The Claude legal plugin is a free, open-source add-on from Anthropic that teaches Claude Cowork how to do common in-house legal work: review contracts against your playbook, sort NDAs into green, yellow and red, check vendor agreements, prepare briefings and draft standard replies. It launched on January 30, 2026. A much bigger follow-up called Claude for Legal arrived on May 12, 2026, with 12 practice-area plugins and more than 20 legal connectors. You install either one from Customize → Plugins in Cowork on any paid Claude plan. This guide covers what each command does, how to install it, how to give it your own playbook, a worked NDA example, and what it can't do.
Checked against Anthropic's plugin announcements, GitHub repos and help center on October 14, 2026.
TL;DR
- There are two releases. The original Legal plugin (Jan 30, 2026) has five commands and six skills for in-house legal teams. Claude for Legal (May 12, 2026) adds 12 practice-area plugins and 20+ connectors to tools like Westlaw (via CoCounsel), iManage, Docusign and Harvey.
- The five commands are
/review-contract,/triage-nda,/vendor-check,/briefand/respond. - Install it in Cowork from Customize → Plugins → Discover. Plugins work on Pro, Max, Team and Enterprise, not Free.
- It reads your rules from a playbook file called
legal.local.md. The default playbook reflects U.S. positions, so customize it. - Anthropic says plainly that the plugin does not provide legal advice. Every output is a draft for a licensed attorney to check.
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Two releases: the Legal plugin vs Claude for Legal
Most confusion about "the Claude legal plugin" comes from people mixing up two separate launches. Here's how they differ.
| Legal plugin | Claude for Legal | |
|---|---|---|
| Released | January 30, 2026 | May 12, 2026 |
| What it is | One plugin, part of a set of 11 open-source Cowork plugins | 12 practice-area plugins plus 20+ legal connectors |
| Built for | In-house legal teams (commercial, product, privacy and compliance, litigation support) | Firms, in-house teams, law students and legal clinics |
| How it learns your rules | A playbook file, legal.local.md | A setup ("cold-start") interview for each plugin |
| Source code | anthropics/knowledge-work-plugins (opens in a new tab) | anthropics/claude-for-legal (opens in a new tab) (Apache-2.0) |
| Made by | Anthropic | Anthropic, with partner-built connectors |
Both are built by Anthropic. You'll sometimes see the legal plugin described as a third-party product; it isn't. Partners like Thomson Reuters and Harvey supply connectors, and Thomson Reuters also ships its own CoCounsel plugin, but the plugins themselves come from Anthropic.
The original Legal plugin (January 30, 2026)
Anthropic released 11 plugins for Cowork (opens in a new tab) as a research preview for all paid Claude users: Productivity, Enterprise search, Plugin Create/Customize, Sales, Finance, Data, Legal, Marketing, Customer support, Product management and Biology research. The Legal plugin is aimed at the everyday work of an in-house legal department: contracts, NDAs, vendor paperwork, privacy requests and getting ready for meetings.
It comes pre-configured to work with connectors for Slack, Box, Egnyte, Atlassian and Microsoft 365, and its documentation also covers Teams and contract-management, CRM and e-signature tools. If connectors are new to you, our Claude connectors guide explains how they work.
Claude for Legal (May 12, 2026)
Four months later, Anthropic announced Claude for Legal (opens in a new tab), a much larger package for Cowork. It has 12 plugins, one per practice area:
- Commercial Legal, Corporate Legal, Employment Legal, Privacy Legal
- Product Legal, Regulatory Legal, AI Governance Legal, IP Legal
- Litigation Legal, Law Student, Legal Clinic, Legal Builder Hub
Each plugin starts with a setup interview that captures your playbook, escalation chain, risk tolerance and house style, so you don't have to write a playbook file from scratch.
