cdgmcp

A Model Context Protocol (MCP) server that exposes a Congress.gov-style legislative GraphQL API to MCP clients (such as VS Code, Claude Desktop, or other agents). It provides high-level tools for querying bills, actions, committee activities and cosponsors, plus a raw GraphQL escape hatch for advanced queries.

Features

Tools

Tool	Description
search_bills	Search/list bills with filters (congress, chamber, type, title, latest action, dates, sponsor).
get_bill	Fetch a single bill's full details, with optional actions, cosponsors, committee activities, titles and text versions.
search_committee_activities	Find committee referrals/activities and their related bills.
search_actions	Search the legislative action history (e.g. "Passed House", "Became Public Law").
search_cosponsors	Search cosponsorship records across bills.
get_node	Fetch any object directly by its Relay global id.
graphql_query	Run an arbitrary read-only GraphQL query (mutations rejected).

The API is built with Hot Chocolate 16.2.0 and follows Relay conventions. The search tools are connection-based: each returns pageInfo.endCursor, which you can pass back as the after argument to fetch the next page.

Resources

URI	Description
cdg://schema	The live GraphQL schema (SDL).
cdg://guide	Data model and usage guide.
cdg://endpoint	The configured GraphQL endpoint.

Example questions it can answer

• What bills have been recently introduced in the House or Senate?
• What bills have passed the House or Senate and became law recently?
• What bills have been referred to the Commerce Committee recently?
• Of the bills referred to the Agriculture Committee, which cosponsors recur across them?

Configuration

The GraphQL endpoint defaults to http://dotnet10-dev:5208/graphql/. Override it with the CDG_GRAPHQL_ENDPOINT environment variable.

Build & run

npm install
npm run build
npm start          # or: node dist/index.js

For development (no build step) use:

npm run dev        # runs src/index.ts via tsx

Use with VS Code

Add to your .vscode/mcp.json (or user mcp.json):

{
  "servers": {
    "cdgmcp": {
      "command": "node",
      "args": ["${workspaceFolder}/cdgmcp/dist/index.js"],
      "env": {
        "CDG_GRAPHQL_ENDPOINT": "http://dotnet10-dev:5208/graphql/"
      }
    }
  }
}

The server communicates over stdio.

This is supposed to be a standalone testing something, but I haven't seen it work.

HOST=0.0.0.0 npx @modelcontextprotocol/inspector node dist/index.js