> ## Documentation Index > Fetch the complete documentation index at: https://segmentflow.ai/docs/llms.txt > Use this file to discover all available pages before exploring further. # Create broadcast > Create a Broadcast for a Segment. Inline content creates a saved Email Template first; templateId reuses an existing Template. Set send=true to send immediately, or combine send=true with scheduledAt to schedule. ## OpenAPI ````yaml /api-reference/openapi.json post /api/v1/broadcasts openapi: 3.0.3 info: title: SegmentFlow.ai API description: Unified SegmentFlow.ai API documentation version: 1.0.0 servers: - url: http://localhost:3001 description: Local development - url: https://api-staging.segmentflow.ai description: Staging - url: https://api.segmentflow.ai description: Production security: - apiKeyAuth: [] tags: - name: Profiles description: Profiles (Contacts) - name: Events description: Server-side business event tracking - name: Assets description: Assets - name: BackgroundJobs description: Background job progress - name: Brand-Kit description: Brand kits - name: Catalog-Products description: Catalog products - name: Templates description: Templates - name: Broadcasts description: Broadcasts - name: Segments description: Segments - name: Journeys description: Journeys - name: Emails description: Email sends paths: /api/v1/broadcasts: post: tags: - Broadcasts summary: Create broadcast description: >- Create a Broadcast for a Segment. Inline content creates a saved Email Template first; templateId reuses an existing Template. Set send=true to send immediately, or combine send=true with scheduledAt to schedule. operationId: Broadcasts_Create requestBody: content: application/json: schema: type: object properties: segmentId: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ segmentKey: type: string minLength: 1 maxLength: 120 from: description: >- Sender email address. Friendly names may use "Name ". type: string minLength: 1 maxLength: 320 subject: type: string minLength: 1 maxLength: 998 replyTo: anyOf: - type: string format: email pattern: >- ^(?!\.)(?!.*\.\.)([A-Za-z0-9_'+\-\.]*)[A-Za-z0-9_+-]@([A-Za-z0-9][A-Za-z0-9\-]*\.)+[A-Za-z]{2,}$ - minItems: 1 maxItems: 10 type: array items: type: string format: email pattern: >- ^(?!\.)(?!.*\.\.)([A-Za-z0-9_'+\-\.]*)[A-Za-z0-9_+-]@([A-Za-z0-9][A-Za-z0-9\-]*\.)+[A-Za-z]{2,}$ html: type: string minLength: 1 text: type: string name: type: string minLength: 1 maxLength: 200 topicId: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ subscriptionGroupId: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ templateId: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ templateKey: type: string minLength: 1 maxLength: 120 send: default: false type: boolean scheduledAt: type: string minLength: 1 responses: '201': description: Default Response content: application/json: schema: type: object properties: id: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ description: Broadcast id. required: - id additionalProperties: false '400': description: Default Response content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '401': description: Default Response content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '403': description: Default Response content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '404': description: Default Response content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '409': description: Default Response content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '500': description: Default Response content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' components: schemas: ErrorResponse: type: object properties: errorCode: $ref: '#/components/schemas/SegmentflowErrorCode' description: >- Stable machine-readable error code. SDKs map this to typed exception classes. example: TEMPLATE_NAME_EXISTS message: type: string description: >- Human-readable error message. May change between releases; do not parse. example: Template name 'Hello' already exists in this organization. details: description: >- Optional structured detail. `issues` carries per-field validation problems; other keys are reserved. type: object properties: issues: type: array items: $ref: '#/components/schemas/ErrorIssue' additionalProperties: description: Any JSON value. nullable: true x-stainless-any: true required: - errorCode - message additionalProperties: false description: 'Canonical error envelope (ADR-0008): `{ errorCode, message, details? }`.' SegmentflowErrorCode: type: string enum: - BAD_REQUEST - UNAUTHORIZED - FORBIDDEN - NOT_FOUND - CONFLICT - GONE - UNPROCESSABLE_ENTITY - TOO_MANY_REQUESTS - VALIDATION_ERROR - INTERNAL_ERROR - NOT_IMPLEMENTED - SERVICE_UNAVAILABLE - DATABASE_ERROR - IDEMPOTENCY_KEY_TOO_LONG - IDEMPOTENCY_KEY_REUSED - IDEMPOTENCY_IN_FLIGHT - JOURNEY_NOT_FOUND - JOURNEY_WRONG_ENTRY_NODE - JOURNEY_MISSING_RECIPIENT_EMAIL - JOURNEY_MISSING_REQUIRED_VARIABLES - JOURNEY_RECIPIENT_ERASED - JOURNEY_RUN_NOT_FOUND - BROADCAST_NOT_FOUND - BROADCAST_SCHEDULING_NOT_IMPLEMENTED - BROADCAST_INVALID_STATE - BROADCAST_SEND_NOT_ALLOWED - PREPARED_SEND_NOT_FOUND - PREPARED_SEND_EXPIRED - PREPARED_SEND_CROSS_USER - PREPARED_SEND_CORRUPT - PREPARED_SEND_CONCURRENT_REDEEM - PREPARED_SEND_VALIDATION_FAILED - TEMPLATE_NOT_FOUND - TEMPLATE_NAME_EXISTS - PROFILE_NOT_FOUND - PROFILE_SUBSCRIPTION_GROUP_NOT_FOUND - PROFILE_TRAITS_WRITE_UNSUPPORTED - MISSING_CREDENTIAL - INVALID_API_KEY - INVALID_OAUTH_TOKEN - AMBIGUOUS_CREDENTIAL - INSUFFICIENT_SCOPE - MULTIPLE_CREDENTIALS_PRESENT - BEARER_CREDENTIAL_REMOVED - SESSION_ROLE_INSUFFICIENT - API_KEY_SCOPE_INSUFFICIENT - BILLING_DISABLED - BILLING_NOT_CONFIGURED description: >- Stable machine-readable error code. SDK codegen maps these to typed exception classes. ErrorIssue: type: object properties: path: anyOf: - type: string - type: array items: anyOf: - type: string - type: number description: >- Where in the request the issue occurred. String for simple paths; array for nested paths. example: name code: type: string description: >- Stable, machine-readable kind of issue (e.g. 'required', 'invalid_type'). example: duplicate message: type: string description: Human-readable description of the issue. example: Template name already exists in this organization. required: - path - code - message additionalProperties: false description: A single validation issue inside an error response's `details.issues[]`. securitySchemes: apiKeyAuth: type: apiKey in: header name: x-api-key description: Unified API key for server-side SDK and API integrations ````