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LangSmith is LangChain’s platform for tracing and evaluating LLM applications. Connect your workspace to ClosedLoop AI to put what your LLM application actually does alongside every other source of customer truth.

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What ClosedLoop AI Reads

Connecting stores your key. It does not start reading your workspace.
Connecting makes one request to LangSmith, to confirm the key works for the region you chose. ClosedLoop AI reads whether that request succeeded, nothing from its response, and then stores your key and region. No projects, runs, traces, datasets or prompts are read. Reading run data is not enabled yet. When it is, the scope is agreed with you first, and it is narrow by design: The reason for nominating projects is that a LangSmith service key is workspace-wide, so the limit has to be one ClosedLoop AI applies rather than one the key enforces.

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Connection Method

LangSmith uses API key authentication. Both key types work: You also choose a region. A LangSmith key works only in the region it was created in, so a key issued in the EU is rejected against the US region and the other way round. ClosedLoop AI verifies your key against LangSmith before storing it, so a wrong key or a wrong region tells you immediately instead of failing quietly later.

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Setup Guide

  1. In LangSmith, open Settings, then API Keys
  2. Click Create API Key
  3. Choose Service Key as the key type
  4. Set Expiration Date to Never
  5. Click Create, then copy the key and save it somewhere safe: LangSmith only shows it once
The expiration field defaults to a dated option. If you pick anything other than Never, the connection stops working on that date and you will need to reconnect with a new key.
Look at the URL you use for LangSmith:
  • smith.langchain.com means your workspace is in the US region
  • eu.smith.langchain.com means your workspace is in the EU region
Pick the matching region when you connect. Choosing the wrong one is the most common reason a valid key is refused.
  1. In ClosedLoop AI, go to Integrations
  2. Find LangSmith and click Connect
  3. Paste your LangSmith API key
  4. Select your region, US or EU
  5. Click Connect
Your key is checked against LangSmith and stored securely, scoped to your workspace and region.

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Troubleshooting

Connect LangSmith

Set up your LangSmith integration in the ClosedLoop AI dashboard