One call answers "what does 21 CFR 101.9 say today, when did it last change, and which Federal Register rule changed it?": the section as plain text from the eCFR (as in force today or on any date since 2017), its amendment history, and the final rules behind each change. It also lists what changed in a CFR part since a date ("15 CFR 744 this week") and returns Federal Register documents by number or search. Built for AI agents doing regulatory, compliance and export-control work, and for people who want a sourced answer without learning two APIs.

Price$0.005 per section, $0.002 per document

DomainCompliance & law

Call itApify API, MCP or HTTP API

Pricing (pay per event): $0.005 per CFR section returned (section), $0.002 per Federal Register document returned (document). A citation that can't be read, a section that doesn't exist or an empty result fails or ends in seconds and costs nothing.

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Questions agents ask

“What changed in the Export Administration Regulations part 744 since August, and which Federal Register notices did it? Link the sources.”

What you get

Field	Type	Meaning
`schema_version`	string	Output schema version.
`record_type`	string	"cfr_section" (a CFR section or appendix as of a date) or "fr_document" (a Federal Register document).
`query`	string \| null	The citation, document number or search as understood, e.g. "21 CFR 101.9".
`citation`	string \| null	cfr_section: the unit's CFR citation, e.g. "21 CFR 101.9". fr_document: the Federal Register citation (volume FR page), e.g. "91 FR 54658".
`cfr_title`	integer	cfr_section: CFR title number (1-50), e.g. 21.
`cfr_title_name`	string \| null	cfr_section: name of the CFR title, e.g. "Food and Drugs".
`part`	string \| null	cfr_section: CFR part, e.g. "101".
`subpart`	string \| null	cfr_section: subpart letter, e.g. "A"; null when the part has none or for appendices.
`section`	string \| null	cfr_section: section number ("101.9") or appendix name ("Supplement No. 4 to Part 744").
`unit_type`	string \| null	cfr_section: "section" or "appendix".
`heading`	string \| null	cfr_section: the heading as printed, e.g. "§ 101.9 Nutrition labeling of food.".
`as_of`	string \| null	cfr_section: the date (YYYY-MM-DD) the text is in force for: asOf, capped at the eCFR's latest data.
`text`	string \| null	cfr_section: plain text as in force on as_of, one line per paragraph ("(a) ...", "(1) ..."), tables as "cell \| cell" rows; cut at maxTextChars. Null when the unit was removed.
`text_chars`	integer \| null	cfr_section: length of text in characters (after any cut).
`text_truncated`	boolean \| null	cfr_section: true when text was cut at maxTextChars.
`source_note`	string \| null	cfr_section: the CFR source note with the Federal Register citation(s) that created the unit, e.g. "[58 FR 2175, Jan. 6, 1993]".
`removed`	boolean \| null	cfr_section: true when the unit was removed from the CFR on or before as_of.
`latest_change_date`	string \| null	cfr_section: date of the newest amendment on or before as_of (YYYY-MM-DD).
`changed_since`	string \| null	cfr_section from a part citation: the since date of the change window; null for a single-section lookup.
`amendments`	array	cfr_section: amendment history from the eCFR versioner, newest first (max 50): {date, substantive, removed, fr_documents}. fr_documents lists final rules affecting this CFR part that took effect (or, failing that, were published) on that date: {document_number, citation, title, type, publication_date, effective_on, url}. They are the likely source of the change, matched by part and date (the Federal Register does not index by section). [] = looked up, none found; null = not looked up (only the 5 newest dates, or the dates inside the since window, are).
`ecfr_up_to_date_as_of`	string \| null	cfr_section: the date through which the eCFR title is current (YYYY-MM-DD).
`source_url`	string \| null	eCFR page of the unit as of as_of (cfr_section), or FederalRegister.gov page of the document (fr_document).
`provided_by`	string	Who compiled this row; cite together with source_url.
`api_url`	string \| null	cfr_section: the eCFR versioner API call the text was read from.
`document_number`	string \| null	fr_document: Federal Register document number, e.g. "2026-17231".
`title`	string \| null	fr_document: document title.
`type`	string \| null	fr_document: "Rule", "Proposed Rule", "Notice" or "Presidential Document".
`action`	string \| null	fr_document: action line, e.g. "Final rule.".
`abstract`	string \| null	fr_document: the summary published with the document.
`dates`	string \| null	fr_document: the DATES paragraph as published, e.g. "This rule is effective August 21, 2026.".
`agencies`	array	fr_document: issuing agencies as FederalRegister.gov names them, e.g. ["Commerce Department", "Industry and Security Bureau"].
`publication_date`	string \| null	fr_document: date published in the Federal Register (YYYY-MM-DD).
`effective_on`	string \| null	fr_document: effective date (YYYY-MM-DD); null when none is given (proposed rules, most notices).
`comments_close_on`	string \| null	fr_document: comment deadline (YYYY-MM-DD); null when not open for comment.
`cfr_references`	array	fr_document: CFR parts the document affects, e.g. ["15 CFR 744"].
`docket_ids`	array	fr_document: agency docket numbers.
`regulation_id_numbers`	array	fr_document: Regulation Identifier Numbers (RIN), e.g. ["0694-AK49"].
`start_page`	integer \| null	fr_document: first Federal Register page.
`end_page`	integer \| null	fr_document: last Federal Register page.
`significant`	boolean \| null	fr_document: whether the rule is marked significant under EO 12866; null when not stated.
`pdf_url`	string \| null	fr_document: the official PDF on govinfo.gov (the legally authentic edition).
`raw_text_url`	string \| null	fr_document: full text as plain text on FederalRegister.gov.
`warnings`	array	Caveats in plain words: text cut, date capped, more results than returned, part-level matching.
`retrieved_at`	string	When the row was made (ISO 8601, UTC).
`duration_seconds`	number	How long the lookup took.

