API Keys
21 APIs work with no key at all. The rest use free keys — most take under a minute to get.
Setting Keys
Two options
Option 1 — .env file (recommended for local development):
Create a .env file in your project root:
DATA_GOV_API_KEY=your_key_here
FRED_API_KEY=your_key_hereOption 2 — env block in MCP config (recommended for VS Code / Claude Desktop):
Add keys directly in your MCP client config as shown in Getting Started.
Key Reference
| Key | APIs | Get it |
|---|---|---|
BEA_API_KEY | Bureau of Economic Analysis | Sign up |
BLS_API_KEY | Bureau of Labor Statistics | Sign up |
CENSUS_API_KEY | Census Bureau | Sign up |
DATA_GOV_API_KEY | College Scorecard, Congress.gov, FBI Crime Data Explorer, FDA (OpenFDA), OpenFEC (Federal Election Commission), GovInfo, NREL (Clean Energy), Regulations.gov, USDA FoodData Central | Sign up |
DOL_API_KEY | DOL (Department of Labor) | Sign up |
EIA_API_KEY | Energy Information Administration | Sign up |
AQS_API_KEY | EPA Air Quality System (AQS) | Sign up |
AQS_EMAIL | EPA Air Quality System (AQS) | Sign up |
FRED_API_KEY | FRED (Federal Reserve Economic Data) | Sign up |
HUD_USER_TOKEN | HUD | Sign up |
NOAA_API_KEY | NOAA Climate Data Online | Sign up |
USDA_NASS_API_KEY | USDA NASS QuickStats | Sign up |
USPTO_API_KEY | USPTO Open Data Portal | Sign up |
No-Key APIs (21)
These APIs work immediately — no signup required:
BTS (Bureau of Transportation Statistics), CDC Health Data, CFPB (Consumer Financial Protection Bureau), ClinicalTrials.gov, CMS, DOJ News, EPA (Environmental Protection Agency), FDIC (Federal Deposit Insurance Corporation), Federal Register, FEMA, GSA CALC+ Ceiling Rates, NAEP (Nation's Report Card), NHTSA, NIH RePORTER, Open Payments (Sunshine Act), SEC EDGAR, Senate Lobbying Disclosures, U.S. Treasury Fiscal Data, USAspending, USGS (U.S. Geological Survey), World Bank
Optional keys for higher rate limits
Some no-key APIs accept an optional DATA_GOV_API_KEY for higher rate limits. If you already have one set for other modules (Congress, FBI, FEC, etc.), these APIs will automatically use it:
- FDA (OpenFDA) — 240 req/min without key, 120K req/day with key
- CDC — 1,000 req/hour without app token (token support not yet implemented)
You don't need to do anything extra — if the key is in your environment, it's used automatically.