eCFR by 1102tools

Compare the text of a CFR section at two different dates. Useful for understanding what changed in a regulatory amendment. Returns 'changes' (each paragraph that was added, removed or changed, with its before and after text; also heading, table and pending-amendment-link changes), 'identical' when nothing differs, and the parsed text at both dates side by side. When both texts together are too long to send, the full texts are left out (texts_omitted) and 'changes' is kept. changes_only=True leaves the full texts out every time: the short answer to "what changed". Dates must be in YYYY-MM-DD format. Historical snapshot availability varies by title and section, including some dates before 2017. Use get_version_history to discover dates. Both dates must not exceed the title's up_to_date_as_of value. This tool always returns the section-level XML parsed -- pass a small section_id like '15.305', not a whole part. Whole-part comparisons can exceed 100 KB per side.

compare_versions

Find a term's definition in FAR 2.101, the FAR's main definitions section. Returns each matching definition whole (the defining paragraph and every sub-paragraph under it), first, marked kind='definition'. Matching ignores case, hyphens, spacing, plurals, a trailing "means", and the acronym 2.101 puts in a name, so 'service-disabled veteran-owned small business concern', 'SDVOSB concern', 'COTS', 'commercial services' and 'contract means' all find their definitions. Other 2.101 paragraphs that use the term (whole words only) follow as kind='mention', each naming the definition it sits in. When 2.101 doesn't define the term, the tool searches the rest of the FAR (chapter 1), then the DFARS (chapter 2), for "<term>" means and returns where it is defined, with the definition text, under defined_elsewhere (for example 19.001 and 52.219-14 for 'similarly situated entity'; 204.7301 for 'covered defense information'), plus did_you_mean suggestions from 2.101. term must be at least 3 characters. max_matches caps the number of matches returned (default 20, max 100); definitions are never cut, and truncated says whether mentions were left out.

find_far_definition

Find CFR sections changed since a given date, removals included. Built on eCFR's version history: every version issued on or after since_date, newest first. Each change says whether the section was amended, removed (change='removed'), or re-issued with no text change (substantive=false). 'summary' counts each kind. A section changed twice appears twice. since_date must be in YYYY-MM-DD format. Filter with title (default 48), chapter (Title 48: 1 = FAR, 2 = DFARS, 99 = CAS) or part. per_page (default 100, max 5000) and page step through long lists; total_pages says how many pages there are. Common pattern: find FAR changes since a specific date to check for regulatory updates that might affect ongoing acquisitions.

find_recent_changes

Get the breadcrumb hierarchy path for a section, part, or appendix. Returns ancestors from title down to the target node: title > chapter > subchapter > part > subpart > section. Useful for understanding where a section sits in the CFR hierarchy and what regulation it belongs to. part/subpart/section/appendix accept int or string. The answer says which date it describes.

get_ancestry

Get the full text of a CFR section, subpart, part, or appendix. Returns parsed clean text by default: heading, paragraphs and citations, plus tables, notes, examples, images, pending_amendments and editorial_notes when present. Tables, notes and examples are numbered, and a marker like "[See table 1: ...]" sits in the paragraphs where each appears. [fn N] marks a footnote reference. pending_amendments means eCFR links a published amendment that may not be in effect yet. A subpart, part or appendix request returns one object per section under 'sections', each with its own section number and heading. Set raw_xml=True to get the original XML instead. Answers longer than about 60,000 characters come in pages: the reply says page and total_pages, and page=2 (and so on) returns the rest. Specify the narrowest scope possible to keep responses manageable: - section='15.305' for a single FAR section - subpart='15.3' for a subpart - part='15' for an entire part (can be large) - chapter='1' for an entire chapter (often >1 MB, avoid) - appendix='Appendix A to Chapter 2' (with chapter='2') for a DFARS appendix Date auto-resolves to the latest available if not provided. Do NOT use today's date directly -- eCFR lags 1-2 business days and today often 404s. Title 48 = FAR/DFARS. Chapter 1 = FAR (Parts 1-99), Chapter 2 = DFARS (Parts 200-299). Other chapters = agency FAR supplements (GSAR, VAAR, HSAR, etc.). For DFARS clauses, use chapter='2' (e.g., section='252.227-7014'). part/subpart/section accept int or string. Common prefix mistakes like section='FAR 15.305' or '48 CFR 15.305' are stripped automatically, and trailing paragraph cites like section='15.305(a)(2)' resolve to the base section '15.305'.