The connectors are the other half. Anthropic's announcement names tools across contracts (Definely, Docusign, Ironclad), deal rooms (Box, Datasite), document management (iManage, NetDocuments), e-discovery (Consilio, Everlaw, Relativity), research (Thomson Reuters CoCounsel Legal, Legal Data Hunter, Midpage, Trellis) and other legal AI tools (Harvey, Solve Intelligence), plus public-service tools like Courtroom5, Descrybe and Free Law Project. Per Anthropic, Thomson Reuters rebuilt CoCounsel on the Claude Agent SDK, and the connection runs both ways, with CoCounsel grounded in Westlaw, Practical Law and KeyCite.
The plugins are free, but many partner connectors need your own subscription to that partner's product. Legal aid clinics, public defenders and nonprofits can get discounted pricing through Claude for Nonprofits.
Anthropic also says legal professionals "have become the most engaged Claude Cowork users of any knowledge-work function." That's Anthropic's own claim; it hasn't published the numbers behind it.
Why the legal plugin made the news
The Legal plugin was one of 11 plugins released the same day, but it's the one that got headlines. On February 3, 2026, shares of the big legal-information companies dropped sharply. Morningstar reported (opens in a new tab) falls of roughly 16% for Thomson Reuters, 14% for RELX and 13% for Wolters Kluwer, and Reuters put Thomson Reuters' drop at nearly 18%.
That's why searches for "claude legal plugin" spiked in February even though the plugin came out at the end of January. Worth noting: Morningstar's own analysts argued the plugin doesn't do legal research, which is the core business of Thomson Reuters and RELX. And by May, Thomson Reuters was a Claude for Legal launch partner. Treat the sell-off as market commentary, not a verdict on what the plugin does.
Every command and skill, in plain English
The original Legal plugin has two kinds of building blocks. Commands are shortcuts you type to start a specific job. Skills are the know-how Claude draws on in the background, including when you just describe what you need in your own words. (Our explainer on what Claude Agent Skills are covers how skills work generally.)
Commands
| Command | What it does |
|---|---|
/review-contract | Reviews a contract against your playbook, flags where it deviates, suggests redlines and explains the business impact. You can give it a file, a URL or pasted text. |
/triage-nda | Sorts an incoming NDA into GREEN (standard, approve), YELLOW (needs counsel review) or RED (significant issues). |
/vendor-check [vendor] | Checks the status of existing agreements with a vendor (NDAs, MSAs, DPAs) across your connected systems. |
/brief | Prepares a briefing. Use /brief daily for a daily summary, /brief topic [query] for a specific subject, or /brief incident for an incident. |
/respond [inquiry-type] | Drafts a templated reply for common requests: a data subject request, a discovery hold, a vendor question, an NDA request, or a custom type. |
Skills
| Skill | What it covers |
|---|---|
contract-review | How to read a contract against your positions and mark what's off-standard |
nda-triage | The rules for sorting NDAs into green, yellow and red |
compliance | Privacy work: GDPR, CCPA, data processing agreement (DPA) review and data subject access requests |
canned-responses | Reusable templates for questions your team answers over and over |
legal-risk-assessment | Weighing and describing legal risk in business terms |
meeting-briefing | Pulling together what you need before a meeting |
In practice you'll use the commands when you know exactly what you want, and plain requests ("is this NDA OK to sign?") the rest of the time.
How to install the Claude legal plugin
You need the Claude desktop app with Cowork, on macOS or Windows, and a paid plan: Pro, Max, Team or Enterprise. Plugins aren't available on Free. Sharing or publishing plugins across an organization is Team and Enterprise only.
In Cowork:
- Open the Claude desktop app and go to the Cowork tab.
- Select Customize, then Plugins.
- Select Discover (some versions say Browse plugins).
- Find the plugin you want and select Add. The original Legal plugin is part of Anthropic's Knowledge Work set, which is the default marketplace. The Claude for Legal practice-area plugins live in Anthropic's separate Legal marketplace.
- If you have a zipped plugin file instead (for example, a customized copy from your team), you can upload it from the same screen.
