GovInfo API

The GovInfo API requires an api.data.gov key. You can sign up for a key at https://www.govinfo.gov/api-signup.

Once you have a key, you can include it in your requests. A common method is to pass it as a query parameter named api_key. You can also use the 'Authorize' feature on the interactive OpenAPI/swagger documentation page to enter your key for testing.

https://api.govinfo.gov/collections?api_key=DEMO_KEY

To allow an LLM client to access GovInfo content and metadata via the Model Context Protocol (MCP), you must add the GovInfo MCP server to your client's configuration file (typically mcp.json).

You will need a GovInfo API key. You can sign up for one at govinfo.gov/api-signup or use an existing api.data.gov key.

Add the following configuration to your mcp.json file, replacing YOUR_GOVINFO_API_KEY with your actual key.

{
  "mcpServers": {
    "mcp-govinfo": {
      "url": "https://api.govinfo.gov/mcp",
      "headers": {
        "x-api-key": "YOUR_GOVINFO_API_KEY"
      }
    }
  }
}

When requesting a ZIP or MODS file that is not currently in the cache, the API may return an HTTP 503 response. This indicates the system is currently generating the file.

Action required:

1. Check the Retry-After header in the response. It typically contains a value of 30 (seconds).
2. Wait for the specified number of seconds before retrying the request.
3. If the file is still being generated, you may receive another 503 with a new Retry-After header.

Example error body:

{"message":"Generating ZIP file. Please retry your request again after 30 seconds"}

An HTTP 401 error with the message API_KEY_MISSING indicates that the request did not include a valid API key.

Solutions:

• Use the DEMO_KEY for temporary testing (note that it has lower rate limits).
• Obtain a regular API key to access higher limits and other Federal APIs via api.data.gov.

The GovInfo API implements rate limiting to prevent resource exhaustion. If you exceed the limit, the API will return a 429 status code.

To monitor your usage, inspect the following response headers:

• X-RateLimit-Limit: The total number of requests allowed in the current window.
• X-RateLimit-Remaining: The number of requests remaining in the current window.

Note: The DEMO_KEY has a lower limit than regular user keys.

X-RateLimit-Limit: 40
X-RateLimit-Remaining: 39

The searchGovInfo tool is a discovery tool used to find official GovInfo content and metadata.

When called, it returns basic information for matching results, including:

• Title of the result
• Unique identifiers
• Official publication dates
• Last system update times
• A link to the associated GovInfo details page
• A brief teaser of the content

A Granule Summary provides basic metadata and links to all available content and metadata formats (including ZIP files) for a specific granule. This is similar to the Package Summary but operates at the individual granule level.

Example endpoints:

• Congressional Record (CREC): https://api.govinfo.gov/packages/CREC-2018-07-10/granules/CREC-2018-07-10-pt1-PgD782/summary?api_key=DEMO_KEY
• Federal Register (FR): https://api.govinfo.gov/packages/FR-2018-04-12/granules/2018-07777/summary?api_key=DEMO_KEY

The Related Service identifies and retrieves metadata about content related to a specific access ID.

Pattern: https://api.govinfo.gov/related/{accessId}

Example: https://api.govinfo.gov/related/BILLS-116hr748enr?api_key=DEMO_KEY

This returns a list of relationships that can be followed to retrieve specific documents.

Common Relationships:

• From BILLS/PLAW: Related Bill Versions, Bill History, Presidential Signing Statements, Public/Private Laws, Committee Prints, Reports, U.S. Code References, and Statutes at Large References.
• From FR (Federal Register): Related FR documents by RIN (Regulation Identifier Number) and CFR Citations.
• From CHRG (Hearings): Related Hearings (parts or errata).

The Search Service allows programmatic requests against the GovInfo search engine using a POST request. This returns results similar to the GovInfo web interface.

Sample Request:

curl --location 'https://api.govinfo.gov/search' \
--data '{
    "query":"collection:(USCOURTS) and naturesuit:(Securities, Commodities, Exchange) courttype:appellate",
    "pageSize":"100",
    "offsetMark":"*",
    "sorts":[
        {
            "field":"score",
            "sortOrder":"DESC"
        }
    ]
}'

To get a JSON list of all collections available in the system, perform a GET request to the /collections endpoint. The response includes collectionCode, collectionName, packageCount, and granuleCount (where applicable).

https://api.govinfo.gov/collections?api_key=DEMO_KEY