> ## 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.

# Record a user event

> Record a user event (e.g. thumbs up/down, selected text) attached to a trace. Predefined event types validate against their schemas; custom event types pass through `trackEventRESTParamsValidatorSchema`.



## OpenAPI

````yaml POST /api/events/track
openapi: 3.1.0
info:
  title: LangWatch API
  version: 1.0.0
  description: LangWatch openapi spec
servers:
  - url: https://app.langwatch.ai
security:
  - project_api_key: []
paths:
  /api/events/track:
    post:
      description: >-
        Record a user event (e.g. thumbs up/down, selected text) attached to a
        trace. Predefined event types validate against their schemas; custom
        event types pass through `trackEventRESTParamsValidatorSchema`.
      operationId: postApiEventsTrack
      parameters: []
      responses:
        '200':
          description: Event tracked
          content:
            application/json:
              schema:
                type: object
                properties:
                  message:
                    type: string
                    const: Event tracked
                required:
                  - message
        '400':
          description: Invalid event payload
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    type: string
                  message:
                    type: string
                required:
                  - error
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    type: string
                  message:
                    type: string
                required:
                  - error
        '422':
          description: Unprocessable Entity
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    type: string
                  message:
                    type: string
                required:
                  - error
        '500':
          description: Internal Server Error
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    type: string
                  message:
                    type: string
                required:
                  - error
components:
  securitySchemes:
    project_api_key:
      type: apiKey
      in: header
      name: X-Auth-Token
      description: >-
        Project API key for sending traces and accessing project-scoped
        resources. Format: sk-lw-... (no underscore). Obtain one by creating a
        project via the Admin API or the LangWatch UI.

````