Use with AI agents (MCP)

Add this URL to your MCP client (Claude, Cursor, VS Code, ...) to load the Actor as a tool through the Apify hosted MCP server. It signs you in with OAuth or accepts Authorization: Bearer <APIFY_TOKEN>. It works once the Actor is live on the Apify Store.

https://mcp.apify.com?tools=bosco_labs/us-federal-rules

For “What changed in the Export Administration Regulations part 744 since August, and which Federal Register notices did it? Link the sources.” the agent passes:

{ "citation": "15 CFR 744", "since": "2026-08-01" }

small JSON rows (a section is typically 5-25 KB with the default text cap), stable snake_case fields, ISO dates, null for unknown, a source link per row and per linked rule. A unit whose text eCFR fails to send in a part listing comes back with text: null, a warning and no charge. warnings says in plain words when text was cut, a date was capped at the eCFR's latest data, or more results matched than were returned. A section lookup takes 1-2 seconds after start-up (measured 1.6 s for 21 CFR 101.9); a part with changes 2-7 seconds for a few units (the Entity List alone is 1.4 million characters of XML), up to about a minute for 25 units, which are downloaded two at a time to stay within eCFR's limits.

Or call the Apify API: POST https://api.apify.com/v2/acts/bosco_labs~us-federal-rules/run-sync-get-dataset-items with the input as JSON body. Cost: $0.005 per section, $0.002 per document.

HTTP API

Also on the Bosco Labs HTTP API (beta, test mode): same input and same rows as the Actor, $0.001 per unit: a CFR section with text = 5 units ($0.005), a Federal Register document = 2 ($0.002); rows without text are free from prepaid credits (max 10 CFR units or 50 documents per call). Get a key with a $0.50 free trial; see prices and limits.

curl https://api.boscolabs.dev/v1/us-federal-rules \
  -H "Authorization: Bearer $BOSCO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"citation": "15 CFR 744", "since": "2026-08-01"}'