get_cfr_content

Get the hierarchical table of contents for a CFR title or subset. Returns a nested tree of titles, chapters, parts, subparts, and sections with identifiers, descriptions, and byte sizes, plus the date it describes. IMPORTANT: Does NOT support section-level filtering (returns 400). Use part or subpart, then walk the children to find sections. Common patterns: - part='15' for FAR Part 15 structure - subpart='15.3' for just that subpart's sections - chapter='1', depth=2 for the FAR's subchapters and parts only - appendix='Appendix A to Part 200' with part='200' (title 2) for one appendix depth keeps that many levels below the node asked for (part='19', depth=1 gives Part 19's subparts); deeper levels are replaced by 'children_omitted' (how many there were). For the sections of one part, list_sections_in_part is shorter. A tree too large to send at once (a whole chapter is about 1 MB) is cut to the deepest depth that fits, and 'note' says so. subchapter needs chapter in Title 48 (each chapter has its own subchapter A, B, ...). part/subpart/chapter/appendix accept int or string.

get_cfr_structure

Get editorial corrections for a CFR title, newest first. Returns corrections with CFR references, corrective actions, error dates, and FR citations, sorted by the date the error was corrected, newest first. Useful for checking whether a section's current text has been corrected since its last amendment. section (e.g. '52.204-21'), part (e.g. '52') or chapter (e.g. '2' for the DFARS) keeps only corrections that touch it. since_year keeps corrections with year >= since_year. limit caps how many are returned (default 50, max 1000); truncated says whether older ones were left out. Title 48 has ~280 corrections since 2005.

get_corrections

Get the most recent available date for a CFR title. CRITICAL: eCFR lags 1-2 business days behind the Federal Register. Using today's date on versioner endpoints causes 404 errors. Call this first to get the safe date, then pass it to other tools. Default title 48 = Federal Acquisition Regulations System (FAR, DFARS, and all agency supplements). Other common titles: 2 (Grants/Agreements), 5 (Administrative Personnel), 29 (Labor), 41 (Public Contracts). Raises ValueError for titles 1-50 that are reserved (no content).

get_latest_date

Get the version history of a CFR section, subpart, or part. Returns content_versions (each with date, amendment_date, issue_date, identifier, name, substantive and removed), every version eCFR lists: all of eCFR's pages are read, so Part 52's 2,264 versions are all there. Versions are grouped by section, oldest first. since_date/until_date (YYYY-MM-DD) keep versions dated in that range. per_page (default 200, max 1000) and page step through long histories; total_count and total_pages say how many there are. 'substantive' is eCFR's flag: true when the version's text differs from the one before, including editorial edits such as citation fixes and the "Link to an amendment published at ..." notice eCFR adds when a rule is published; false when re-issued with no text change. To see what actually changed, use compare_versions on the dates. 'removed' true means the section was removed on that date. Version metadata and text snapshots may include dates before 2017. Availability varies by title and section. Use the returned history dates for reads or comparisons; a missing old snapshot produces an availability error. A 2017-01-01 baseline often means unchanged since before 2017. part/subpart/section accept int or string.

get_version_history

List all agencies with their CFR title and chapter references. Returns agency names, slugs, and which CFR titles/chapters they own. Useful for finding which chapter corresponds to an agency's FAR supplement. summary_only (default True) strips the `children` and most of `cfr_references` to keep the response compact (~20 KB vs ~100 KB). References owned by child agencies are merged into the parent row, so chapter lookups like DFARS (chapter 2, on a DoD child agency) still work in summary mode. Set False for the full raw payload including children.

list_agencies