From Task-Based Skills to Agentic Collaboration

Thomson Reuters has fundamentally re-engineered CoCounsel Legal, moving away from the original 2023 model of discrete, user-selected "skills" toward an agentic architecture. Built on Anthropic’s Claude Agent SDK, the new system functions as a digital colleague rather than a software tool. Users describe a matter in plain language, and the system generates a comprehensive plan, executes legal research using Westlaw and Practical Law, drafts work product with traceable citations, and adapts to new information as the matter evolves. This shift aims to provide a single, iterable work product rather than a series of piecemeal answers.

The 'Fiduciary-Grade' Standard

Central to this release is the company's "fiduciary-grade AI" framework, designed to meet the rigorous standards of professional practice. Thomson Reuters emphasizes three pillars for this standard:

  • Grounded Reasoning: The system anchors outputs in authoritative content from the initial reasoning step rather than performing post-hoc verification.
  • Traceability: Every citation is linked to its source, and the system’s reasoning process is inspectable by the user.
  • Data Integrity: The company maintains that confidential client data is not used to train third-party models.

This strategy positions CoCounsel as an "agentic operating system" intended to integrate into existing professional workflows. The company is actively pursuing interoperability through APIs and the Model Context Protocol (MCP), with planned integrations for platforms including Microsoft 365, iManage, NetDocuments, and HighQ.

Early Access and Future Capabilities

Beginning in August 2026, the new experience will be available to U.S. customers via a toggle, allowing them to switch between the legacy and agentic interfaces. Three core features are currently in development or rollout:

  • Workspaces: A persistent environment that maintains documents, precedents, and prior positions across sessions and team members.
  • Brief Builder: An agentic drafting tool specifically for motions and briefs that includes automated issue spotting and citation verification.
  • Organizational Intelligence: A layer that allows firms to encode their own institutional expertise into the system to ensure consistency across matters.

Beta testers reported high adoption rates across practice areas, noting that the tool's utility extended beyond traditional litigation into transactional and specialist work, such as employee benefits.