Katzilla

300+ free public & government data sources behind one API key — the data API for AI agents.

Katzilla aggregates primary-source public data — US federal, case law, health, hazards, economics, 17+ international open-data portals, Eurostat, ECB, WHO, OECD, IMF, World Bank, and more — behind a single REST API and MCP server. Every response ships with structured citation metadata (source, license, URL, update frequency) and quality scoring (freshness, uptime, completeness, confidence).

Get a free API key at https://katzilla.dev/dashboard.

MCP Server

The fastest way to use Katzilla is as an MCP server in Claude Desktop, Cursor, Windsurf, Continue, or any stdio MCP client.

Claude Desktop

Edit claude_desktop_config.json:

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

{
  "mcpServers": {
    "katzilla": {
      "command": "npx",
      "args": ["-y", "@katzilla/mcp"],
      "env": {
        "KATZILLA_API_KEY": "kz_your_key_here"
      }
    }
  }
}

Cursor

Add to ~/.cursor/mcp.json (or project-local .cursor/mcp.json):

{
  "mcpServers": {
    "katzilla": {
      "command": "npx",
      "args": ["-y", "@katzilla/mcp"],
      "env": {
        "KATZILLA_API_KEY": "kz_your_key_here"
      }
    }
  }
}

Restart the client — Katzilla's tools show up in the MCP menu. Full MCP package docs: packages/mcp/README.md.

TypeScript SDK

npm install @katzilla/sdk

import { Katzilla } from "@katzilla/sdk";

const kz = new Katzilla({ apiKey: process.env.KATZILLA_API_KEY! });

const quakes = await kz.agent("hazards").action("usgs-earthquakes", {
  minMagnitude: 5,
});
console.log(quakes.data, quakes.citation);

REST API

curl -X POST https://api.katzilla.dev/agents/hazards/actions/usgs-earthquakes \
  -H "X-API-Key: kz_your_key_here" \
  -H "Content-Type: application/json" \
  -d '{"minMagnitude": 5, "limit": 10}'

Public endpoints (no auth): /health, /status, /openapi.json, /agents, /agents/tools, /agents/datasets.

Data coverage

• US federal — congress.gov, SEC EDGAR, Federal Register, Regulations.gov, USAspending, FEC, govinfo, State Department
• US case law — CourtListener (opinions at every level)
• US health — FDA recalls / adverse events / devices, NIH ClinicalTrials.gov, CMS, CDC
• US hazards — USGS earthquakes & water, NWS alerts, FEMA disasters, NASA FIRMS wildfires
• Economics — BLS, FRED, BEA, Census ACS, Treasury Fiscal Data
• International portals — UK, France, Germany, Canada, Australia, Brazil, Ireland, Spain, Italy, Poland, and more
• International bodies — Eurostat, ECB, WHO, OECD, IMF, World Bank, UN Comtrade, SIPRI
• …plus crypto, space, demographics, energy, transport, agriculture.

Full source list at https://katzilla.dev.

Repository layout

Monorepo (pnpm workspaces).

Package	Purpose
packages/api	Fastify 5 REST API server
packages/app	React 19 + Vite SPA frontend
packages/sdk	Official TypeScript SDK (npm)
packages/python-sdk	Official Python SDK
packages/mcp	Standalone MCP server (npm)
packages/core	Shared types, schemas, utilities
packages/agents/*	One package per data-source category

Development

pnpm install
pnpm build          # build all packages
pnpm dev            # dev mode (api + app in parallel)
pnpm dev:api        # api only
pnpm dev:app        # frontend only
pnpm typecheck      # typecheck all packages
pnpm test:e2e       # Playwright E2E tests (needs app on :5173)

Required env vars: DATABASE_URL, JWT_SECRET, CREDENTIAL_ENCRYPT_KEY. Data-source keys (optional, BYOK): DATA_GOV_API_KEY, FRED_API_KEY, BLS_API_KEY, etc. See .env.example.

Links

• Site & dashboard — https://katzilla.dev
• API docs — https://api.katzilla.dev/openapi.json
• Issues — https://github.com/codeislaw101/katzilla/issues

License

MIT