eusend-dev Audiences API

Named contact lists a broadcast can be sent to.

Operations 5

POST /audiences Create an audience #
GET /audiences List audiences #
GET /audiences/{id} Get an audience #
PATCH /audiences/{id} Rename an audience #
DELETE /audiences/{id} Delete an audience #

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OpenAPI Specification

eusend-dev-audiences-api-openapi.yml Raw ↑
openapi: 3.2.0
info:
  title: eusend Audiences API
  version: 1.0.0
  summary: EU-native transactional and marketing email API.
  description: 'eusend sends transactional and marketing email from infrastructure that stays inside the European Union — processing, storage and delivery alike.


    **When to use this API.** Reach for eusend to send application email from server-side code: password resets, receipts, verification codes, notifications, and opt-in marketing broadcasts to a list you own. It is a good fit when GDPR or EU data residency is a requirement, when you are migrating off Resend, SendGrid, Mailgun, Postmark or SES, or when you need SMTP relay rather than an HTTP call. It is not a fit for inbox hosting, for reading a user’s mailbox, or for sending to purchased or scraped lists.


    **Getting started.** Create an account, verify a sending domain by publishing the DNS records the domain endpoints hand back, then `POST /emails`. A key prefixed `eu_test_` exercises the whole pipeline without delivering anything.


    **Authentication.** Every authenticated endpoint takes `Authorization: Bearer `. Keys are `eu_live_…` or `eu_test_…`, and carry either `full_access` or the send-only `sending_access` permission.


    **Errors.** Non-2xx responses are always `{ "error": string, "code": string }`. Branch on `code`; the list is enumerated on the `Error` schema.


