Luisa Crawford
Dec 10, 2025 18:52
LangChain introduces LangSmith Fetch, a CLI instrument that integrates LangSmith tracing into developer workflows straight from the terminal, optimizing agent debugging processes.
LangChain has introduced the discharge of LangSmith Fetch, an progressive command-line interface (CLI) instrument designed to streamline the debugging course of for builders working with brokers. This instrument integrates the excellent capabilities of LangSmith tracing straight into the terminal and built-in improvement environments (IDEs), enhancing the effectivity of agent debugging workflows.
Addressing Developer Frustrations
LangSmith Fetch goals to get rid of the widespread friction builders encounter when debugging brokers. Historically, builders utilizing coding instruments comparable to Claude Code or Cursor wanted to modify to the LangSmith UI to entry hint information, disrupting their workflow. With LangSmith Fetch, builders can now entry hint information straight from the terminal, lowering the necessity for context-switching and enhancing productiveness.
Options and Functionalities
The instrument is constructed round two main developer workflows: speedy hint fetching and bulk information export. Builders can retrieve the newest hint information with a easy command, bypassing the necessity for net interfaces and guide information dealing with. As an example, the command langsmith-fetch traces --project-uuid offers prompt entry to hint information in JSON format.
LangSmith Fetch additionally helps bulk export functionalities, permitting builders to extract giant datasets for analysis and evaluation. This characteristic is especially useful for creating check suites and analyzing manufacturing failures.
Empowering Coding Brokers
One of many standout options of LangSmith Fetch is its potential to reinforce the capabilities of coding brokers. By offering direct entry to complete agent execution information, coding brokers like Claude Code can analyze decision-making processes, determine inefficiencies, and recommend enhancements primarily based on actual execution information. 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 instrument by way of pip and start using its options instantly. The instrument 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 instrument, 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 instrument calling, a CLI instrument provides larger versatility, permitting builders to combine it into numerous 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 data and to get began with LangSmith Fetch, go to the LangChain Weblog.
Picture supply: Shutterstock

