CourtListener

Measured conclusion: Deep-tested. L2 outcome: tools_ok.

MCP for CourtListener: US federal and state opinions, dockets, judges, plus eCFR regulations.

Add to your agent

Copy this into your MCP client config:

{
  "mcpServers": {
    "CourtListener": {
      "url": "https://courtlistener-mcp.vaquill.ai/mcp/",
      "transport": "streamable-http"
    }
  }
}

Measured tools (34)

• status

  Check the status of the CourtListener MCP server. Returns: A dictionary containing server status, system metrics, and service information.

  Hints: read-only not declared · destructive not declared · idempotent not declared · open-world not declared

• search_opinions read-only

  Search case law opinion clusters with nested Opinion documents in CourtListener.

  Parameters:

  • q (required) — string — Search query for full text of opinions
  • court — Court ID filter (e.g., 'scotus', 'ca9')
  • judge — Filter by judge name
  • limit — integer — Max results from this page (upper bound; CL pages ~20)
  • cursor — Pagination cursor from a prior response's next_cursor
  • cited_gt — Minimum number of times opinion has been cited
  • cited_lt — Maximum number of times opinion has been cited
  • order_by — string — Sort by 'score desc', 'dateFiled desc', or 'dateFiled asc'
  • case_name — Filter by case name
  • filed_after — Only show opinions filed after this date (YYYY-MM-DD)
  • filed_before — Only show opinions filed before this date (YYYY-MM-DD)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• search_dockets read-only

  Search federal cases (dockets) from PACER in CourtListener.

  Parameters:

  • q (required) — string — Search query for docket text
  • court — Court ID filter (e.g., 'scotus', 'ca9')
  • limit — integer — Max results from this page (upper bound; CL pages ~20)
  • cursor — Pagination cursor from a prior response's next_cursor
  • order_by — string — Sort by 'score desc', 'dateFiled desc', or 'dateFiled asc'
  • case_name — Filter by case name
  • party_name — Filter by party name
  • docket_number — Specific docket number to search for
  • date_filed_after — Filter dockets filed after this date (YYYY-MM-DD)
  • date_filed_before — Filter dockets filed before this date (YYYY-MM-DD)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• search_dockets_with_documents read-only

  Search federal cases (dockets) with up to three nested documents. If there are more than three matching documents, the more_docs field will be true.

  Parameters:

  • q (required) — string — Search query for federal cases
  • court — Court ID filter (e.g., 'scotus', 'ca9')
  • limit — integer — Max results from this page (upper bound; CL pages ~20)
  • cursor — Pagination cursor from a prior response's next_cursor
  • order_by — string — Sort by 'score desc', 'dateFiled desc', or 'dateFiled asc'
  • case_name — Filter by case name
  • party_name — Filter by party name
  • docket_number — Specific docket number to search for
  • date_filed_after — Filter dockets filed after this date (YYYY-MM-DD)
  • date_filed_before — Filter dockets filed before this date (YYYY-MM-DD)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• search_recap_documents read-only

  Search federal filing documents from PACER in the RECAP archive.

  Parameters:

  • q (required) — string — Search query for RECAP filing documents
  • court — Court ID filter (e.g., 'scotus', 'ca9')
  • limit — integer — Max results from this page (upper bound; CL pages ~20)
  • cursor — Pagination cursor from a prior response's next_cursor
  • order_by — string — Sort by 'score desc', 'dateFiled desc', or 'dateFiled asc'
  • case_name — Filter by case name
  • party_name — Filter by party name
  • filed_after — Filter documents filed after this date (YYYY-MM-DD)
  • filed_before — Filter documents filed before this date (YYYY-MM-DD)
  • docket_number — Specific docket number to search for
  • document_number — Specific document number to search for
  • attachment_number — Specific attachment number to search for

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• search_audio read-only

  Search oral argument audio recordings in CourtListener.

