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Documentation Index

Fetch the complete documentation index at: https://docs.idun-group.com/llms.txt

Use this file to discover all available pages before exploring further.

Set up LangSmith to debug, trace, and monitor your agents from the LangSmith dashboard.
Before starting, complete the quickstart guide to have an agent running on Idun Engine.

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Set up LangSmith observability

1

Get your LangSmith API key

If you do not have a LangSmith API key yet:
  1. Go to LangSmith
  2. Sign up or log in to your account
  3. Navigate to Settings (gear icon) > API Keys
  4. Click Create API Key
  5. Copy your API Key
2

Configure LangSmith in the standalone

Open the running standalone at /admin/observability/ and click LangSmith. Fill in:
  • API Key: Your LangSmith API key (starts with lsv2-...)
  • Project Name: The name of the project in LangSmith (for example, default or prod-agent)
  • Endpoint: (Optional) Custom endpoint if you are self-hosting LangSmith (defaults to https://api.smith.langchain.com)
  • Run Name: (Optional) Display name for each trace run in LangSmith (for example, my-agent)
Observability admin page with LangSmith selected
Save the form. The reload pipeline re-instantiates the engine with the new observability config; the next agent run starts streaming spans to LangSmith.
Keep your API key secure. Do not commit it to version control or share it publicly.
Alternatively, configure LangSmith in your config.yaml for first-boot seeding or engine-only mode:
config.yaml
observability:
  - provider: "LANGSMITH"
    enabled: true
    config:
      api_key: "${LANGSMITH_API_KEY}"
      project_name: "prod-agent"
      run_name: "my-agent"

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View observability data

Once your agent is running with observability enabled:
  1. Interact with your agent through the chat UI at / or the API at /agent/run
  2. Open your LangSmith dashboard at smith.langchain.com
  3. Navigate to your project to view traces
You will see traces showing the execution run tree, LLM inputs/outputs, and latency. Each trace run is named after your agent by default.

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Best practices

  • Use distinct projects for development and production environments
  • Tag runs to filter traces when investigating specific issues (configured within agent logic)
  • Review error traces in LangSmith to identify and resolve problems quickly

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Troubleshooting

  1. Check API key: Verify it is valid and has the required permissions
  2. Verify project name: Traces are sent to the “default” project if the project name is not specified or is incorrect
  3. Check tracing toggle: Confirm the tracing toggle is enabled in the configuration

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Next steps

Local trace store

Inspect every agent run in the bundled admin UI alongside LangSmith.

Observability overview

Compare built-in providers and their configuration shapes.

Custom handler

Write a handler for any provider not on the shipping list.
Last modified on May 20, 2026