Plugins you add are saved to your account and carry over to regular Claude chat and Claude Code. Full steps are in Anthropic's help article on using plugins in Cowork (opens in a new tab).
On Team and Enterprise, admins enable legal connectors and plugins in workspace settings and can restrict which plugins and marketplaces people are allowed to use. If you can't find it, ask your admin.
In Claude Code (if your team uses it), the original plugin installs with two commands:
claude plugin marketplace add anthropics/knowledge-work-plugins
claude plugin install legal@knowledge-work-pluginsFor a Claude for Legal plugin, the README's pattern is to add the claude-for-legal marketplace, install a plugin such as commercial-legal@claude-for-legal, restart, then run /commercial-legal:cold-start-interview to set it up.
One warning from Anthropic's own help center: plugins can include local tools that run with your computer's permissions, so "only install plugins from sources you trust." Anthropic's official marketplaces qualify; a random zip file from a forum doesn't.
Customize it with your firm's playbook
Out of the box, the plugin judges contracts against a generic playbook. That's useful for a demo and not much else. The real value comes when it knows your positions.
For the original Legal plugin, your rules live in a plain text file called legal.local.md. In Cowork, put it in any folder you've shared with Cowork. (In Claude Code it goes in the project's .claude/ folder.) The README's example defaults give you a sense of what goes in it:
- Liability cap of 12 months of fees
- NDA term of 2 to 3 years, or 5 years for trade secrets
- Standard carve-outs from confidentiality
Replace those with your own positions. A good playbook file covers, for each clause type you see often: your preferred position, what you'll accept as a fallback, what's a hard no, and who needs to sign off on exceptions. The more specific you are, the fewer judgment calls Claude has to guess at.
This matters even more outside the U.S. Anthropic's README says the default playbook reflects U.S. positions (Delaware, New York and California law), and non-U.S. users must customize it.
For Claude for Legal, you don't write the file by hand. Each plugin opens with its setup interview, asking about your playbook, escalation chain, risk calibration and house style.
If you want to go further and change how the plugin itself behaves, the January release included a Plugin Create/Customize plugin for exactly that, and both legal repos are open source.
Worked example: triaging an NDA
Here's what a typical NDA triage looks like once your playbook is in place. Say a prospective vendor sends over their mutual NDA and sales wants to sign it today.
You drop the PDF into your Cowork folder and type:
/triage-nda vendor-mutual-nda.pdf/triage-nda vendor-mutual-nda.pdf
Result: YELLOW (send to counsel for review)
Most terms match your playbook, but two need a lawyer's look:
- Term. Confidentiality lasts 7 years for all information. Your playbook says 2 to 3 years, with 5 years only for trade secrets.
- Residuals clause. Section 6 lets the vendor use information "retained in unaided memory." Your playbook doesn't allow residuals clauses without counsel approval.
Standard and within playbook: mutual obligations, the usual exclusions (public, already known, independently developed), compelled-disclosure notice, return or destroy at the end.
Suggested redlines for both issues are attached for counsel.
A GREEN result means the NDA matches your standard and can go through your normal approval. RED means significant problems, like one-sided terms you'd never accept. Either way, the decision stays with a person: the plugin sorts the pile so your lawyers spend their time on the yellow and red ones.
The same pattern works for the other commands. /review-contract on an MSA gives you deviations and redlines. /vendor-check before a renewal tells you which agreements already exist with that vendor. If you need a first draft of a contract rather than a review, our free AI contract generator builds a structured prompt and clause checklist for you.
Limits: what the legal plugin can't do
It is not legal advice
Anthropic's README states that the plugin "does not provide legal advice" and that a licensed attorney should review its output. Claude for Legal's README goes further: every output is a draft for attorney review, the plugins don't represent Anthropic's legal positions, and nothing is filed or sent without an attorney sign-off step.
