> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hill90.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Cancel all pending messages

> Marks all pending messages in the thread as error with message
'Cancelled by user'. Bumps seq for SSE visibility.




## OpenAPI

````yaml /ai-app/openapi.yaml post /chat/threads/{id}/cancel
openapi: 3.0.3
info:
  title: Hill90 API
  description: Hill90 platform API — agent management and lifecycle operations.
  version: 0.1.0
servers:
  - url: /
    description: Relative (behind Traefik reverse proxy)
security: []
paths:
  /chat/threads/{id}/cancel:
    parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
          format: uuid
    post:
      summary: Cancel all pending messages
      description: |
        Marks all pending messages in the thread as error with message
        'Cancelled by user'. Bumps seq for SSE visibility.
      responses:
        '200':
          description: Cancellation result
          content:
            application/json:
              schema:
                type: object
                properties:
                  cancelled:
                    type: integer
                    description: Number of messages cancelled
        '404':
          description: Thread not found or not a participant
      security:
        - bearerAuth: []
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT

````