How to use
- Copy the installation command and review the source package before installing it in your own agent environment.
- Check the source document for required tools, credentials and supported hosts.
- Describe your input and desired deliverable; review the output against the source material.
npx skills add https://github.com/langchain-ai/lca-skills --skill langsmith-fetchBefore you start
- Installation does not include a model subscription, API allowance or permission to access your files.
- Repository stars and installation counts describe activity, not an independent quality or security test.
Rendered from the source repository. Headings, examples, code, tables, links, and referenced images are preserved.
Fetching LangSmith Traces
Requires langsmith-fetch in project dependencies and LANGSMITH_API_KEY in a .env file.
Setup
First, find the .env file containing LANGSMITH_API_KEY:
find . -name ".env" -type f 2>/dev/null | head -5Commands
Use --env-file <path-to-.env> with all commands:
# Fetch recent traces (uses LANGSMITH_PROJECT from .env, or specify --project-uuid)
uv run --env-file <path> langsmith-fetch traces ./traces --limit 10
uv run --env-file <path> langsmith-fetch traces ./traces --project-uuid <uuid> --limit 10
# Fetch single trace by ID
uv run --env-file <path> langsmith-fetch trace <trace-id>
# Include metadata (timing, tokens, costs)
uv run --env-file <path> langsmith-fetch trace <trace-id> --include-metadataOutput Formats
--format pretty- Human-readable (default)--format json- Pretty-printed JSON--format raw- Compact JSON for piping
Troubleshooting Workflow
- Find
.env:find . -name ".env" -type f 2>/dev/null - Fetch recent traces:
uv run --env-file <path> langsmith-fetch traces ./debug --limit 10 - Find relevant trace in saved JSON files
- Check: What tools were called? What did they return? Was it correct/expected?



