Thomson Reuters has released the next generation of CoCounsel Legal, a fully agentic AI system for legal professionals that moves from research and issue analysis through to draft work product in one workflow. The new version, now generally available in the United States, combines legal research, drafting, legal intelligence, verification, and matter-centric workflows in a single connected environment built on Westlaw and Practical Law content.
The release arrives as law firms and legal departments shift from AI experimentation to enterprise-wide adoption, evaluating tools on whether they can be trusted to support actual legal work rather than just generate answers. CoCounsel Legal addresses this with transparent reasoning, citation-backed results, and agentic capabilities that can orchestrate complex, multi-step tasks.
"The legal industry is moving beyond AI that simply generates answers," said Ragah Ramanathan, President, Legal Professionals, Thomson Reuters. "Whether you're at an Am Law 100 firm, a midsize or small practice, or a corporate legal department, the challenge is the same: turning insight into action. The next generation of CoCounsel Legal helps professionals complete legal work with confidence by combining trusted legal content, agentic intelligence, and workflow execution in a single experience. That's a fundamentally different approach to legal AI."
Built on Anthropic's Claude Agent SDK, CoCounsel Legal plans, reasons, and executes across legal workflows rather than responding to isolated prompts. Every output remains grounded in verified legal authority and follows Thomson Reuters Fiduciary-Grade AI principles, which cover transparency, accountability, and confidence.
"What sets the new CoCounsel Legal apart is that it doesn't just answer questions; it builds toward real work product," said Jennifer Eng, Shareholder, Commercial Litigation at Polsinelli. "Its grounding in Westlaw gives me confidence that the research is authoritative, while the agentic workflow carries that analysis through reasoning, drafting, and verification. As a litigator, I need speed without sacrificing precision, and this is the first tool that gets me from a complex legal question to a defensible draft, faster and with real confidence."
New capabilities for legal work
The newest addition is Westlaw Brief Builder, which helps litigators move from research and issue analysis to first-draft brief creation while validating authority along the way. Powered by Westlaw, KeyCite, and Practical Law, it proposes relevant facts, arguments, and supporting authority while keeping lawyers in control of strategy, legal theory, and final decisions. The tool is designed to support thinking, not replace it, at every stage from spotting issues to backing them with authoritative law.
Workspaces provide a dedicated environment for each matter, combining firm and legal department documents, precedents, and institutional knowledge. Context is preserved across matters and teams, helping legal professionals build on prior work instead of starting from scratch.
The Drafting Agent in CoCounsel for Word lets legal professionals draft, edit, and review agreements using natural language instructions directly within Microsoft Word, using Practical Law content alongside an organization's own documents and playbooks.
Tabular Analysis, designed for high-volume document review, allows attorneys to review up to 10,000 documents and ask up to 100 questions, with results returned in a dynamic, filterable table. It runs on Thomson Reuters' proprietary legal-focused large language model, which the company says is optimized for complex legal analysis where domain-specific AI can outperform general-purpose models.
Deep Research Verify checks whether cited Westlaw and Practical Law authority supports specific legal assertions, helping legal professionals strengthen confidence in AI-assisted work product.
For legal professionals still building their skills with these tools, an AI Learning Path for Paralegals covers practical applications for document review and legal research workflows. Broader coverage of AI for Legal includes case studies and guidance on how law firms are adopting these systems.
Partnerships and availability
Thomson Reuters continues its work with Anthropic, including an expanded CoCounsel Legal MCP with Claude launched in August. The integration lets legal professionals access CoCounsel Legal directly from Claude and receive cited work product grounded in Westlaw, Practical Law, and their organization's own knowledge.
The company is also expanding its collaboration with AWS, with a forthcoming MCP connection designed to extend CoCounsel Legal into Amazon Quick, AWS's AI assistant for work, as well as other AWS offerings. Beginning in October, an integration with Reveal will allow litigation teams to bring reviewed evidence directly from Reveal into CoCounsel Legal for research, analysis, and drafting, eliminating the need to manually export and re-upload documents.
The new CoCounsel Legal experience is available now in the United States. Availability in Canada, the United Kingdom, and Australia is expected later this year.
Why this matters for legal professionals
For litigators and legal teams, the practical shift is that AI tools now carry work from research through to a defensible first draft within a single workflow, rather than requiring manual transfer between separate systems. The combination of citation-backed research, agentic drafting, and verification tools means the bottleneck is no longer producing work product, but reviewing and refining it. Law firms and legal departments evaluating AI should focus on whether tools can cite their authority, preserve matter context, and keep the lawyer in control of strategy.
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