Public APIs MCP

Catalog of free public APIs with semantic search.

The catalog includes an extensive list of APIs from the public-apis GitHub
repo.
Thank you to all the maintainers, contributors and API creators! 💯

🎯 Features

search_public_apis: embedding-based search over API names and descriptions
get_public_api_details: retrieve full details by id
Resources: public-apis://apis, public-apis://api/{id}

🔧 Setup (uv)

Add to MCP clients (e.g., Claude Desktop) using uv.

Claude Desktop

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "public-apis": {
      "command": "uvx",
      "args": ["public-apis-mcp"]
    }
  }
}

🚀 Usage

Build embeddings index (optional; auto-build on first search):

uvx public-apis-mcp build-index

Run the MCP server over STDIO:

uvx public-apis-mcp run

📋 Tool Reference

`search_public_apis`

Purpose: Semantic search over the catalog
Parameters: query (str), limit (int, default 5)
Returns: list of { id, name, score, snippet }

Example call payload:

{ "name": "search_public_apis", "arguments": { "query": "weather", "limit": 5 } }

`get_public_api_details`

Purpose: Fetch full details by id
Parameters: id (str)
Returns: ApiItem

Example call payload:

{ "name": "get_public_api_details", "arguments": { "id": "a6b3a6b3-a6b3-a6b3-a6b3-a6b3a6b3a6b3" } }

🛠️ Development

Prerequisites:

Python 3.10+
uv (https://docs.astral.sh/uv/)

Setup:

uv sync --dev

Run tests:

FREE_APIS_MCP_TEST_MODE=1 uv run pytest -q

Lint and format:

uv run ruff check --fix
uv run ruff format

Type checking:

uv run mypy src/

MCP Client Dev Config

{
  "mcpServers": {
    "public-apis-dev": {
      "command": "uv",
      "args": [
        "--directory",
        "<abs_path>/public-apis-mcp",
        "run",
        "public-apis-mcp"
      ]
    }
  }
}

Build and Try

uv build
uv run --with dist/*.whl public-apis-mcp --help

📦 Data & Index

Data: src/public_apis_mcp/datastore/free_apis.json
Embedding index: src/public_apis_mcp/datastore/index.npz (auto-built)

Testing with MCP Inspector

For exploring and/or developing this server, use the MCP Inspector npm utility:

# Install MCP Inspector
npm install -g @modelcontextprotocol/inspector

# Run local development server with the inspector
npx @modelcontextprotocol/inspector uv run public-apis-mcp

# Run PyPI production server with the inspector
npx @modelcontextprotocol/inspector uvx public-apis-mcp

📝 License

MIT License - see LICENSE file for details.

🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.