> ## Documentation Index > Fetch the complete documentation index at: https://docs.zavu.dev/llms.txt > Use this file to discover all available pages before exploring further. # Send broadcast > Start sending the broadcast immediately or schedule for later. Broadcasts go through automated AI content review before sending. If the review passes, the broadcast proceeds. If rejected, use PATCH to edit content, then call POST /retry-review. Reserves the estimated cost from your balance. ## OpenAPI ````yaml /openapi.json post /v1/broadcasts/{broadcastId}/send openapi: 3.0.3 info: title: Zavu Unified Messaging Layer API version: 0.2.0 description: > Unified multi-channel messaging API for Zavu. Supported channels: - **SMS**: Simple text messages - **WhatsApp**: Rich messaging with media, buttons, lists, CTA URL buttons, and templates - **Telegram**: Bot messaging with text, media, and interactive elements - **Email**: Transactional emails via Amazon SES Design goals: - Simple `send()` entrypoint for developers - Project-level authentication via Bearer token - Support for all WhatsApp message types (text, image, video, audio, document, sticker, location, contact, buttons, list, cta_url, reaction, template) - If a non-text message type is sent, WhatsApp channel is used automatically - 24-hour WhatsApp conversation window enforcement - Universal `to` field accepts phone numbers (E.164), email addresses, or numeric chat IDs (Telegram/Instagram) servers: - url: https://api.zavu.dev security: - bearerAuth: [] paths: /v1/broadcasts/{broadcastId}/send: post: summary: Send broadcast description: >- Start sending the broadcast immediately or schedule for later. Broadcasts go through automated AI content review before sending. If the review passes, the broadcast proceeds. If rejected, use PATCH to edit content, then call POST /retry-review. Reserves the estimated cost from your balance. operationId: sendBroadcast parameters: - $ref: '#/components/parameters/BroadcastIdParam' requestBody: required: false content: application/json: schema: $ref: '#/components/schemas/BroadcastSendRequest' examples: immediate: summary: Send immediately value: {} scheduled: summary: Schedule for later value: scheduledAt: '2024-01-15T10:00:00Z' responses: '202': description: Broadcast started or scheduled. content: application/json: schema: $ref: '#/components/schemas/BroadcastResponse' '400': description: Invalid request, no contacts, or broadcast not in valid status. content: application/json: schema: $ref: '#/components/schemas/Error' '401': description: Unauthorized. content: application/json: schema: $ref: '#/components/schemas/Error' '402': description: Insufficient balance. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: insufficient_balance message: 'Insufficient balance. Available: $50.00' details: totalBalance: 50 reservedBalance: 25 availableBalance: 25 '404': description: Broadcast not found. content: application/json: schema: $ref: '#/components/schemas/Error' security: - bearerAuth: [] components: parameters: BroadcastIdParam: name: broadcastId in: path required: true schema: type: string schemas: BroadcastSendRequest: type: object properties: scheduledAt: type: string format: date-time description: Schedule for future delivery. Omit to send immediately. BroadcastResponse: type: object required: - broadcast properties: broadcast: $ref: '#/components/schemas/Broadcast' Error: type: object required: - code - message properties: code: type: string example: invalid_request message: type: string example: Phone number is invalid details: type: object additionalProperties: true Broadcast: type: object required: - id - name - status - channel - messageType - totalContacts - createdAt properties: id: type: string example: brd_abc123 name: type: string status: $ref: '#/components/schemas/BroadcastStatus' channel: $ref: '#/components/schemas/BroadcastChannel' messageType: $ref: '#/components/schemas/BroadcastMessageType' text: type: string content: $ref: '#/components/schemas/BroadcastContent' senderId: type: string emailSubject: type: string totalContacts: type: integer description: Total number of contacts in the broadcast. pendingCount: type: integer sendingCount: type: integer deliveredCount: type: integer failedCount: type: integer estimatedCost: type: number nullable: true description: Estimated total cost in USD. reservedAmount: type: number nullable: true description: Amount reserved from balance in USD. actualCost: type: number nullable: true description: Actual cost so far in USD. scheduledAt: type: string format: date-time startedAt: type: string format: date-time completedAt: type: string format: date-time metadata: type: object additionalProperties: type: string createdAt: type: string format: date-time updatedAt: type: string format: date-time reviewResult: type: object nullable: true description: AI content review result. properties: score: type: number description: >- Content safety score from 0.0 to 1.0, where 1.0 is completely safe. categories: type: array items: type: string description: Policy categories violated, if any. reasoning: type: string description: Explanation of the review decision. reviewedAt: type: string format: date-time flaggedContent: type: array items: type: string nullable: true description: Problematic text fragments, if any. reviewAttempts: type: integer nullable: true description: Number of review attempts (max 3). BroadcastStatus: type: string description: Current status of the broadcast. enum: - draft - pending_review - approved - rejected - escalated - rejected_final - scheduled - sending - paused - completed - cancelled - failed BroadcastChannel: type: string description: >- Broadcast delivery channel. Use 'smart' for per-contact intelligent routing. enum: - smart - sms - sms_oneway - whatsapp - telegram - email - instagram - voice BroadcastMessageType: type: string description: Type of message for broadcast. enum: - text - image - video - audio - document - template BroadcastContent: type: object description: Content for non-text broadcast message types. properties: mediaUrl: type: string description: URL of the media file. mediaId: type: string description: Media ID if already uploaded. mimeType: type: string description: MIME type of the media. filename: type: string description: Filename for documents. templateId: type: string description: Template ID for template messages. templateVariables: type: object description: >- Default body variables (can be overridden per contact). Keys are positions (1, 2, ...). additionalProperties: type: string templateButtonVariables: type: object description: >- Default button variables for dynamic URL/OTP buttons. Keys are the button index (0, 1, 2). Per-contact values override these. additionalProperties: type: string securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: JWT ````