    **Conventions.** Request bodies use snake_case and reject unknown properties. Response bodies use camelCase, except the pagination cursor and a handful of endpoints noted inline. List endpoints are cursor-paginated, newest first. Every response carries `X-Request-Id`.'
  termsOfService: https://eusend.dev/legal/terms
  contact:
    name: eusend support
    email: support@eusend.dev
    url: https://eusend.dev/support
  license:
    name: Proprietary
    url: https://eusend.dev/legal/terms
servers:
- url: https://api.eusend.dev
  description: Production
security:
- bearerAuth: []
tags:
- name: Audiences
  description: Named contact lists a broadcast can be sent to.
paths:
  /audiences:
    post:
      operationId: createAudience
      summary: Create an audience
      description: An audience is a named contact list a broadcast can be sent to.
      tags:
      - Audiences
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateAudienceRequest'
      responses:
        '201':
          description: Created.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Audience'
        '400':
          description: The request body or query failed validation (`VALIDATION_ERROR`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '401':
          description: Missing, malformed, or revoked API key (`UNAUTHORIZED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '403':
          description: The key exists but may not reach this resource — a `sending_access` key outside the send paths, a test-mode key writing live state, or an account on hold (`FORBIDDEN`, `ACCOUNT_RESTRICTED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '429':
          description: Rate limit exceeded (`RATE_LIMITED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '500':
          description: Unexpected server error (`INTERNAL_ERROR`). Carries `request_id`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
    get:
      operationId: listAudiences
      summary: List audiences
      description: Newest first, each with its current contact count.
      tags:
      - Audiences
      responses:
        '200':
          description: The audiences.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ListAudiencesResponse'
        '401':
          description: Missing, malformed, or revoked API key (`UNAUTHORIZED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '403':
          description: The key exists but may not reach this resource — a `sending_access` key outside the send paths, a test-mode key writing live state, or an account on hold (`FORBIDDEN`, `ACCOUNT_RESTRICTED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '429':
          description: Rate limit exceeded (`RATE_LIMITED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '500':
          description: Unexpected server error (`INTERNAL_ERROR`). Carries `request_id`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
  /audiences/{id}:
    get:
      operationId: getAudience
      summary: Get an audience
      description: One audience with its current contact count.
      tags:
      - Audiences
      parameters:
      - name: id
        in: path
        required: true
        description: The audience id.
        schema:
          type: string
          format: uuid
      responses:
        '200':
          description: The audience.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/AudienceListItem'
        '401':
          description: Missing, malformed, or revoked API key (`UNAUTHORIZED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '403':
          description: The key exists but may not reach this resource — a `sending_access` key outside the send paths, a test-mode key writing live state, or an account on hold (`FORBIDDEN`, `ACCOUNT_RESTRICTED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '404':
          description: No such resource on this organization (`NOT_FOUND`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '429':
          description: Rate limit exceeded (`RATE_LIMITED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '500':
          description: Unexpected server error (`INTERNAL_ERROR`). Carries `request_id`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
    patch:
      operationId: updateAudience
      summary: Rename an audience
      description: Changes the audience name. Its contacts are untouched.
      tags:
      - Audiences
      parameters:
      - name: id
        in: path
        required: true
        description: The audience id.
        schema:
          type: string
          format: uuid
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateAudienceRequest'
      responses:
        '200':
          description: Updated.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Audience'
        '400':
          description: The request body or query failed validation (`VALIDATION_ERROR`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '401':
          description: Missing, malformed, or revoked API key (`UNAUTHORIZED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '403':
          description: The key exists but may not reach this resource — a `sending_access` key outside the send paths, a test-mode key writing live state, or an account on hold (`FORBIDDEN`, `ACCOUNT_RESTRICTED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '404':
          description: No such resource on this organization (`NOT_FOUND`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '429':
          description: Rate limit exceeded (`RATE_LIMITED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '500':
          description: Unexpected server error (`INTERNAL_ERROR`). Carries `request_id`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
    delete:
      operationId: deleteAudience
      summary: Delete an audience
      description: Deletes the audience and its contacts. Refused while a broadcast to it is scheduled or sending.
      tags:
      - Audiences
      parameters:
      - name: id
        in: path
        required: true
        description: The audience id.
        schema:
          type: string
          format: uuid
      responses:
        '200':
          description: Deleted.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EmptyResponse'
        '401':
          description: Missing, malformed, or revoked API key (`UNAUTHORIZED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '403':
          description: The key exists but may not reach this resource — a `sending_access` key outside the send paths, a test-mode key writing live state, or an account on hold (`FORBIDDEN`, `ACCOUNT_RESTRICTED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '404':
          description: No such resource on this organization (`NOT_FOUND`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '409':
          description: A scheduled or in-flight broadcast still needs this audience (`CONFLICT`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '429':
          description: Rate limit exceeded (`RATE_LIMITED`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '500':
          description: Unexpected server error (`INTERNAL_ERROR`). Carries `request_id`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
components:
  schemas:
    ListAudiencesResponse:
      type: object
      required:
      - data
      properties:
        data:
          type: array
          items:
            $ref: '#/components/schemas/AudienceListItem'
    Error:
      type: object
      description: Every non-2xx response from the API has this shape. `code` is stable and safe to branch on; `error` is a human sentence that may change.
      required:
      - error
      - code
      properties:
        error:
          type: string
          description: Human-readable explanation of the failure.
        code:
          type: string
          enum:
          - UNAUTHORIZED
          - FORBIDDEN
          - NOT_FOUND
          - VALIDATION_ERROR
          - RATE_LIMITED
          - MONTHLY_LIMIT_EXCEEDED
          - DAILY_LIMIT_EXCEEDED
          - PLAN_LIMIT_EXCEEDED
          - ALL_SUPPRESSED
          - RECIPIENT_DOMAIN_UNDELIVERABLE
          - DOMAIN_NOT_VERIFIED
          - SENDING_SUSPENDED
          - ACCOUNT_RESTRICTED
          - WORKSPACE_INACTIVE
          - SENDER_NOT_PERMITTED
          - SERVICE_PAUSED
          - LIST_SEND_HELD
          - BROADCAST_HELD
          - ATTACHMENT_STORAGE_ERROR
          - INTERNAL_ERROR
          - CONFLICT
          - BAD_REQUEST
          - PAYLOAD_TOO_LARGE
          description: Stable machine-readable error code.
        request_id:
          type: string
          description: Correlation id, returned on 500s and echoed in the `X-Request-Id` header on every response. Quote it in support requests.
    EmptyResponse:
      type: object
      description: An empty object. The resource is gone.
      additionalProperties: false
    Audience:
      type: object
      required:
      - id
      - name
      - organizationId
      - createdAt
      properties:
        id:
          type: string
          format: uuid
        name:
          type: string
        organizationId:
          type: string
          format: uuid
        createdAt:
          type: string
          format: date-time
        updatedAt:
          type:
          - string
          - 'null'
          format: date-time
    CreateAudienceRequest:
      type: object
      required:
      - name
      additionalProperties: false
      properties:
        name:
          type: string
          minLength: 1
          maxLength: 100
    AudienceListItem:
      type: object
      required:
      - id
      - name
      - createdAt
      - contactCount
      properties:
        id:
          type: string
          format: uuid
        name:
          type: string
        createdAt:
          type: string
          format: date-time
        contactCount:
          type: integer
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: 'An eusend API key, sent as `Authorization: Bearer eu_live_…`. Create one in the dashboard under API keys.'
externalDocs:
  description: eusend documentation
  url: https://eusend.dev/docs