Luisa Crawford
Dec 10, 2025 18:52
LangChain introduces LangSmith Fetch, a CLI device that integrates LangSmith tracing into developer workflows instantly from the terminal, optimizing agent debugging processes.
LangChain has introduced the discharge of LangSmith Fetch, an progressive command-line interface (CLI) device designed to streamline the debugging course of for builders working with brokers. This device integrates the excellent capabilities of LangSmith tracing instantly into the terminal and built-in growth environments (IDEs), enhancing the effectivity of agent debugging workflows.
Addressing Developer Frustrations
LangSmith Fetch goals to eradicate the widespread friction builders encounter when debugging brokers. Historically, builders utilizing coding instruments akin to Claude Code or Cursor wanted to change to the LangSmith UI to entry hint knowledge, disrupting their workflow. With LangSmith Fetch, builders can now entry hint knowledge instantly from the terminal, lowering the necessity for context-switching and enhancing productiveness.
Options and Functionalities
The device is constructed round two main developer workflows: quick hint fetching and bulk knowledge export. Builders can retrieve the newest hint knowledge with a easy command, bypassing the necessity for internet interfaces and handbook knowledge dealing with. For example, the command langsmith-fetch traces –project-uuid <your-uuid> –format json gives instantaneous entry to hint knowledge in JSON format.
LangSmith Fetch additionally helps bulk export functionalities, permitting builders to extract giant datasets for analysis and evaluation. This function is especially helpful for creating check suites and analyzing manufacturing failures.
Empowering Coding Brokers
One of many standout options of LangSmith Fetch is its skill to boost the capabilities of coding brokers. By offering direct entry to complete agent execution knowledge, coding brokers like Claude Code can analyze decision-making processes, establish inefficiencies, and recommend enhancements based mostly on actual execution knowledge. This integration transforms coding brokers into highly effective debugging instruments.
Integration and Compatibility
LangSmith Fetch seamlessly integrates with present LangSmith setups with out requiring extra configuration. Builders can set up the device by way of pip and start using its options instantly. The device makes use of the identical authentication protocols because the LangSmith platform, making certain a easy transition for present customers.
Why a CLI Instrument?
The choice to develop a CLI device, slightly than an MCP server, was pushed by the necessity for flexibility and compatibility with present developer workflows. Whereas MCP (Mannequin Context Protocol) excels in real-time device calling, a CLI device affords better versatility, permitting builders to combine it into varied workflows and instruments with out restrictions.
LangChain emphasizes the CLI’s alignment with the Unix philosophy of flexibility and composability, enabling builders to leverage LangSmith Fetch in quite a few methods, from fast hint inspections to batch processing and integration with coding brokers.
For extra info and to get began with LangSmith Fetch, go to the LangChain Weblog.
Picture supply: Shutterstock








