How to add a legal background to Claude Cowork
Trying to use an AI assistant to do legal work can be a daunting experience. You most likely will find yourself typing instructions over and over. “Read this contract and flag anything unusual, pay attention to detail, don’t skip anything, etc. Then when you start another task the instructions must be shared again because every session starts from scratch.
Enter Claude Cowork and its handy “plugins.” Despite the technical-sounding name, plugins are just saved instructions with a few custom tweaks.
Plugins = Saved Instructions
When you use Claude normally, you supply both the task (“review this lease”) and the method (“look for auto-renewal traps, unusual indemnification, anything a tenant should push back on”). The Claude Cowork plugin packages up the method part once, so you only have to bring the task.
That’s really all it is. A plugin is a tidy bundle of instructions, ready-made commands that you install into your Claude account and customize with your preferences. After that, instead of writing a paragraph of setup, you just upload a document and choose from a set of commands.
Anthropic, the company that makes Claude, has released a free set of these plugins to handle common tasks including marketing, finance, and of course, legal. Plugins don’s make the AI smarter they just provide the context it needs to do tasks. They run inside of Claude’s Cowork application, if you have Cowork installed you browse a built-in menu, click “install,” and the new commands simply appear. No coding, no setup files, no IT department required.
How to Use Cowork’s Legal Plugin—
The actual commands
After you install the legal plugin, you can trigger the commands just by mentioning them in the prompt in regular english or by typing a short command starting with a slash, then attaching or pasting the document. The legal plugin’s commands are:
- /legal:review-contract — clause-by-clause review with risk flags
- /legal:triage-nda — quick NDA assessment and routing
- /legal:vendor-check — review a vendor or third-party agreement
- /legal:compliance-check — check a document against policies and obligations
- /legal:risk-assessment — analyze and characterize the exposure
- /legal:brief — prepare a meeting or matter briefing
- /legal:respond — draft a reply from standard templates
Remember, you don’t have to memorize these. You can also just talk to Claude in plain English; “review this NDA for me” and it does the same thing. The commands are simply shortcuts for the tasks you’ll repeat most.
Don’t Skip the Interview
When you first install, the plugin walks you through a short setup interview — a guided Q&A where you tell it your preferred clauses, your risk tolerance, your jurisdiction — so its output matches your practice instead of generic boilerplate.
Getting Started
- Open Claude’s desktop app and find the Plugins sidebar in Cowork.
- Locate the Legal plugin and click Install.
- That’s it — the commands above are now available. (You can also install from claude.com/plugins in your web browser.)
How is this different from writing my own instructions?
If you read the related article in our last issue discussing AI context, you may remember the the do-it-yourself version of this, a plain text file named CLAUDE.md that you can prefill with instructions.
Think of it this way: a CLAUDE.md is a recipe card and a plugin is a fully stocked kitchen that someone set up for exactly the kind of cooking you do.
The plugin gives you the polished engine; your own CLAUDE.md adds your fingerprints your clauses, your county’s quirks, your voice. In fact, the plugin’s setup interview produces a profile that works much like a CLAUDE.md. Plenty of offices run both: install the plugin for the heavy lifting, then keep a short note of your own for the specifics only you know.
Don’t forget – Review every word
Used correctly, this plugin doesn’t replace your judgment. It hands you a faster, more organized starting point so you spend your time on the parts that actually require a lawyer. You remain responsible for everything that leaves your office.