> ## Documentation Index > Fetch the complete documentation index at: https://help.ciarem.ai/llms.txt > Use this file to discover all available pages before exploring further. # Cancel a broadcast > Abandon the un-sent remainder. The worker checks for a cancel once per chunk, so every chunk that has not started is dropped. Messages already handed to Meta still complete — a message Meta accepted cannot be unsent. Idempotent: cancelling an already terminal broadcast returns it unchanged rather than erroring. ## OpenAPI ````yaml /api-reference/openapi.json post /v1/broadcasts/{broadcast_id}/cancel openapi: 3.1.0 info: title: Ciarem API version: v1 description: > The Ciarem public API. Authenticate every request with an org-bound API key (created in Settings → API keys; Scale plan or free trial) sent as a bearer token: `Authorization: Bearer oak_…`. Compatibility: this is an early, fast-moving API. Most changes are additive (new endpoints, new optional params, new response fields, new enum/string values) — clients must tolerate unknown fields and unknown string values. Every contract change is listed in the changelog at help.ciarem.ai. servers: - url: https://api.ciarem.ai security: - apiKey: [] tags: - name: Account description: The organization behind the API key. - name: Contacts description: People in the CRM — create, read, update, delete. - name: CRM description: 'The shape of the CRM: custom properties and funnel stages.' - name: Conversations description: Read the message history of a conversation. - name: WhatsApp numbers description: The connected numbers a send can go out from. - name: WhatsApp templates description: Message templates, and what each one needs filled before it can be sent. - name: Broadcasts description: Send a template, and follow what happened to every recipient. paths: /v1/broadcasts/{broadcast_id}/cancel: post: tags: - Broadcasts summary: Cancel a broadcast description: >- Abandon the un-sent remainder. The worker checks for a cancel once per chunk, so every chunk that has not started is dropped. Messages already handed to Meta still complete — a message Meta accepted cannot be unsent. Idempotent: cancelling an already terminal broadcast returns it unchanged rather than erroring. operationId: cancel_endpoint_v1_broadcasts__broadcast_id__cancel_post parameters: - name: broadcast_id in: path required: true schema: type: string title: Broadcast Id responses: '200': description: Successful Response content: application/json: schema: $ref: '#/components/schemas/PublicBroadcast' headers: X-RateLimit-Limit: $ref: '#/components/headers/X-RateLimit-Limit' X-RateLimit-Remaining: $ref: '#/components/headers/X-RateLimit-Remaining' X-RateLimit-Reset: $ref: '#/components/headers/X-RateLimit-Reset' '401': description: >- No usable credential: `missing_bearer_token` (no `Authorization: Bearer`) or `invalid_api_key` (unknown or revoked key). content: application/json: schema: $ref: '#/components/schemas/PublicError' '403': description: >- The credential is real but not allowed here: `api_key_required` (a session token rather than an `oak_` key), `scale_plan_required` (a live plan below Scale — upgrade to Scale), `trial_expired` (the free trial ended without a card — subscribe to keep the key working), or `subscription_required` (the subscription is canceled or suspended). content: application/json: schema: $ref: '#/components/schemas/PublicError' '422': description: Validation Error content: application/json: schema: $ref: '#/components/schemas/HTTPValidationError' '429': description: >- Over the organization's request budget (`rate_limited`). `Retry-After` says how many seconds to wait. content: application/json: schema: $ref: '#/components/schemas/PublicError' headers: Retry-After: description: Seconds until the window resets. schema: type: integer X-RateLimit-Limit: $ref: '#/components/headers/X-RateLimit-Limit' X-RateLimit-Remaining: $ref: '#/components/headers/X-RateLimit-Remaining' X-RateLimit-Reset: $ref: '#/components/headers/X-RateLimit-Reset' components: schemas: PublicBroadcast: properties: id: type: string title: Id template_id: type: string title: Template Id template_name: type: string title: Template Name template_language: type: string title: Template Language channel_id: type: string title: Channel Id status: $ref: '#/components/schemas/BroadcastDisplayStatus' requested: type: integer title: Requested sent: type: integer title: Sent failed: type: integer title: Failed pending: type: integer title: Pending origin: type: string title: Origin created_at: type: string format: date-time title: Created At type: object required: - id - template_id - template_name - template_language - channel_id - status - requested - sent - failed - pending - origin - created_at title: PublicBroadcast description: >- A queued template send. Counts are derived from the messages it produced, so they move as the worker fans the batch out; they always sum to `requested`. PublicError: description: An error whose `detail` is a stable, machine-readable code. properties: detail: title: Detail type: string required: - detail title: PublicError type: object HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' type: array title: Detail type: object title: HTTPValidationError BroadcastDisplayStatus: type: string enum: - in_progress - completed - stopped_low_balance - cancelled title: BroadcastDisplayStatus description: >- Derived campaign status shown in the UI. `stopped_low_balance` and `cancelled` mirror the stored state; the other two are computed from the counts (no stored value — chunked async means no single worker knows it sent the last recipient). ValidationError: properties: loc: items: anyOf: - type: string - type: integer type: array title: Location msg: type: string title: Message type: type: string title: Error Type input: title: Input ctx: type: object title: Context type: object required: - loc - msg - type title: ValidationError headers: X-RateLimit-Limit: description: Requests allowed per window, shared across the org's keys. schema: type: integer X-RateLimit-Remaining: description: Requests left in the current window. schema: type: integer X-RateLimit-Reset: description: When the window resets, as a Unix timestamp in seconds. schema: type: integer securitySchemes: apiKey: type: http scheme: bearer description: 'An org API key: `Authorization: Bearer oak_…`.' ````