What is Codex

Codex is a simple MCP server that provides a Large Language Model (LLM) with tools to access legislative data from the Congress.gov API.

Use cases

Use cases include tracking bill progress, retrieving information on amendments, accessing committee details, and analyzing congressional records.

How to use

To use Codex, clone the repository, set up a virtual environment, install dependencies, and configure it to connect with Claude for Desktop by editing the configuration file with your Congress.gov API key.

Key features

Codex offers over 40 tools categorized into amendments, bills, committees, members, nominations, treaties, congressional records, hearings, and communications, allowing users to retrieve detailed legislative information.

Where to use

Codex can be used in legal research, legislative analysis, and any application requiring access to U.S. legislative data.

Codex

A simple MCP server that provides a LLM with tools for accessing legislative data from the Congress.gov API.

Features

Over 40 tools organized into categories:

• Amendments: List amendments, get details, actions, cosponsors, and text
• Bills: Search and retrieve bill information, actions, amendments, committees, cosponsors, subjects, summaries, and text
• Committees: List committees and get committee details and bills
• Members: Access member information, sponsored and cosponsored legislation
• Nominations: List and get details about presidential nominations
• Treaties: Access treaty information and actions
• Congressional Record: Browse congressional record entries
• Hearings: Search and get details about congressional hearings
• Communications: Access House and Senate communications

Requirements

• Python 3.10+
• uv package manager
• Congress.gov API key (set as CONGRESS_API_KEY environment variable)

Setup

# Clone the repository
git clone https://github.com/mdashley/codex.git
cd codex

# Set up virtual environment
uv venv
source .venv/bin/activate  # On Windows: .venv\Scripts\activate

# Install dependencies
uv sync

Connecting to Claude for Desktop

1. Install Claude for Desktop
2. Configure Claude to use the server by editing ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "codex": {
      "command": "uv",
      "args": [
        "--directory",
        "/ABSOLUTE/PATH/TO/PARENT/FOLDER/codex",
        "run",
        "codex.py"
      ],
      "env": {
        "CONGRESS_API_KEY": "your-api-key-here"
      }
    }
  }
}

3. Restart Claude for Desktop
4. Look for the hammer icon to confirm tools are available

Getting a Congress.gov API Key

To fetch data from the Congress.gov API, you need to request an API key.

Troubleshooting

• Check logs at ~/Library/Logs/Claude/mcp*.log
• Update the uv path in claude_desktop_config.json to be absolute (run which uv to find your uv installation path)

Learn More

• MCP documentation
• Congress.gov API documentation