CoCounsel
Also: Casetext
A legal AI tool from Thomson Reuters. It helps with tasks such as research and document review. Its output still needs checking.
The fuller definition
CoCounsel is Thomson Reuters' generative-AI legal assistant, offered alongside Westlaw and Practical Law for research, document review, and drafting tasks. Coverage and features depend on the subscription and jurisdiction.
- Question“What is the notice period?”
- RetrieveSearch the indexed documents; pull the best-matching passages.
- GenerateThe model answers from the question plus those passages.
- CiteEach statement points to the passage it came from.
Two things can still go wrong: the search misses the clause that matters, or the model misreads the clause it was given. The citation lets you check which happened.
A concrete example
A lawyer asks for a research memo and receives an answer with links into the publisher's database.
The distinction that matters
Research tools with retrieval still require you to open the authority and read it. The product's content scope matters as much as its model.
Related terms
Harvey
An AI platform made for law firms, used for research, document review, and drafting.
Documents & retrievalRAG — Retrieval-augmented generation
Letting the model look things up in your documents before answering, and show where the answer came from. Like an open-book exam.
Law & professional practiceFabricated citation
A case or quotation the AI invented. It looks real and is not.
Where it is taught
Choose an AI tool around the work productSource and further reading
Thomson Reuters · CoCounselThe definition and example are written for this library. The link gives background, official documentation or legal authority as labelled. Legal scope depends on the jurisdiction and current text; product features depend on release and settings.