ToolMint Federal Register JSON

Search and fetch US Federal Register documents (public API). Includes open-comment fields.

Routes and prices

Route	Price	What it does	Parameters (* required)
`GET /search`	$0.005	Search Federal Register documents	`q`*, `per_page`, `page`, `type`
`GET /comments`	$0.005	FR docs with open comment periods	`q`*, `per_page`
`GET /doc`	$0.005	Fetch one FR document by document_number	`document_number`*
`GET /doc/{number}`	$0.005	Fetch one FR document by path	`number`*
`GET /agency`	$0.005	FR docs by agency slug	`agency`*, `per_page`

Free routes: /, /health, /openapi.json, /.well-known/x402.

Try it

Call it with no payment. You get 402 and a base64 PAYMENT-REQUIRED header. Decoded, it looks like this (captured from the live tool on 2026-10-31 17:32 UTC):

curl -i "https://toolmint-federal-register-json.toolmint.workers.dev/search?q=ai"

{
  "x402Version": 2,
  "accepts": [
    {
      "scheme": "exact",
      "network": "eip155:8453",
      "amount": "5000",
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "payTo": "0xfbF7413bcB3a604936775C96FDbe0b0C9c9E37F5",
      "maxTimeoutSeconds": 300,
      "extra": {
        "name": "USD Coin",
        "version": "2"
      }
    }
  ],
  "resource": {
    "url": "https://toolmint-federal-register-json.toolmint.workers.dev/search?q=ai",
    "description": "Search Federal Register documents (q, per_page, page, type)",
    "mimeType": "application/json",
    "serviceName": "ToolMint Federal Register",
    "tags": [
      "federal-register",
      "gov",
      "regulation",
      "public-data",
      "toolmint"
    ],
    "iconUrl": "https://toolmint.toolmint.workers.dev/icon.png"
  }
}

amount is in USDC base units (6 decimals): 5000 = $0.005. Repeat the same request with a PAYMENT-SIGNATURE header from any x402 client.

What question it answers

"What has the Federal Register published about this topic, newest first?" (/search)
"Which documents on this topic are still open for public comment?" (/comments)
"What are the details and links for document 2026-22174?" (/doc)
"What did this agency publish recently?" (/agency)

When to use it

You need current federal rulemaking items in a flat shape with agency names, dates, links and comment close dates.

When not to use it

Legal research or a legal opinion on relevance. Search is keyword matching by the upstream API.
Full text. You get the abstract, links to the HTML/PDF, and for /doc the link to the full text. The tool does not return the body text itself.
The Federal Register API is free. You pay for the cleaned shape and not building the client.

Example

curl -i "https://toolmint-federal-register-json.toolmint.workers.dev/search?q=accreditation&per_page=1"
# 402 + PAYMENT-REQUIRED. Pay with an x402 client, repeat with PAYMENT-SIGNATURE.

Response after payment (trimmed; document values are from a real sample in the package folder, shape from the Worker code):

{
  "tool": "federal-register-json",
  "version": "0.2.0",
  "query": "accreditation",
  "page": 1,
  "typeFilter": null,
  "count": 42,
  "documents": [
    {
      "documentNumber": "2026-22174",
      "title": "Accreditation, Innovation, and Modernization: ...",
      "type": "Rule",
      "abstract": "The Department revises the existing accrediting agency recognition regulations ...",
      "publicationDate": "2026-10-30",
      "agencies": ["Education Department"],
      "htmlUrl": "https://www.federalregister.gov/documents/2026/10/30/2026-22174/...",
      "pdfUrl": "https://www.govinfo.gov/content/pkg/FR-2026-10-30/pdf/2026-22174.pdf",
      "commentsCloseOn": null,
      "commentUrl": null,
      "dates": null
    }
  ],
  "openCommentCount": 0,
  "source": "federalregister.gov public API",
  "cached": false
}

(count here is illustrative.) /doc returns { tool, version, document, source, cached } where document has the same fields plus topics[], bodyHtmlUrl and rawTextUrl. /comments returns mode: "open_comments"; /agency returns agency instead of query.

Data source and licence

Source: the Federal Register public API at federalregister.gov. Federal Register content is a US government work and is generally public domain. Check the source's terms if you redistribute. Not endorsed by the Office of the Federal Register or NARA.

Freshness and limits

Cached in memory on one server instance: searches and agency lists 6 hours, open-comment searches 3 hours, single documents 24 hours. cached tells you if it was a cache hit. There is no fetchedAt field.
At most 20 documents per call. Paging works on /search only.
/comments is newest first, not sorted by close date.
type and agency values are not checked by this tool; what a wrong value returns is up to the upstream API.
If it runs out, paid calls fail and are not charged.

Errors are not charged

Payment settles only on a successful answer. Any response with status 400 or higher (bad input, not found, upstream failure) is never settled.