  Parameters:

  • q (required) — string — Search query for oral argument audio
  • court — Court ID filter (e.g., 'scotus', 'ca9')
  • judge — Filter by judge name
  • limit — integer — Max results from this page (upper bound; CL pages ~20)
  • cursor — Pagination cursor from a prior response's next_cursor
  • order_by — string — Sort by 'score desc', 'dateArgued desc', or 'dateArgued asc'
  • case_name — Filter by case name
  • argued_after — Filter arguments after this date (YYYY-MM-DD)
  • argued_before — Filter arguments before this date (YYYY-MM-DD)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• search_people read-only

  Search judges and legal professionals in the CourtListener database.

  Parameters:

  • q (required) — string — Search query for judges and legal professionals
  • name — Filter by person's name
  • limit — integer — Max results from this page (upper bound; CL pages ~20)
  • cursor — Pagination cursor from a prior response's next_cursor
  • school — Filter by school attended
  • order_by — string — Sort by 'score desc' or 'name asc'
  • appointed_by — Filter by appointing authority
  • position_type — Filter by position type (e.g., 'jud' for judge)
  • selection_method — Filter by selection method
  • political_affiliation — Filter by political affiliation

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• get_opinion read-only

  Get a specific court opinion by ID from CourtListener.

  Parameters:

  • opinion_id (required) — string — The opinion ID to retrieve

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• get_docket read-only

  Get a specific court docket by ID from CourtListener.

  Parameters:

  • docket_id (required) — string — The docket ID to retrieve

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• get_audio read-only

  Get oral argument audio information by ID from CourtListener.

  Parameters:

  • audio_id (required) — string — The audio recording ID to retrieve

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• get_cluster read-only

  Get an opinion cluster by ID from CourtListener.

  Parameters:

  • cluster_id (required) — string — The opinion cluster ID to retrieve

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• get_person read-only

  Get judge or legal professional information by ID from CourtListener.

  Parameters:

  • person_id (required) — string — The person (judge) ID to retrieve

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• get_court read-only

  Get court information by ID from CourtListener.

  Parameters:

  • court_id (required) — string — The court ID to retrieve (e.g., 'scotus', 'ca9')

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• citation_lookup_citation read-only

  Look up a legal citation to find the opinion it references in CourtListener. This tool accepts various citation formats including: - U.S. Reporter citations (e.g., "410 U.S. 113") - Federal Reporter citations (e.g., "123 F.3d 456") - WestLaw citations (e.g., "2023 WL 12345") - State reporter citations

  Parameters:

  • citation (required) — string — The citation to look up (e.g., '410 U.S. 113', '2023 WL 12345')

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• citation_batch_lookup_citations read-only

  Look up multiple legal citations in a single request. This is more efficient than making individual requests for each citation. Accepts up to 100 citations at once.

  Parameters:

  • citations (required) — array — List of citations to look up (max 100)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• citation_verify_citation_format read-only

  Verify if a citation string is in a valid format using citeurl's advanced parsing. This tool performs validation using citeurl's comprehensive citation templates to check if a citation appears to be in a recognized legal citation format. This is much more accurate than simple regex matching. Returns information about the citation format and any detected issues.

  Parameters:

  • citation (required) — string — The citation to verify

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world no

• citation_parse_citation_with_citeurl read-only

  Parse a legal citation using citeurl's advanced citation recognition. This tool uses the citeurl library to parse legal citations and extract structured information including tokens, normalized format, and URL generation. Returns detailed information about the citation including: - Recognized citation format and source - Extracted tokens (volume, reporter, page, etc.) - Generated URL if available - Normalized citation text

  Parameters:

  • citation (required) — string — The citation to parse (e.g., '410 U.S. 113', '42 USC § 1988')
  • broad — boolean — Use broad matching for more flexible parsing

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world no

• citation_extract_citations_from_text read-only

  Extract all legal citations from a block of text using citeurl. This tool finds and parses all legal citations within a given text, including both long-form and short-form citations (like 'id.' references).

  Parameters:

  • text (required) — string — Text containing legal citations to extract

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world no

• citation_enhanced_citation_lookup read-only

  Enhanced citation lookup combining citeurl parsing with CourtListener data. This tool first uses citeurl to parse and validate the citation format, then optionally queries the CourtListener API for additional case information.