Anthropic's usage policy also treats legal as a high-risk use. Under the version taking effect November 12, 2026, anyone deploying Claude to advise a person on their legal rights, obligations or liability, or to prepare documents for someone to sign or file, needs a qualified human reviewer (licensed where the law requires) and must disclose that AI was used. General legal information falls outside those requirements.
Verify everything, especially citations
Claude can misread a clause or invent a case. Trackers now count well over a thousand court cases worldwide involving AI-fabricated citations or quotes, and lawyers have been fined and referred to their state bars over them. Claude for Legal flags citations that come only from the model's own knowledge with [verify], and its README recommends connecting a research tool such as CourtListener first, because otherwise citations are unverified. Read every case and clause yourself before relying on it.
Privilege: the Heppner ruling
In United States v. Heppner (S.D.N.Y., February 2026), Judge Jed Rakoff held that about 31 documents a defendant created on his own using consumer Claude were not protected by attorney-client privilege or work product. Claude isn't a lawyer, a consumer platform owes no duty of confidentiality, and sending the chats to counsel afterward didn't make them privileged. It's one district court's decision and not binding elsewhere, and the court left room for AI use directed by counsel. The practical lesson: if you're a client, talk to your lawyer before you start working through your legal problem in an AI chat.
Data handling
- Team and Enterprise data isn't used for training under Anthropic's commercial terms.
- Pro and Max are consumer plans. Since the August 2025 terms update, you choose whether your chats are used for training. If you allow it, data is kept for 5 years; if not, 30 days. Check your privacy setting before you put client material in.
- Zero data retention exists but doesn't currently cover Cowork or claude.ai chat, including on Team and Enterprise. Don't assume it applies.
ABA Formal Opinion 512 (July 2024) expects lawyers to understand a tool's limits, verify its output and get client informed consent before putting client information into self-learning tools. The plugin doesn't change any of that. For the bigger picture, see our hub guide to Claude for lawyers and our fair roundup of the best AI for lawyers.
Frequently asked questions
What is the Claude legal plugin?
It's a free, open-source plugin from Anthropic that adds legal workflows to Claude Cowork. Released on January 30, 2026, it includes five commands (/review-contract, /triage-nda, /vendor-check, /brief and /respond) and six skills for contract review, NDA triage, compliance, canned responses, risk assessment and meeting briefings.
What is the difference between the legal plugin and Claude for Legal?
The legal plugin is the single plugin Anthropic released on January 30, 2026 for in-house legal teams. Claude for Legal, announced May 12, 2026, is a larger package of 12 practice-area plugins, such as Commercial, Employment, Privacy, IP and Litigation, plus more than 20 connectors to legal tools like CoCounsel, iManage, Docusign and Harvey.
How do I install the Claude legal plugin?
Open the Claude desktop app, go to the Cowork tab, select Customize, then Plugins, then Discover. Find the plugin and select Add. You need a paid plan (Pro, Max, Team or Enterprise). On Team and Enterprise, an admin may need to allow the plugin first.
Is the Claude legal plugin free?
The plugin itself is free and open source, but it needs a paid Claude plan, since plugins aren't available on Free. Some Claude for Legal connectors, such as CoCounsel, also require a subscription to the partner's own product.
Can I use the Claude legal plugin outside the U.S.?
Yes, but you should customize it. Anthropic says the default playbook reflects U.S. positions under Delaware, New York and California law, and non-U.S. users must update the playbook file with their own positions before relying on the results.
Does the Claude legal plugin give legal advice?
No. Anthropic states that the plugin does not provide legal advice and that a licensed attorney should review its output. Treat everything it produces as a draft, and verify every clause and citation yourself.
Learn Cowork before you add plugins
Plugins make the most sense once you're comfortable with Cowork itself: sharing folders, connecting your tools and checking Claude's work. The free Claude Cowork course walks you through all of it with no coding required, and then the legal plugin becomes one more tool you know how to use well.