---
title: LangSmith
slug: /integrations-langsmith
---

LangSmith is a full-lifecycle DevOps service from LangChain that provides monitoring and observability. To integrate with Langflow, add your LangChain API key and configuration as Langflow environment variables, and then start Langflow.

1. Obtain your LangChain API key from [https://smith.langchain.com](https://smith.langchain.com/)
2. Set the following environment variables in your Langflow `.env` file, replacing `LANGCHAIN_API_KEY` and `LANGSMITH_PROJECT_NAME` with your own values:

    ```text
    LANGSMITH_TRACING=True
    LANGSMITH_ENDPOINT=https://api.smith.langchain.com/
    LANGSMITH_API_KEY=LANGCHAIN_API_KEY
    LANGSMITH_PROJECT=LANGSMITH_PROJECT_NAME
    ```

    Alternatively, you can export the environment variables in your terminal instead of adding them to the `.env` file:

    ```bash
    export LANGSMITH_TRACING=True && export LANGSMITH_ENDPOINT="https://api.smith.langchain.com/" && export LANGSMITH_API_KEY="LANGCHAIN_API_KEY" && export LANGSMITH_PROJECT="LANGSMITH_PROJECT_NAME"
    ```

3. Restart Langflow with your modified `.env` file or from the terminal where you set your environment variables:

    ```bash
    langflow run --env-file .env
    ```

    If you set the environment variables in your terminal, you can omit `--env-file`.
    However, Langflow can source environment variables from `.env` _and_ your terminal.
    For more information, see [Langflow environment variables](/environment-variables).

4. Run a flow in Langflow to generate some activity.

5. View the LangSmith dashboard for monitoring and observability.

    ![LangSmith dashboard](/img/langsmith-dashboard.png)