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

# Cancel a queued call

> Cancel a call that hasn't started yet



## OpenAPI

````yaml /api-reference/openapi.json post /v1/calls/{call_id}/cancel
openapi: 3.0.3
info:
  title: TopCalls Voice API
  description: >
    TopCalls Voice Gateway API for creating and managing AI-powered phone calls.


    ## Authentication


    All API requests require authentication. Include your API key in the
    `Authorization` header:


    ```

    Authorization: Bearer tc_live_xxxxx

    ```


    ## Rate Limits


    Direct call creation via `POST /v1/calls` is limited to your account's

    `max_calls_per_minute` setting (default: 20) per minute. Exceeding it
    returns

    `429 Too Many Requests` with a `Retry-After` header.

    All endpoints are additionally subject to a flat limit of 120 requests per

    minute per account (all methods).


    On a `429`, wait for the number of seconds in the `Retry-After` header, then

    retry the same request. For automated clients, back off progressively on

    repeated `429`s. Limits are per account and are shared by all API keys.


    ## Error Format


    All errors follow RFC 7807 Problem+JSON format:


    ```json

    {
      "type": "https://api.topcalls.ai/errors/insufficient_quota",
      "title": "Insufficient Quota",
      "status": 402,
      "detail": "You need 5 minutes but have 3.5 remaining"
    }

    ```
  version: 1.0.0
  contact:
    name: TopCalls Support
    url: https://topcalls.ai
  license:
    name: Proprietary
servers:
  - url: https://api.topcalls.ai
    description: Production
security: []
tags:
  - name: Calls
    description: Create and manage phone calls
  - name: Phone Numbers
    description: Manage phone numbers and carriers
  - name: Account
    description: Account information and usage
  - name: Webhooks
    description: Webhook configuration and events
  - name: Configuration
    description: Available AI models, voices, and platform capabilities
paths:
  /v1/calls/{call_id}/cancel:
    post:
      tags:
        - Calls
      summary: Cancel a queued call
      description: Cancel a call that hasn't started yet
      operationId: cancelCall
      parameters:
        - name: call_id
          in: path
          required: true
          description: Call UUID
          schema:
            type: string
            format: uuid
        - $ref: '#/components/parameters/IdempotencyKeyHeader'
      responses:
        '200':
          description: Call cancelled successfully
          content:
            application/json:
              schema:
                type: object
                properties:
                  ok:
                    type: boolean
                    example: true
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          description: Call not found
          content:
            application/problem+json:
              schema:
                $ref: '#/components/schemas/Problem'
        '409':
          $ref: '#/components/responses/IdempotencyConflict'
      security:
        - bearerAuth: []
components:
  parameters:
    IdempotencyKeyHeader:
      name: Idempotency-Key
      in: header
      required: false
      description: |
        Optional client-supplied idempotency key. When present, the gateway
        caches the response for 24 hours and returns the same response on
        retried requests with the same key (account-scoped). Safe for
        retries on network blips. Format: 8-255 ASCII characters from
        `[A-Za-z0-9_-]`.
      schema:
        type: string
        minLength: 8
        maxLength: 255
        pattern: ^[A-Za-z0-9_-]+$
        example: a1b2c3d4-e5f6-7890-abcd-ef0123456789
  responses:
    Unauthorized:
      description: Unauthorized (missing or invalid API key)
      content:
        application/problem+json:
          schema:
            $ref: '#/components/schemas/Problem'
          example:
            status: 401
            title: Unauthorized
            detail: Invalid or missing API key
    Forbidden:
      description: Forbidden (missing required scope)
      content:
        application/problem+json:
          schema:
            $ref: '#/components/schemas/Problem'
          example:
            status: 403
            title: Forbidden
            detail: 'Missing required scope: calls:write'
    IdempotencyConflict:
      description: |
        Another request with the same Idempotency-Key is currently being
        processed. Retry once it completes.
      content:
        application/problem+json:
          schema:
            $ref: '#/components/schemas/Problem'
          example:
            status: 409
            title: 'Conflict: request in-flight'
            detail: >-
              Another request with the same Idempotency-Key is currently being
              processed.
  schemas:
    Problem:
      type: object
      required:
        - status
        - title
      properties:
        type:
          type: string
          format: uri
          description: Error type URI
        title:
          type: string
          description: Error title
        status:
          type: integer
          description: HTTP status code
        detail:
          type: string
          description: Human-readable error detail
        code:
          type: string
          description: >
            Machine-readable error code for programmatic handling. Present on

            errors that carry a stable identifier (e.g. `PROMPT_SAFETY_FRAUD`,

            `job_not_found`, `too_many_ids`, `no_matches`). Distinct from the

            per-field `errors[].code` used for validation failures. Scenario-

            specific — see each endpoint's response examples for the exact
            value.
        instance:
          type: string
          format: uuid
          description: Request instance ID
        errors:
          type: array
          description: Validation errors (for 400 responses)
          items:
            type: object
            properties:
              path:
                type: string
                description: Field path (e.g., "phone_number", "metadata.from_number")
              message:
                type: string
                description: Error message
              code:
                type: string
                description: Error code (e.g., "invalid_string", "custom")
        details:
          type: string
          description: Additional error details (for provider errors)
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: |
        Use `Authorization: Bearer tc_live_xxxxx`

````