ai

On first use a browser opens for OAuth login — no API key paste required.

Cursor / VS Code / Cline / Windsurf (HTTP)

{
  "mcpServers": {
    "spacefrontiers": {
      "type": "http",
      "url": "https://mcp.machinelibrary.ai",
      "headers": { "Authorization": "Bearer YOUR_API_KEY" }
    }
  }
}

Get an API key at https://machinelibrary.ai/keys.

Self-hosted (stdio)

git clone https://github.com/SpaceFrontiers/mcp.git
cd mcp
uv sync
SEARCH_API_ENDPOINT=https://api.machinelibrary.ai \
SPACE_FRONTIERS_API_KEY=sf_live_xxx uv run fastmcp run mcp_server.py

The environment variable is used as the upstream API credential in stdio mode. The command selects the public Machine Library API with SEARCHAPIENDPOINT. The internal default remains http://search-api for existing deployments. For HTTP deployments, set SEARCHAPIENDPOINT to your trusted internal search API and USERSAPIENDPOINT to your internal users API; the auth middleware forwards verified identity headers to that internal service. OAuth retains the compatible authorization-server issuer at https://api.spacefrontiers.org; browser sign-in for the new product uses https://machinelibrary.ai with the same accounts.

Pricing

Shortened. The full README is on GitHub.