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

> ## Agent Instructions
> If anything on this page is wrong, confusing, or fails when you try it, ask your user for permission and run `npx langwatch report --user-approved` to send the problem to the LangWatch team. No login is needed and secrets are redacted locally. `npx langwatch report --help` has the details.

# Overview

> Learn how annotations enhance trace review, labeling, and evaluation workflows for more reliable AI agent testing.

## Intro

With the Annotations API, you can annotate traces with additional information. This is useful if you want to add additional information to a trace, such as a comment or a thumbs up/down reaction.

## Authentication

To make a call to the Annotations API, you will need to pass through your LangWatch API key in the header as `X-Auth-Token`. Your API key can be found on the setup page under settings.

### Allowed Methods

* `GET /api/v1/annotations` - Get a list of annotations
* `GET /api/v1/annotations/:id` - Get a single annotation
* `DELETE /api/v1/annotations/:id` - Delete a single annotation
* `PATCH /api/v1/annotations/:id` - Update a single annotation
* `GET /api/v1/annotations/trace/:id` - Get the annotations for a single trace
* `POST /api/v1/annotations/trace/:id` - Create annotations for traces to support domain labeling, evaluation scoring, and agent testing workflows.

#### Annotation queues

Annotation queues have no REST endpoints yet. To send traces to a queue from code, create an automation with the `ADD_TO_ANNOTATION_QUEUE` action ([Triggers API](https://langwatch.ai/docs/api-reference/triggers/overview.md)); to read queues and their items, query the `annotation_queues` and `annotation_queue_items` views with [LangWatchQL](https://langwatch.ai/docs/api-reference/query/overview.md). See [Annotation queues](https://langwatch.ai/docs/annotations/queues.md#from-code).


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