> ## Documentation Index > Fetch the complete documentation index at: https://docs.brew.new/llms.txt > Use this file to discover all available pages before exploring further. # Send an email > Sends an email design. Polymorphic on the `test` flag: - **`test: true`** → a synchronous one-off TEST delivery of the design’s current (or pinned) body to a single address. Forces the Brew default sender (no verified domain needed), targets one `to` address, and never creates a `Send` row. Returns **`200`** `{ status: "sent", recipient }`. - **default / `test: false`** → a campaign send combining the design (`emailId`, optionally pinned to `emailVersionId`), a verified `domainId`, and a target — a saved `audienceId` OR inline `to` (a single email or an array, max 50) — into one delivery event. The same design can be sent unlimited times; every call mints a new send. Returns **`202`** `{ sendId, runId }` — poll via `GET /v1/analytics/sends?sendId=`. Campaign target — provide EXACTLY ONE of `audienceId` or `to`. Inline recipients face the same unsubscribe/suppression gate and per-recipient quota as audience sends. For per-recipient event-driven delivery, publish an automation and fire its trigger (`POST /v1/automations/triggers/{triggerEventId}/fire`). Brand scoping: resources (`emailId`, `domainId`, `audienceId`) living in a different brand surface as `404` so the API never confirms cross-brand existence. ## OpenAPI ````yaml /api-reference/openapi-public-v1.yaml post /v1/sends openapi: 3.1.0 info: title: Brew Public API v1 version: 1.0.0 description: >- Generated from the Brew app Zod contracts (`lib//contracts.ts`). This file is the source of truth for the public API documentation. ## Resource paths Identity lives in the URL path (`/v1/analytics/sends/{sendId}`) — never in a query param or request body. Collections are plural top-level segments (`/v1/emails`); query params exist only for collection pagination + simple filters. Relationships are sub-resources (`/v1/emails/{emailId}/sends`), and non-CRUD operations are explicit action sub-paths (`/v1/automations/{automationId}/test`). ## Response envelopes - Lists: `{ data: Row[], pagination: { limit, cursor: string | null, hasMore } }` — loop `while (cursor !== null)`. - Get-one and writes: the bare resource (creates return `201`; async sends `202`). - Deletes: `{ , deleted: boolean }` — idempotent (already-gone ids resolve with `deleted: false`). - Errors: `{ error: { code, type, message, param?, suggestion, docs } }` — branch on the stable `code`. - ONE exception: `POST /v1/automations/triggers/{triggerEventId}/fire` responds with the legacy fire envelope `{ success, status, code, message, receivedAt, details }` (shared with internal webhook infrastructure). ## Brand scoping API keys are always scoped to a specific brand. The brand is resolved from the key on every request. **No public endpoint accepts a `brandId` field** in its request body or query string — sending one returns `400 INVALID_REQUEST`. Resources that exist in a different brand surface as `404` (never `403`), so the API does not leak cross-brand existence. `GET /v1/templates` is organization-wide and not constrained to the key brand. Brands themselves are managed in the Brew dashboard. ## Idempotency Send an `Idempotency-Key` header (≤ 100 chars) on any POST your code might retry. Same key + same body within 24h returns the original response; same key + different body returns `409 IDEMPOTENCY_CONFLICT`. contact: name: Brew Support url: https://docs.brew.new email: support@brew.new servers: - url: https://brew.new/api description: Production - url: http://localhost:3000/api description: Local development security: - bearerAuth: [] - apiKeyAuth: [] tags: - name: Emails description: >- Email designs and sending. Generate a design with the Brew email agent, edit, version, restore — then send it: `POST /v1/sends` delivers a design to a target (a saved audience, an inline list, or a single address) via a verified domain, and `POST /v1/sends/test` fires a one-off test. Sending is not campaign-specific. Send reads (list, status, per-send event feeds) live under Analytics (`/v1/analytics/sends`). - name: Analytics description: >- Read-only cross-resource analytics: lifetime per-campaign KPIs, windowed automation performance, the unified event feed, send reads (`/v1/analytics/sends`), and the fired-trigger audit log (`/v1/analytics/trigger-instances`). - name: Automations description: >- Automation graphs — deterministic create from explicit `nodes` + `connections`, update, version, publish / unpublish, test. Includes trigger event definitions + the fire endpoint (`/v1/automations/triggers`) and run history (`/v1/automations/runs`). - name: Contacts description: Create, search, patch, and delete contacts. Email is the primary key. - name: Contact Fields description: List, create, and delete custom contact field definitions. - name: Audiences description: Saved contact filter sets — a recipient target for sends. - name: Domains description: 'Sending domains: add, read DNS records, verify, configure sender defaults.' - name: Templates description: Public template gallery (read-only) usable as generation references. - name: Brand description: The single brand bound to the API key. - name: Chats description: >- Read a brand-scoped digest of a Brew chat — referenced emails/automations/triggers + a trimmed transcript — so an external agent can resume the conversation. - name: Meta description: >- Public discovery surface (no auth): the machine-readable API catalog (`/v1/help`). paths: /v1/sends: post: tags: - Emails summary: Send an email description: >- Sends an email design. Polymorphic on the `test` flag: - **`test: true`** → a synchronous one-off TEST delivery of the design’s current (or pinned) body to a single address. Forces the Brew default sender (no verified domain needed), targets one `to` address, and never creates a `Send` row. Returns **`200`** `{ status: "sent", recipient }`. - **default / `test: false`** → a campaign send combining the design (`emailId`, optionally pinned to `emailVersionId`), a verified `domainId`, and a target — a saved `audienceId` OR inline `to` (a single email or an array, max 50) — into one delivery event. The same design can be sent unlimited times; every call mints a new send. Returns **`202`** `{ sendId, runId }` — poll via `GET /v1/analytics/sends?sendId=`. Campaign target — provide EXACTLY ONE of `audienceId` or `to`. Inline recipients face the same unsubscribe/suppression gate and per-recipient quota as audience sends. For per-recipient event-driven delivery, publish an automation and fire its trigger (`POST /v1/automations/triggers/{triggerEventId}/fire`). Brand scoping: resources (`emailId`, `domainId`, `audienceId`) living in a different brand surface as `404` so the API never confirms cross-brand existence. operationId: createSend parameters: - name: Idempotency-Key in: header required: false description: >- Optional idempotency key for safe retries. Reusing the same key with the same request body returns the original response for 24 hours. schema: type: string minLength: 1 maxLength: 100 example: api-request-2026-04-08-001 requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/SendEmailRequest' examples: test: summary: One-off test to a single address (sync 200) value: test: true emailId: eml_welcome subject: Welcome to Brew to: qa@acme.com now: summary: Send the latest version to an audience now value: emailId: eml_welcome domainId: kx7bkh53hasmfeh5kd7sqgykt187g8ww subject: Welcome to Brew audienceId: aud_subscribers scheduledPinned: summary: Schedule a pinned version for later value: emailId: eml_welcome emailVersionId: emv_welcome_v2 domainId: kx7bkh53hasmfeh5kd7sqgykt187g8ww subject: Welcome to Brew previewText: Get started in 2 minutes. audienceId: aud_subscribers scheduledAt: '2099-01-01T00:00:00.000Z' inline: summary: Send to inline recipients value: emailId: eml_welcome domainId: kx7bkh53hasmfeh5kd7sqgykt187g8ww subject: Welcome to Brew to: - founder@acme.com - design@acme.com responses: '200': description: >- The TEST send (`test: true`) was delivered synchronously to the single recipient. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. X-RateLimit-Limit: schema: type: integer description: Requests allowed in the current rolling rate limit window. example: 100 required: true description: Requests allowed in the current rolling rate limit window. X-RateLimit-Remaining: schema: type: integer description: Requests remaining in the current rolling rate limit window. example: 99 required: true description: Requests remaining in the current rolling rate limit window. X-RateLimit-Reset: schema: type: integer description: >- Unix timestamp in seconds for when the rolling window fully resets. example: 1712592360 required: true description: >- Unix timestamp in seconds for when the rolling window fully resets. content: application/json: schema: $ref: '#/components/schemas/SendEmailTestResponse' example: status: sent recipient: qa@acme.com '202': description: The campaign send was accepted, queued or scheduled. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. X-RateLimit-Limit: schema: type: integer description: Requests allowed in the current rolling rate limit window. example: 100 required: true description: Requests allowed in the current rolling rate limit window. X-RateLimit-Remaining: schema: type: integer description: Requests remaining in the current rolling rate limit window. example: 99 required: true description: Requests remaining in the current rolling rate limit window. X-RateLimit-Reset: schema: type: integer description: >- Unix timestamp in seconds for when the rolling window fully resets. example: 1712592360 required: true description: >- Unix timestamp in seconds for when the rolling window fully resets. content: application/json: schema: $ref: '#/components/schemas/SendsPostResponse' example: status: queued sendId: snd_8fK2mQ4p runId: wrun_abc '400': description: >- Invalid body — missing required field (`emailId`, `domainId`, `subject`), neither or both of `audienceId`/`to`, more than 50 inline `to` addresses, a past `scheduledAt`, or an unknown key. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. content: application/json: schema: $ref: '#/components/schemas/ApiErrorEnvelope' example: error: code: INVALID_REQUEST type: invalid_request message: Request validation failed. suggestion: Fix the field reported in `param` and retry. docs: https://docs.brew.new/api-reference/api/errors param: audienceId '401': description: The API key was missing, invalid, or revoked. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. content: application/json: schema: $ref: '#/components/schemas/ApiErrorEnvelope' example: error: code: INVALID_API_KEY type: authentication_error message: The provided API key is invalid. suggestion: Check the API key format and retry with a valid active key. docs: https://docs.brew.new/api-reference/api/authentication '403': description: The caller does not have the required `sends` permission. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. content: application/json: schema: $ref: '#/components/schemas/ApiErrorEnvelope' example: error: code: INSUFFICIENT_PERMISSIONS type: authorization_error message: The caller does not have the required permission. suggestion: Use an API key or session with the required permission. docs: https://docs.brew.new/api-reference/api/authentication param: sends '404': description: >- The referenced email, domain, or audience was not found in the API-key brand. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. content: application/json: schema: $ref: '#/components/schemas/ApiErrorEnvelope' example: error: code: EMAIL_NOT_FOUND type: not_found message: The requested email 'eml_x' was not found. suggestion: List designs with GET /v1/emails. docs: https://docs.brew.new/api-reference/api/errors param: emailId '409': description: The same `Idempotency-Key` was reused with a different request body. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. content: application/json: schema: $ref: '#/components/schemas/ApiErrorEnvelope' example: error: code: IDEMPOTENCY_CONFLICT type: conflict message: >- The same idempotency key was reused with a different request payload. suggestion: Reuse the original payload or send a new idempotency key. docs: https://docs.brew.new/api-reference/api/idempotency '422': description: The referenced resource exists but is not ready. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. content: application/json: schema: $ref: '#/components/schemas/ApiErrorEnvelope' examples: domainNotReady: summary: Domain not verified value: error: code: DOMAIN_NOT_READY type: invalid_request message: >- The requested domain 'dom_x' is not verified for sending. suggestion: >- Verify the domain with POST /v1/domains/{domainId}/verify, or pick a sendable one from GET /v1/domains?sendableOnly=true. docs: https://docs.brew.new/api-reference/api/errors param: domainId emailNotReady: summary: Design still generating value: error: code: EMAIL_NOT_READY type: invalid_request message: The requested email 'eml_x' is not ready to send. suggestion: >- Wait for generation to finish (GET /v1/emails?emailId= → status: "complete"). docs: https://docs.brew.new/api-reference/api/errors param: emailId '429': description: The request hit the rolling rate limit window. