LegiScan MCP Server

A Model Context Protocol (MCP) server that provides access to the LegiScan API for legislative data from all 50 US states and Congress.

Features

• 10 Streamlined MCP Tools optimized for legislative research workflows
• Composite tools that batch multiple API calls (90%+ reduction in API usage)
• Full TypeScript type definitions for all API responses
• Bill number normalization (handles AB 858, AB858, AB-858 formats)

Installation

From npm (Recommended)

npm install -g legiscan-mcp-server

From Source

git clone https://github.com/sh-patterson/legiscan-mcp.git
cd legiscan-mcp
npm install
npm run build

Setup

1. Get a LegiScan API Key

1. Create a free account at LegiScan
2. Register for API access at https://legiscan.com/legiscan
3. Copy your API key

2. Add to Claude Desktop

Add to your Claude Desktop configuration:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%\Claude\claude_desktop_config.json

Using npx (Recommended)

{
  "mcpServers": {
    "legiscan": {
      "command": "npx",
      "args": ["-y", "legiscan-mcp-server"],
      "env": {
        "LEGISCAN_API_KEY": "your_api_key_here"
      }
    }
  }
}

Using local installation

{
  "mcpServers": {
    "legiscan": {
      "command": "node",
      "args": ["/path/to/legiscan-mcp-server/dist/index.js"],
      "env": {
        "LEGISCAN_API_KEY": "your_api_key_here"
      }
    }
  }
}

Available Tools

Composite Tools (High-Level Research)

Tool	Description
legiscan_find_legislator	Find a legislator's people_id by name. Supports partial matching.
legiscan_get_legislator_votes	Get how a legislator voted on multiple bills in one call.
legiscan_get_primary_authored	Get only bills where legislator is primary author (not co-sponsor).

Bills

Tool	Description
legiscan_get_bill	Get detailed bill info (sponsors, history, votes, texts)
legiscan_find_bill_by_number	Find bill by number (handles AB 858, AB858, AB-858)
legiscan_get_roll_call	Get vote details with individual legislator votes

People

Tool	Description
legiscan_get_person	Get legislator info with third-party IDs (VoteSmart, OpenSecrets, etc.)
legiscan_get_session_people	Get all legislators active in a session

Search

Tool	Description
legiscan_search	Full-text search across legislation

Sessions

Tool	Description
legiscan_get_session_list	List available legislative sessions by state

Usage Examples

Find a legislator and get their voting record

1. Use legiscan_find_legislator with name="Smith" state="TX"
2. Use legiscan_get_legislator_votes with people_id and bill_ids

Get all primary authored bills for a legislator

Use legiscan_get_primary_authored with people_id=12345 state="TX"

Find a specific bill by number

Use legiscan_find_bill_by_number with state="CA" bill_number="AB 858"

Search for bills about a topic

Use legiscan_search with query="climate change" state="CA"

Get detailed information about a specific bill

Use legiscan_get_bill with bill_id=1234567

API Call Reduction

The composite tools dramatically reduce API calls for common workflows:

Workflow	Without Composites	With Composites
Get votes for 1 legislator on 10 bills	~80 calls	1 call
Filter primary authored from 150 sponsored	~150 calls	1 call
Find legislator by name	2 calls	1 call

Development

npm run build        # Compile TypeScript
npm test             # Run unit tests
npm run test:e2e     # Run E2E tests (requires API key)
npm run lint         # Check for lint errors
npm run format       # Format code with Prettier

API Limits

• Free public API keys have a 30,000 queries per month limit
• Composite tools batch requests (10 concurrent max) to avoid rate limits
• The composite tools help you stay within limits by reducing total API calls

License

MIT - see LICENSE for details.