All servers · Government & law · Research & knowledge

eCFR

com.1102tools/ecfr-mcp · v1.1.13

Measured by MCP Station

Description written by the publisher, not verified

Electronic Code of Federal Regulations including FAR, DFARS, and agency supplements. 13 tools.

Connect

claude mcp add --transport http ecfr-mcp https://ecfr.1102tools.com/mcp

{
  "mcpServers": {
    "ecfr-mcp": {
      "url": "https://ecfr.1102tools.com/mcp"
    }
  }
}

Tools as reported by the server

• get_latest_date
  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 Sy
• get_cfr_content
  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
• get_cfr_structure
  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 subpar
• get_version_history
  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 sec
• get_ancestry
  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/sectio
• search_cfr
  Full-text search across the Code of Federal Regulations. Returns matching sections with excerpts, headings, scores, and hierarchy. current_only=True (default) returns only text in effect now. eCFR's own "current" index still lists some superseded and removed versions, so each hit is checked against
• list_agencies
  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 r
• get_corrections
  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 amendm
• lookup_far_clause
  Convenience tool: look up the current text of a FAR, DFARS or FAR supplement section or clause. Pass a section identifier like '15.305', '52.212-4', '2.101', 'DFARS 252.204-7012' or '552.238-81'. The chapter comes from the number (52.x = FAR, 252.x = DFARS, 552.x = GSAR, 852.x = VAAR, 1852.x = NFS,
• compare_versions
  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 n
• list_sections_in_part
  List all sections and appendices in a CFR part with their headings. Returns 'sections' in order, each {identifier, heading}, with type='appendix' on appendices (2 CFR 200's Appendix I-XII, for example) and reserved=true on reserved sections, plus 'subparts' (each with its heading, section_count and
• find_far_definition
  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 pu
• find_recent_changes
  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' c

Tool changes

• 2026-10-24: get_latest_date, get_cfr_content, get_cfr_structure, get_version_history, get_ancestry, search_cfr, list_agencies, get_corrections, lookup_far_clause, compare_versions, list_sections_in_part, find_far_definition
• 2026-10-22: get_latest_date, get_cfr_content, get_cfr_structure, get_version_history, get_ancestry, search_cfr, list_agencies, get_corrections, lookup_far_clause, compare_versions, list_sections_in_part, find_far_definition

Repository · Website · JSON · Text for agents · Registry updated 2026-10-23