DingDuff
ClaudecommunityFree legal research tool built by attorneys for attorneys; connects Claude to US legal authority (statutes, rules of procedure, case law, court filings), plus a citation-verification system.
DingDuff
DingDuff gives Claude the ability to directly access the law without going through another AI system. Once connected to DingDuff, Claude can: • Browse, search, view, and download state and federal statutes, regulations, and court rules such as rules of civil procedure, rules of evidence, etc. • Search, view, and download federal and state court opinions using boolean operators, fielded searches, phrase matching, and citation-network lookup ("show every case citing X"). • Pull PACER dockets and documents through the CourtListener RECAP archive. • Run a deterministic citation review on a drafted memo or brief with the source passage highlighted alongside the cite for easy human verification. Quotes are checked against the cited authority programmatically (not by AI), preventing hallucinated citations from getting through. DingDuff was built by attorneys who use it daily, making it a tool that does what attorneys actually need and a tool that attorneys actually like to use.
Anthropic’s own published signals, snapshot of September 20, 2026; units undocumented — treat as ordinal.
Over time
Details
Tools(25)
- check_pacer_availability
- citecheck_review
- codes_browse
- codes_search
- codes_view
- courtlistener_full_search
- document_search_across_pacer_dockets
- metadata_view
- opinion_extract
- opinion_search
- fetch_opinion_file
- opinion_view
- pacer_docket_view
- pacer_document_view
- pacer_party_search
- retrieve_batch_screen
- search_courts
- search_for_pacer_docket
- search_within_pacer_docket
- see_related_pacer_entries
- show_citing_opinions
- show_related_opinions
- fetch_statute_file
- submit_batch_screen
- opinion_verify
Data from Claude’s public directory API, snapshotted daily by the MCP App Tracker. A listing describes what the directory publishes — not an endorsement.