Skills, available through our Plugin
The easiest way to get all five skills is the DingDuff plugin, which installs them at once and keeps them current. Prefer to add them by hand? Download any of them below — just remember, without the plugin, you’ll have to keep up with updates yourself.
The skills are released under the DingDuff Skills License 1.0. Use them in your paid work without restriction, change them to suit your practice, and keep everything you produce with them. The conditions apply only if you pass a skill on to someone else.
Legal Research Strongly recommended v2.7
End-to-end legal research — finds, retrieves, reads, and validates the controlling cases, statutes, and regulations, maps the citation network and statutory landscape, and confirms everything is still good law. Scales from a quick “what’s the law on X” to a full doctrinal map.
Two-tier validation. Every case gets a quick screen; the cases your argument actually rests on get handed to the full Validity Check skill. Claude weighs how load-bearing each case is against the cost of the deep check, and then tells you which cases got which. A quick screen is a smoke test, not a verification, and the answer says so instead of letting the two look alike.
DingDuff works without it, but it works a lot better with it: this skill carries the research method and the bulk of our anti-hallucination instructions, which we can’t push through the connector itself. If you install only one, install this one.
DownloadLegal Analysis Optional v1.2
Reasoning engine — frames the issues, synthesizes the governing rule, analyzes the facts against it, organizes the proof (CRAC/CREAC), and deploys authority. Use before drafting any memo, brief, motion, or letter.
DownloadValidity Check Optional v3.6
Before an argument rests on a case, confirms the case is still good law for the proposition you’re citing it for — tracing its appellate history, sweeping forward for opinions that overruled or narrowed it, and checking the authorities the case itself leaned on. Returns a verdict with its confidence and an honest statement of what it could not see.
It reads the docket. For a federal case, the most common way a decision stops being law is that it was appealed, reversed, vacated, or amended on reconsideration — and a vacatur on reconsideration often leaves no published opinion for a citation search to find. The skill pulls the PACER docket and reads the orders entered after the opinion issued, so that history shows up in the clerk’s own entries. It will tell you the two limits: PACER is federal-only, so state cases don’t get this pass, and docket coverage comes from the crowd-sourced RECAP archive, so a missing entry is not proof nothing happened.
DownloadCitation Check Optional v2.5.8
After you draft a memo (Markdown, Word, or Google Docs), verifies every citation against your stored opinions and statutes plus any other sources you supply, checks that each highlighted passage is the on-point part of the source, then opens an interactive attorney review panel and records your verdicts.
DownloadLegal Citation Format Optional v1.4
Formats citations the way courts expect — signals, pincites, short forms (id./supra), string cites, and same-matter filings.
DownloadOnce a skill is in your skill library, you mostly don’t have to think about it. Claude is built to automatically grab and implement the skills from your skill catalog that Claude identifies as best suited to the task you’re asking it to accomplish.
Because of this, Claude will nearly always reach for the Legal Research skill on its own while using DingDuff. But if you want to be sure it does (this skill carries the most anti-hallucination instructions) select it manually with the “+” (the skill picker) in your chat window.
The Legal Analysis skill is optional and builds in a structured CREAC/IRAC method. If you ask Claude specifically to draft a memo, it will likely grab this skill. But if you want to ensure it does, also add it with the “+” sign in the chat window. (Again, this skill is optional: while Kyle likes to use this skill, Stephanie almost never uses it.)
Validity Check is the one to reach for when an argument is about to rest on a particular case. If you have Legal Research installed it calls this skill on its own, on the cases it judges load-bearing, and reports which cases got the deep check and which only got a screen. You can always ask for it by name — “check whether Smith is still good law for that proposition” — or ask for a specific case to be checked the hard way. It runs in a subagent, so your main chat stays fast while it works.
Citation Check and Legal Citation Format only run when you specifically ask for them. If you select Citation Check with the “+” before Claude drafts a memo or brief it will produce both the draft and a companion cite-check file; or you can run it on its own to cite-check a memo or brief already saved in your desktop folder. The same goes for the Legal Citation Format skill.