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

# Cancel an AI Phone Call with the API

> Cancel a queued Simple AI outbound phone call before it is placed, using the call's identifier from the create call response.

Only calls with status `enqueued` can be cancelled. A call that has already started or finished returns `409 Conflict`. Cancelling a call that is already cancelled succeeds, so the request is safe to retry.

See the [call object guide](/call-object#status) for the full status lifecycle.


## OpenAPI

````yaml POST /calls/{uuid}/cancel
openapi: 3.1.0
info:
  title: Public API v1
  description: >-
    Public API v1 requiring API keys.


    **Timestamps:** All datetime fields in API responses are returned in UTC
    using ISO 8601 format (e.g., `2024-01-15T14:30:00Z`). When filtering by date
    parameters, provide timestamps in ISO 8601 format.
  version: 0.1.0
servers:
  - url: https://api.usesimple.ai/api/v1
    description: Production API Server
security: []
paths:
  /calls/{uuid}/cancel:
    post:
      tags:
        - Calls
      summary: Cancel Call
      description: >-
        Cancel a call that has not started yet.

        Only calls with status `enqueued` can be cancelled. Cancelling a call
        that is already cancelled succeeds.
      operationId: cancel_call_calls__uuid__cancel_post
      parameters:
        - name: uuid
          in: path
          required: true
          schema:
            type: string
            format: uuid
            title: Uuid
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CallResponse'
              example:
                success: true
                status: cancelled
                uuid: 346fe020-e8c2-4abe-9d40-a4992b016bd6
        '401':
          description: Missing or invalid API key
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PublicApiError'
        '404':
          description: Call not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PublicApiError'
        '409':
          description: The call has already started or finished
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PublicApiError'
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PublicApiError'
      security:
        - APIKeyHeader: []
components:
  schemas:
    CallResponse:
      properties:
        success:
          type: boolean
          title: Success
        status:
          type: string
          enum:
            - enqueued
            - cancelled
          title: Status
          description: '`enqueued` when a call is created, `cancelled` when it is cancelled'
        uuid:
          type: string
          format: uuid
          title: Uuid
          description: The call's identifier. Use it with the other call endpoints.
      type: object
      required:
        - success
        - status
        - uuid
      title: CallResponse
    PublicApiError:
      type: object
      required:
        - status
        - success
        - error
        - errors
      properties:
        status:
          type: string
          const: error
        success:
          type: boolean
          const: false
        error:
          type: string
        errors:
          type: array
          items:
            type: string
      title: Public API Error
  securitySchemes:
    APIKeyHeader:
      type: http
      scheme: bearer
      description: 'Your API key, sent as `Authorization: Bearer YOUR_API_KEY`'

````

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