Create an account and API key

To get started with LangSmith, you need to create an account. You can sign up for a free account in the LangSmith UI. LangSmith supports sign in with Google, GitHub, and email.

API keys

LangSmith supports two types of API keys. You can use both types of token to authenticate requests to the LangSmith API, but they have different use cases:

• Personal Access Tokens (PATs) inherit the permissions of the user who created them. Use PATs for personal scripts or tools.
• Service keys can be scoped to specific workspaces or the entire organization. Use service keys for applications and production services.

Create an API key

To log traces and run evaluations with LangSmith, you will need to create an API key to authenticate your requests.

1. Open API Keys settings

   Navigate to the Settings page and select the API Keys section.

2. Configure the key type

   For service keys, choose between an organization-scoped and workspace-scoped key. If the key is workspace-scoped, you must specify the workspaces.

   Enterprise users can also assign specific workspace roles to service keys, which adjusts their permissions independently of any user.

3. Set expiration

   Set the key’s expiration. The key becomes unusable after the number of days chosen, or never, if that is selected.

4. Create the key

   Click Create API Key.

   LangSmith will display the API key only once, so make sure to copy it and store it in a safe place.

Delete an API key

1. Open API Keys settings

   Navigate to the Settings page and scroll to the API Keys section.

2. Find the key

   Find the API key you need to delete from the table. Toggle Personal or Service as needed.

3. Delete the key

   Select the trash icon in the Actions column and confirm deletion.

Configure the SDK

After setting LANGSMITH_API_KEY, you may need the following additional environment variables.

LANGSMITH_ENDPOINT controls which LangSmith server the SDK sends data to. It defaults to https://api.smith.langchain.com (US cloud). Set it only if you are on a different deployment:

• EU instance: LANGSMITH_ENDPOINT=https://eu.api.smith.langchain.com
• AWS-hosted US instance: LANGSMITH_ENDPOINT=https://aws.api.smith.langchain.com

LANGSMITH_WORKSPACE_ID is required only if your API key is scoped to more than one workspace:

LANGSMITH_WORKSPACE_ID=<Workspace ID>

Using API keys outside of the SDK

See instructions for managing your organization via API.

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