Send an email

Sends an email design. Polymorphic on test / transactionId:

• test: true → a synchronous one-off TEST delivery of the design’s current (or pinned) body to a single address, with a [TEST] subject prefix. Sends from the Brew default sender unless a verified org-owned domainId is supplied (fromEmail/senderName customize it; an unverified/foreign domain is rejected, never downgraded). Optional variables supply example values for {{ var | fallback }} merge tags — a value wins over the declared fallback. Targets one to address and never creates a Send row. Returns 200 { status: "sent", recipient }.
• transactionId → fire a reusable transactional email object. Domain and design are locked on the object; to (1–50) is required; optional payload supplies merge-tag values. Optional envelope overrides: replyTo, senderName, fromEmail, subject, previewText. Creates a sends row with kind: transactional. Returns 202 { sendId, runId }. Prefer this over leftover inline emailId + domainId + to on a transactional domain.
• 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.

POST /v1/sends

cURL

test

curl --request POST \
  --url https://brew.new/api/v1/sends \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "test": true,
  "emailId": "eml_welcome",
  "subject": "Welcome to Brew",
  "to": "[e-mail]"
}
'

200

Example

{
  "status": "sent",
  "recipient": "[e-mail]"
}

Authorizations

bearerAuthapiKeyAuth

Authorization · string · header · default: Bearer brew_your_api_key · required

Send your Brew API key as Authorization: Bearer brew_xxx.

Headers

Idempotency-Key · string

Optional idempotency key for safe retries. Reusing the same key with the same request body returns the original response for 24 hours.

Required string length: 1 - 100

X-Brand-Id · string

The brand this request acts on. REQUIRED for organization-scoped credentials (otherwise 400 BRAND_ID_REQUIRED — there is no default brand); list ids with GET /v1/brands. Brand-scoped credentials may omit it, and sending a different brand returns 403 BRAND_SCOPE_MISMATCH. A brand outside your organization returns 404 BRAND_NOT_FOUND.

Required string length: 1 - 64

Body

application/json

Option 1

Option 2

Option 3

test · enum<boolean> · required

Available options: true

emailId · string · required

Minimum string length: 1

subject · string · required

Minimum string length: 1

to · string<email> · required

emailVersionId · string

Minimum string length: 1

previewText · string

Inbox preheader for this test send — overrides the design's JSX . Omit to deliver the design's own preview line.

Maximum string length: 200

replyTo · string<email>

domainId · string

OPTIONAL verified sending domain for this test. Omit for the Brew default sender ([e-mail]). Must be a verified domain owned by this org/brand — an unverified or foreign domain is rejected (404/422), never silently downgraded to the Brew default.

Minimum string length: 1

senderName · string

Required string length: 1 - 128

fromEmail · string

Required string length: 1 - 64

variables · object

Example values for {{ var | fallback }} merge tags in the subject, previewText, and body. A supplied value wins over contact fields and the declared fallback; undefined variables render their fallback (or empty). Max 25 entries; keys must match the merge-tag grammar (letter/_/$ start, then word chars/dots/$, max 64 chars); values max 256 chars.

Show child attributes

payload · object

Nested JSON template data for Liquid-mode designs, exposed as trigger.* / payload.*. Flat variables still resolve legacy {{ tag | fallback }} merge tags; send both if a design mixes syntaxes. Live-fire parity on non-Liquid workspaces: scalar keys resolve merge tags (below variables) and nested values are rejected with a 400.

Show child attributes

Response

200

application/json

The TEST send (test: true) was delivered synchronously to the single recipient.

status · enum<string> · required

Available options: sent

recipient · string<email> · required