Input fields

Field	Type	Meaning
`citation`	string	A CFR section, part or appendix: "21 CFR 101.9", "17 CFR 240.10b-5", "48 CFR 52.212-4", "15 CFR 744 Supplement No. 4", or an eCFR link ("https://www.ecfr.gov/current/title-21/section-101.9"). A section or appendix returns one row: its text as in force on asOf, its amendment history and the Federal Register rules behind each change. A part ("15 CFR 744") returns its sections and appendices changed since the since date. Together with search, agency or documentType it instead limits Federal Register documents to that CFR part. Empty = no CFR lookup. An unreadable citation fails in seconds with examples, at no charge.
`asOf`	string	YYYY-MM-DD, e.g. "2024-01-01": the CFR text in force on that date (eCFR history begins around January 2017). Empty = today (the eCFR's latest data, usually 1-2 days old).
`since`	string	YYYY-MM-DD, e.g. "2026-11-01". With a part citation: list sections changed on or after this date (empty = the last 30 days). With a search: only documents published on or after this date (empty = any date). Ignored for a single section or a document number.
`documentNumber`	string	One Federal Register document by its number, e.g. "2026-17231" (corrections look like "C1-2026-16628"). Returns its citation, type, agencies, dates, the CFR parts it affects and links. Empty = no document lookup. Takes precedence over every other field.
`search`	string	Full-text search of Federal Register documents since 1994, newest first, e.g. "entity list". Combine with agency, documentType, since and citation. Empty = no word filter (agency or documentType alone also search).
`agency`	string	Federal Register search by issuing agency: an acronym ("BIS", "FDA", "EPA", "SEC", "OFAC"), a name ("Bureau of Industry and Security") or a FederalRegister.gov slug ("industry-and-security-bureau"). Empty = all agencies. An unknown name fails with suggestions, at no charge.
`documentType`	string	Federal Register search by type: RULE (final rules), PRORULE (proposed rules), NOTICE or PRESDOCU (presidential documents). Empty = all types.
`maxResults`	integer	Most rows to return: for a part citation the most recently changed units (max 25 per run, each with its text), for a search the newest documents (max 100). Default 20. One charge per row returned with an answer.
`maxTextChars`	integer	Cap on each section's text in characters, e.g. 20000 (default). Longer text is cut at a line end and flagged with text_truncated and a warning; source_url has the whole text.

Sources, licence and limits

Where does the data come from? Only from the two official APIs of the Office of the Federal Register (National Archives) and the Government Publishing Office: the eCFR versioner API (point-in-time CFR text and version history) and the FederalRegister.gov API (documents since 1994). Both are keyless. The text is converted from XML to plain text and nothing else is changed.

May you resell this? Yes. FederalRegister.gov and eCFR.gov state: "Any person may reproduce or republish any material appearing in any regular or special edition of the Federal Register (1 CFR 2.6). There are no restrictions regarding what is reproduced, who can reproduce it, or where it can be reproduced." Works of the US Government have no copyright (17 U.S.C. 105), and GPO's e-CFR guide says "there are no restrictions on re-use of information in the e-CFR documents". We don't use NARA or OFR seals or CFR logos and don't claim to be an official edition. Sources: About this site, govinfo policies, e-CFR XML guide.

Is the eCFR text the law? It is, in the OFR's words, "authoritative but unofficial". The official CFR is the annual print edition on govinfo.gov, kept current by the daily Federal Register. For legal research, verify against the official editions; each document row links the official govinfo PDF (pdf_url). This is not legal advice.

How exact is the link between a change and a Federal Register rule? The Federal Register indexes documents by CFR part, not section. For each amendment date we list the final rules that affect the same part and took effect (or were published) that day: in practice that is the rule that made the change, but on a busy day it can include a rule that changed a neighbouring section. Each comes with its title and link so an agent can check. Only the 5 newest amendment dates per run are looked up (older ones show fr_documents: null); in a part listing that is each unit's newest change, for the 5 most recent dates. If the Federal Register lookup fails, the row is kept with fr_documents: null and a warning.

How current is it? Live. The eCFR is updated daily and is usually 1-2 days behind the Federal Register (ecfr_up_to_date_as_of); an asOf later than that returns the latest text with a warning. The point-in-time history starts around January 2017; earlier dates fail with the first available date.

Can it diff two versions or return one paragraph? Not yet. A section is returned whole (a citation like 21 CFR 101.9(c)(8) returns all of 101.9 with a warning), and "what changed" is answered by dates and the rules that made the change, not a text diff. Huge appendices such as the Entity List are cut at maxTextChars (raise it up to 500,000).

Which CFR units work? All 50 titles: sections, and appendices or supplements (15 CFR 744 Supplement No. 4, 40 CFR part 60 appendix A-1). Reserved titles fail with a clear message.

Personal data? None is requested. Federal Register documents and CFR appendices can name people or companies (e.g. the Entity List); they are returned only as published.

Content: Office of the Federal Register (National Archives) and US Government Publishing Office, via ecfr.gov and federalregister.gov. Not an official legal edition.

Coming soon to the Apify StoreAsk for early access

US Federal Rules API: CFR text as of a date + Federal Register

Questions agents ask

Example

Input

Output

What you get

Use with AI agents (MCP)

HTTP API

Input fields

Sources, licence and limits