> ## Documentation Index
> Fetch the complete documentation index at: https://docs.langchain.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Trace Claude Cowork sessions

> Send Claude Cowork tasks, tool calls, and skill use to LangSmith with the LangSmith tracing plugin for Claude.

[Claude Cowork](https://claude.com/docs/cowork/guide/plugins) runs the same plugins as Claude Code, so the [LangSmith tracing plugin for Claude Code](https://docs.langchain.com/langsmith/trace-claude-code.md) also traces Cowork tasks. Each turn becomes a trace, and a task's turns are grouped into a thread.

## Prerequisites

* Access to Claude Cowork in the Claude desktop app.
* A LangSmith account.

## Install the plugin

Cowork installs plugins from your claude.ai account. To install the plugin for yourself:

1. Go to **Customize** > **Plugins** on claude.ai.
2. Add `langchain-ai/langsmith-claude-code-plugins` or `https://github.com/langchain-ai/langsmith-claude-code-plugins` as a marketplace.
3. Install the `langsmith-tracing` plugin from that marketplace.

The plugin loads into the next Cowork task you start. To install it for everyone see [Deploy to your organization](#deploy-to-your-organization). For more on installing plugins, see [Cowork plugins](https://claude.com/docs/cowork/guide/plugins) in the Claude docs.

## Sign in

Sign in once with the LangSmith CLI. See [Install the LangSmith CLI](https://docs.langchain.com/langsmith/langsmith-cli.md#install) if you do not have it yet.

```bash theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
langsmith auth login
```

If you use the CLI sign-in and have more than one profile, set `profile` in your config file to the one the plugin should use. Your own `api_key` ignores this setting, but a generic `LANGSMITH_API_KEY` is not used as a fallback while `profile` is set.

To use an API key instead, add it to `~/.claude/langsmith.json`, the same file Claude Code reads:

```json theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
{ "enabled": true, "api_key": "lsv2_pt_...", "agent_id": "shared-claude" }
```

If more than one credential is set, the plugin uses the first one it finds:

1. The plugin's own key from `api_key` or `CC_LANGSMITH_API_KEY`.
2. Your `langsmith auth login` sign-in.
3. A generic `LANGSMITH_API_KEY` from your environment.

Tracing stops when your sign-in expires or your key is rejected, and turns from that gap are never uploaded. Admins can also [require a working sign-in](#require-a-working-sign-in) for every prompt.

## Turn on tracing

Tracing is off until you turn it on in `~/.claude/langsmith.json`, unless your admin already turned it on with a [managed file](#lock-settings). Send traces to an [agent](https://docs.langchain.com/langsmith/log-traces-to-agent.md#send-traces-to-an-agent) with `agent_id`:

```json theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
{ "enabled": true, "agent_id": "shared-claude" }
```

Or send them to a project with `project`:

```json theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
{ "enabled": true, "project": "shared-claude" }
```

Use either one. If you set both, `agent_id` wins.

Start a Cowork task and open your agent or project in [LangSmith](https://smith.langchain.com?utm_source=docs\&utm_medium=cta\&utm_campaign=langsmith-signup\&utm_content=langsmith-trace-claude-cowork). Skill calls record which skill ran, so you can filter traces by skill.

## Deploy to your organization

Admins can install the plugin for everyone and control how it traces from one place.

### Install for everyone

Organization owners can add the plugin to every member's claude.ai account, so it reaches Cowork and Claude Code together. For the setup, see [Choose a rollout route](https://claude.com/docs/plugins/org-rollout).

### Lock settings

An admin can lock tracing settings for every user with a managed file at `~/.langsmith-plugins/managed.json` in each user's home folder. The Claude Code, Cursor, and Codex plugins all read this file, and its settings override the user's own config files and environment variables.

```json theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
{
  "api_url": "https://langsmith.example.com",
  "project": "engineering",
  "strict_auth": true
}
```

The managed file works on macOS and Linux. The plugin only trusts it when:

* Root owns the file and its folder.
* No other user can write to either.
* Neither is a symlink.

If the file exists but fails these checks, tracing stops and the user sees a message to contact their admin. Locking a setting also locks the settings tied to it, so users cannot route traces around the lock. For example, locking `project` also stops users from adding their own [replicas](https://docs.langchain.com/langsmith/trace-replicas.md) or sending traces to an agent with `agent_id`.

Admins usually install the file on each machine with a mobile device management (MDM) tool such as Jamf or Microsoft Intune. For every setting you can lock, see the [plugin settings guide](https://github.com/langchain-ai/langsmith-plugin-binary/blob/main/docs/settings.md).

> **Example setup script**
>
> Run this as root for each user, with `USER_HOME` set to that user's home folder:
>
> ```bash theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
> USER_HOME=/Users/developer
> mkdir -p "$USER_HOME/.langsmith-plugins"
> cp managed.json "$USER_HOME/.langsmith-plugins/managed.json"
> chown root:wheel "$USER_HOME/.langsmith-plugins" "$USER_HOME/.langsmith-plugins/managed.json"
> chmod 755 "$USER_HOME/.langsmith-plugins"
> chmod 644 "$USER_HOME/.langsmith-plugins/managed.json"
> ```
>
> On Linux, use `root:root` instead of `root:wheel`. For the full script, see [Set it up on macOS](https://github.com/langchain-ai/langsmith-plugin-binary/blob/main/docs/settings.md#set-it-up-on-macos).

### Require a working sign-in

Strict auth blocks every prompt until the user's sign-in or key works, so no session goes untraced. It is off by default and has no effect while tracing is off. To turn it on for everyone, set `strict_auth` to `true` in the managed file.

## Hide a conversation

Run `/langsmith-tracing:mute` in a Cowork task to keep its content out of LangSmith, and `/langsmith-tracing:unmute` to turn it back on. To mute every task by default, set `defaultMuted` to `true`.

## Secret redaction

The plugin strips secrets on your machine before anything is uploaded, so they never reach LangSmith or a replica. Redaction is on by default.

It catches provider API keys, JSON Web Tokens, and PEM private keys, along with common patterns such as `API_KEY=<value>` or a password in a URL. Each match is replaced with `[SECRET_DETECTED]`. For the full rule list, see [Redact secrets from traces](https://docs.langchain.com/langsmith/redact-secrets.md#rules-in-the-preset).

Redaction only matches known credential shapes, so treat it as a safety net rather than a guarantee. Run names, tags, and attachments skip it, and a redacted trace still holds your prompts and file contents. Limit who can read the tracing project.

## Settings

Cowork uses the same settings as Claude Code. For the main ones, see [Settings](https://docs.langchain.com/langsmith/trace-claude-code.md#settings). For every setting, see the [plugin settings](https://github.com/langchain-ai/langsmith-claude-code-plugins#settings).

***

[Connect these docs](https://docs.langchain.com/use-these-docs.md) to your agent of choice via MCP for real-time answers.

[Edit this page on GitHub](https://github.com/langchain-ai/docs/edit/main/src/langsmith/trace-claude-cowork.mdx) or [file an issue](https://github.com/langchain-ai/docs/issues/new/choose).