LangChain has announced that LangSmith now supports operation as a remote MCP server, effective May 9, 2026. Users can access LangSmith features such as traces, projects, datasets, prompts, and billing information directly through any MCP-compatible client without needing a local server or API key. The server utilizes the Model Context Protocol (MCP) with OAuth 2.1 authentication and dynamic client registration, and offers three regional endpoints: United States (GCP), European Union (GCP), and United States (AWS). This new functionality allows Claude Code and Cursor users to connect easily via profile configuration. Available tools include thread management, prompt management, trace execution, dataset operations, experiment evaluation, and billing inquiries. However, self-hosted LangSmith users are not supported and must operate a standalone MCP server.