langsmith-observability

Trace, evaluate, and monitor LLM applications using the LangSmith Python SDK.

1|Updated Mar 5, 2026
One-click install
npx skills add https://github.com/Clay-HHK/claude-skills --skill langsmith-observability-clay-hhk
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: langsmith-observability
Source: https://github.com/Clay-HHK/claude-skills/tree/main/langsmith
Command: npx skills add https://github.com/Clay-HHK/claude-skills --skill langsmith-observability-clay-hhk

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires langsmith, and includes references (resource) components.

What problem does it solve? Debugging and evaluating LLM applications is difficult without visibility into prompts, chains, and agent executions. This Skill provides tracing, dataset-based evaluation, and production monitoring workflows for LLM systems using LangSmith. ## Core Features & Use Cases - Automatic Tracing: Capture inputs, outputs, latency, and token usage for LLM calls using the @traceable decorator or the OpenAI wrapper. - Dataset Evaluation: Build test datasets from production traces and run custom or built-in evaluators to measure output quality. - Production Monitoring: Track errors, costs, feedback scores, and latency trends across projects, with sampling and batching controls. - Use Case: A team shipping a RAG chatbot traces every retrieval and generation step, builds a regression dataset from flagged production runs, and runs automated evaluations in CI to catch accuracy drops before deployment. ## Quick Start Set the LANGSMITH_API_KEY and LANGSMITH_TRACING environment variables, then ask the assistant to add @traceable decorators to your LLM functions so their calls appear in the LangSmith dashboard.

Frequently Asked Questions about langsmith-observability

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I trace LLM calls with LangSmith in Python?▼

Set LANGSMITH_TRACING=true and LANGSMITH_API_KEY, then decorate functions with @traceable or wrap the OpenAI client using langsmith.wrappers.wrap_openai. All calls are automatically sent to your LangSmith project with inputs, outputs, and latency.

How do I evaluate LLM outputs against a dataset in LangSmith?▼

Create a dataset with client.create_dataset and add examples, then call langsmith.evaluate with your model function, the dataset name, and evaluator functions. Evaluators receive each run and example and return score dictionaries.

LangSmith vs Weights & Biases for LLM monitoring?▼

LangSmith focuses on LLM tracing, prompt debugging, and output evaluation against datasets. Weights & Biases targets deep learning experiment tracking and model training, while MLflow covers general ML lifecycle and model registry needs.

Why are my LangSmith traces not appearing in the dashboard?▼

Verify LANGSMITH_TRACING is set to true, the API key is valid, and the project name is correct. Call client.flush() to send pending batched traces, and test connectivity by listing projects with the Client.

How do I reduce tracing overhead in production with LangSmith?▼

Enable background batching with Client(auto_batch_tracing=True), set LANGSMITH_TRACING_SAMPLING_RATE to sample a fraction of traces, and use process_inputs to strip large or sensitive fields from recorded payloads.