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. X-RateLimit-Limit: schema: type: integer description: Requests allowed in the current rolling rate limit window. example: 100 required: true description: Requests allowed in the current rolling rate limit window. X-RateLimit-Remaining: schema: type: integer description: Requests remaining in the current rolling rate limit window. example: 99 required: true description: Requests remaining in the current rolling rate limit window. X-RateLimit-Reset: schema: type: integer description: >- Unix timestamp in seconds for when the rolling window fully resets. example: 1712592360 required: true description: >- Unix timestamp in seconds for when the rolling window fully resets. Retry-After: schema: type: integer description: Seconds to wait before retrying the request. example: 42 required: true description: Seconds to wait before retrying the request. content: application/json: schema: $ref: '#/components/schemas/ApiErrorEnvelope' example: error: code: RATE_LIMITED type: rate_limit message: Too many requests. suggestion: Wait for the retry window before sending another request. docs: https://docs.brew.new/api-reference/api/rate-limits retryAfter: 42 '500': description: Unexpected internal error. headers: x-request-id: schema: type: string description: >- Unique request identifier. Share this with support when debugging a request. example: req_8cac13fd94e6420cacdd75a1aa403a28 required: true description: >- Unique request identifier. Share this with support when debugging a request. content: application/json: schema: $ref: '#/components/schemas/ApiErrorEnvelope' example: error: code: INTERNAL_ERROR type: internal_error message: An unexpected error occurred. suggestion: Retry the request. If it keeps failing, contact support. docs: https://docs.brew.new/api-reference/api/errors components: schemas: SendEmailRequest: anyOf: - type: object properties: test: type: boolean enum: - true emailId: type: string minLength: 1 emailVersionId: type: string minLength: 1 subject: type: string minLength: 1 previewText: type: string maxLength: 50 to: type: string format: email replyTo: type: string format: email required: - test - emailId - subject - to additionalProperties: false - type: object properties: test: type: boolean enum: - false emailId: type: string minLength: 1 emailVersionId: type: string minLength: 1 subject: type: string minLength: 1 previewText: type: string maxLength: 50 replyTo: type: string description: >- Reply-to address. Accepts a bare email (`a@b.com`) or the display-name form (`Name `). domainId: type: string minLength: 1 audienceId: type: string minLength: 1 to: anyOf: - type: string format: email - type: array items: type: string format: email minItems: 1 maxItems: 50 scheduledAt: type: string format: date-time required: - emailId - subject - domainId additionalProperties: false SendEmailTestResponse: type: object properties: status: type: string enum: - sent recipient: type: string format: email required: - status - recipient additionalProperties: false SendsPostResponse: type: object properties: status: type: string enum: - queued - scheduled sendId: type: string minLength: 1 runId: type: string minLength: 1 scheduledAt: type: string format: date-time required: - status - sendId - runId additionalProperties: false ApiErrorEnvelope: type: object properties: error: type: object properties: code: type: string minLength: 1 type: type: string enum: - authentication_error - authorization_error - invalid_request - not_found - not_implemented - conflict - rate_limit - payment_required - service_unavailable - internal_error message: type: string minLength: 1 param: type: string minLength: 1 suggestion: type: string minLength: 1 docs: type: string format: uri retryAfter: type: integer minimum: 0 details: type: object additionalProperties: {} required: - code - type - message - suggestion - docs required: - error securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: API key description: 'Send your Brew API key as `Authorization: Bearer brew_xxx`.' x-default: Bearer brew_your_api_key apiKeyAuth: type: apiKey in: header name: X-API-Key description: 'Send your Brew API key as `X-API-Key: brew_xxx`.' x-default: brew_your_api_key ````