  Parameters:

  • citation (required) — string — The citation to look up and analyze
  • include_courtlistener — boolean — Whether to also perform CourtListener API lookup

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_list_titles read-only

  List all 50 CFR titles with their latest amended/issue dates and status.

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_title_versions read-only

  List the available content versions (issue dates) for one CFR title.

  Parameters:

  • title (required) — integer — CFR title number (1-50)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_title_structure read-only

  Get the full hierarchical structure (title -> section) of a CFR title on a date.

  Parameters:

  • title (required) — integer — CFR title number (1-50)
  • date (required) — string — Snapshot date (YYYY-MM-DD)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_ancestry read-only

  Get the ancestry chain (title -> ... -> node) for a CFR node on a date.

  Parameters:

  • title (required) — integer — CFR title number (1-50)
  • date (required) — string — Snapshot date (YYYY-MM-DD)
  • part — Restrict to a part, e.g. '75'
  • section — Restrict to a section, e.g. '75.1'

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_source_xml read-only

  Fetch the source regulation TEXT (XML) for a CFR node on a snapshot date. Pass a part or section to scope the request. Fetching an entire large title at once can time out on the eCFR side, so narrowing is strongly recommended. Returns the raw XML under ``content_xml``.

  Parameters:

  • title (required) — integer — CFR title number (1-50)
  • date (required) — string — Snapshot date (YYYY-MM-DD)
  • part — Part to fetch, e.g. '75'. STRONGLY recommended: whole-title fetches can time out.
  • chapter — Chapter, e.g. 'I'
  • section — Section, e.g. '75.1'
  • subpart — Subpart, e.g. 'C'
  • appendix — Appendix identifier
  • subtitle — Subtitle, e.g. 'A'
  • subchapter — Subchapter, e.g. 'B'

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_list_agencies read-only

  List all agencies that appear in the CFR, with their title/chapter references.

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_list_all_corrections read-only

  List CFR corrections, optionally filtered by title and/or effective date.

  Parameters:

  • date — Corrections in effect on this date (YYYY-MM-DD)
  • title — Restrict to a CFR title number

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_list_corrections_by_title read-only

  List all corrections for a single CFR title.

  Parameters:

  • title (required) — integer — CFR title number (1-50)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_search_regulations read-only

  Full-text search over federal regulations, returning matching sections with hierarchy.

  Parameters:

  • query (required) — string — Full-text search query over the CFR
  • date — Search the CFR as of this date (YYYY-MM-DD)
  • page — integer — Page number
  • order — Sort order: 'relevance', 'hierarchy', 'newest_first', 'oldest_first'
  • title — Restrict to a CFR title number
  • per_page — integer — Results per page (max 20)
  • agency_slugs — Restrict to one or more agency slugs (from list_agencies)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_search_count read-only

  Get the total number of CFR sections matching a search query.

  Parameters:

  • query (required) — string — Full-text search query over the CFR
  • date — As-of date (YYYY-MM-DD)
  • title — Restrict to a title
  • agency_slugs — Restrict to agency slugs

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_search_summary read-only

  Get summary details (counts + metadata) for a CFR search query.

  Parameters:

  • query (required) — string — Full-text search query over the CFR
  • date — As-of date (YYYY-MM-DD)
  • title — Restrict to a title
  • agency_slugs — Restrict to agency slugs

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_title_search_counts read-only

  Get search result counts broken down by CFR title.

  Parameters:

  • query (required) — string — Full-text search query over the CFR
  • date — As-of date (YYYY-MM-DD)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_daily_search_counts read-only

  Get search result counts broken down by date (daily histogram).

  Parameters:

  • query (required) — string — Full-text search query over the CFR
  • date — As-of date (YYYY-MM-DD)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_hierarchy_search_counts read-only

  Get search result counts distributed across the CFR hierarchy.

  Parameters:

  • query (required) — string — Full-text search query over the CFR
  • date — As-of date (YYYY-MM-DD)

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

• ecfr_get_search_suggestions read-only

  Get search-term suggestions for a partial CFR query.

  Parameters:

  • query (required) — string — Partial query to get suggestions for

  Hints: read-only yes · destructive not declared · idempotent not declared · open-world yes

Repository

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