CFR Part Watch API: Federal rules and proposed rules amending a specific CFR title and part — Federal Register

Name: CFR Part Watch API: Federal rules and proposed rules amending a specific CFR title and part — Federal Register
Creator: AnswerPool
License: https://www.usa.gov/government-works

Federal rules and proposed rules amending a specific CFR title and part (e.g. 17 CFR 240), newest first with deadline flags. Watch the exact provisions you are subject to instead of whole agencies or topics.

$0.02 per call — pay with prepaid card credits (Authorization: Bearer ck_live_…, packs from $1) or with USDC over x402: call it, get 402 with the price, retry signed. Failed calls are never charged.

How do you call it?

GET /v1/regs/cfr — product id reg_cfr_watch. Over MCP, call answerpool_get with product_id=reg_cfr_watch.

curl "https://answerpool.io/v1/regs/cfr?cfr_title=17&cfr_part=240"

# with a prepaid credit key
curl -H "Authorization: Bearer ck_live_..." "https://answerpool.io/v1/regs/cfr?cfr_title=17&cfr_part=240"

Live call: https://answerpool.io/v1/regs/cfr?cfr_title=17&cfr_part=240 · JSON sample: /v1/samples/reg_cfr_watch

What does the answer look like?

A representative response, the same static sample served at /v1/samples/reg_cfr_watch.

`as_of`	2026-09-02T14:00:00Z
`total_matching`	1
`count`	1
`refresh_after`	2026-09-18T00:00:00.000Z

`documents`

document_number	title	type	action	agencies	publication_date	effective_on	comments_close_on	significant	abstract	docket_ids	regulation_id_numbers
2026-12341	Cybersecurity Risk Management Rule	Rule	Final rule.	Securities and Exchange Commission	2026-08-30	2026-09-12	—	true	Requires registrants to disclose material cybersecurity incidents.	SEC-2026-001	3235-AN00

The same sample as raw JSON

{
 "as_of": "2026-09-02T14:00:00Z",
 "total_matching": 1,
 "count": 1,
 "documents": [
  {
   "document_number": "2026-12341",
   "title": "Cybersecurity Risk Management Rule",
   "type": "Rule",
   "action": "Final rule.",
   "agencies": [
    "Securities and Exchange Commission"
   ],
   "publication_date": "2026-08-30",
   "effective_on": "2026-09-12",
   "comments_close_on": null,
   "significant": true,
   "abstract": "Requires registrants to disclose material cybersecurity incidents.",
   "docket_ids": [
    "SEC-2026-001"
   ],
   "regulation_id_numbers": [
    "3235-AN00"
   ],
   "cfr_references": [
    "17 CFR 240"
   ],
   "topics": [
    "Securities"
   ],
   "url": "https://www.federalregister.gov/d/2026-12341",
   "flags": [
    "significant",
    "effective_soon",
    "final_rule_pending_effect"
   ],
   "days_to_comment_close": null,
   "days_to_effective": 10
  }
 ],
 "refresh_after": "2026-09-18T00:00:00.000Z"
}

How fresh is it, and where does the data come from?

The fastest source behind this answer can change daily, so every response carries a refresh_after timestamp — right now it would be 2026-09-18T00:00:00.000Z. Schedule the next call on that value rather than on a guess.

Federal Register (US federal public domain) — upstream: https://www.federalregister.gov/api/v1

Method version 0.1.0 · serving cache 1 day · every response carries a result_id you can resolve at /v1/provenance.

When should you use it?

Your obligations map to known CFR parts and you react only to those.

What you skip building

CFR citation query syntax
cross-referencing affected parts

When should you not use it?

Exploratory topic tracking — use search; whole-agency views — use the agency feed.

Where else can you find this?

Catalog entry (JSON, free)
OpenAPI schema — input and output types, prices, the 402 flow
llms.txt — every product in one plain-text document