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OpenAPI Specification
openapi: 3.2.0
info:
title: Plunk Segments API
description: Open-source email platform API for transactional emails, campaigns, and marketing automation
version: 1.0.0
contact:
name: Plunk Support
url: https://www.useplunk.com
servers:
- url: https://next-api.useplunk.com
description: Production server
security:
- ApiKeyAuth: []
tags:
- name: Segments
description: Audience segmentation
paths:
/segments:
get:
tags:
- Segments
summary: List segments
description: Get all audience segments for the project, newest first. This endpoint is not paginated — it returns a bare array of every segment.
operationId: listSegments
responses:
'200':
description: List of segments
content:
application/json:
schema:
type: array
items:
$ref: '#/components/schemas/Segment'
'401':
$ref: '#/components/responses/Unauthorized'
post:
tags:
- Segments
summary: Create segment
description: 'Create a new audience segment.
**`DYNAMIC` segments** (the default) are defined by a `condition` — a boolean tree that is re-evaluated against your contacts, so membership changes on its own as contact data changes. `condition` is required for these.
**`STATIC` segments** hold a manually managed member list; `condition` is ignored. Add members with `POST /segments/{id}/members`.'
operationId: createSegment
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- name
properties:
name:
type: string
maxLength: 100
description:
type: string
maxLength: 500
type:
type: string
enum:
- DYNAMIC
- STATIC
default: DYNAMIC
description: Defaults to `DYNAMIC` when omitted.
condition:
allOf:
- $ref: '#/components/schemas/FilterCondition'
description: Required for `DYNAMIC` segments; ignored for `STATIC` ones.
trackMembership:
type: boolean
default: false
description: Emit `segment.<slug>.entry` / `segment.<slug>.exit` events as contacts join and leave. These can be used as workflow triggers.
examples:
simple:
summary: Premium users
value:
name: Premium Users
condition:
logic: AND
groups:
- filters:
- field: data.plan
operator: equals
value: premium
trackMembership: true
orLogic:
summary: Either of two groups (OR)
description: Filters inside a group are ANDed; `logic` combines the groups. This matches premium users OR anyone who signed up in the last 7 days.
value:
name: Premium or new
description: Targets for the onboarding push
condition:
logic: OR
groups:
- filters:
- field: data.plan
operator: equals
value: premium
- field: subscribed
operator: equals
value: true
- filters:
- field: createdAt
operator: within
value: 7
unit: days
eventBased:
summary: Based on a tracked event
description: Contacts who triggered `purchase` in the last 30 days.
value:
name: Recent purchasers
condition:
logic: AND
groups:
- filters:
- field: purchase
operator: triggeredWithin
value: 30
unit: days
static:
summary: Static segment
value:
name: Beta testers
type: STATIC
responses:
'201':
description: Segment created
content:
application/json:
schema:
$ref: '#/components/schemas/Segment'
'400':
description: '`name` is missing, or `condition` is missing on a `DYNAMIC` segment.'
content:
application/json:
schema:
$ref: '#/components/schemas/LegacyError'
example:
error: Condition is required and must be an object for DYNAMIC segments
'401':
$ref: '#/components/responses/Unauthorized'
components:
schemas:
FilterGroup:
type: object
required:
- filters
properties:
filters:
type: array
items:
$ref: '#/components/schemas/Filter'
description: Filters within a group are combined with AND.
conditions:
$ref: '#/components/schemas/FilterCondition'
description: Optional nested condition, allowing arbitrarily deep AND/OR trees.
FilterCondition:
type: object
required:
- logic
- groups
description: A boolean tree over contact filters. `logic` combines the `groups`; the filters inside each group are always ANDed together.
properties:
logic:
type: string
enum:
- AND
- OR
groups:
type: array
minItems: 1
items:
$ref: '#/components/schemas/FilterGroup'
FieldError:
type: object
properties:
field:
type: string
description: Dot-path of the offending field, e.g. `attachments.0.filename`.
message:
type: string
code:
type: string
description: Validation issue code, e.g. `invalid_type`, `too_big`, `reserved_event`.
received:
description: The value that was received, when available.
Filter:
type: object
required:
- field
- operator
properties:
field:
type: string
description: Contact field to test. Custom fields are addressed via the `data.` prefix (e.g. `data.plan`); standard fields are `email`, `subscribed`, `createdAt`. Event operators take an event name instead.
operator:
type: string
enum:
- equals
- notEquals
- contains
- notContains
- greaterThan
- lessThan
- greaterThanOrEqual
- lessThanOrEqual
- exists
- notExists
- within
- olderThan
- triggered
- triggeredWithin
- triggeredOlderThan
- notTriggered
- notTriggeredWithin
- memberOfSegment
- notMemberOfSegment
value:
description: Comparison value. Omitted for `exists` / `notExists` / `triggered` / `notTriggered`. For time-window operators this is the number of `unit`s.
unit:
type: string
enum:
- days
- hours
- minutes
description: Time unit for window operators (`within`, `olderThan`, `triggeredWithin`, `triggeredOlderThan`, `notTriggeredWithin`).
Segment:
type: object
properties:
id:
type: string
name:
type: string
description:
type: string
nullable: true
type:
type: string
enum:
- DYNAMIC
- STATIC
description: '`DYNAMIC` segments are evaluated from `condition`. `STATIC` segments hold a manually managed member list.'
condition:
allOf:
- $ref: '#/components/schemas/FilterCondition'
nullable: true
description: Filter condition for `DYNAMIC` segments. Null for `STATIC` segments.
trackMembership:
type: boolean
description: When true, contacts entering or leaving the segment emit `segment.<slug>.entry` / `segment.<slug>.exit` events.
memberCount:
type: integer
description: Cached member count, refreshed by a background job rather than computed per request.
projectId:
type: string
createdAt:
type: string
format: date-time
updatedAt:
type: string
format: date-time
LegacyError:
type: object
description: Flat error shape returned by the hand-validated create/update endpoints (`POST /contacts`, `POST /templates`, `POST /segments`) for missing required fields. Unlike the rest of the API these return `400` with a bare `error` string rather than the standard envelope. Errors raised deeper in those same endpoints (404, 409, domain verification) still use the standard `Error` envelope.
properties:
error:
type: string
Error:
type: object
properties:
success:
type: boolean
enum:
- false
error:
type: object
properties:
code:
type: string
description: Machine-readable error code, e.g. `VALIDATION_ERROR`, `INVALID_API_KEY`, `IDEMPOTENCY_KEY_REUSED`.
message:
type: string
statusCode:
type: integer
requestId:
type: string
description: Correlation ID for this request. Include it when contacting support.
errors:
type: array
items:
$ref: '#/components/schemas/FieldError'
description: Field-level detail, present on validation failures.
details:
type: object
additionalProperties: true
description: Additional error context.
suggestion:
type: string
description: Hint for fixing the request.
timestamp:
type: string
format: date-time
responses:
Unauthorized:
description: Missing or invalid API key.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: INVALID_API_KEY
message: Invalid secret API key. This endpoint requires a secret key (sk_*), not a public key.
statusCode: 401
requestId: 8f14e45f-ceea-467a-9575-1f0f38e0b1c2
timestamp: '2025-01-15T10:30:00.000Z'
securitySchemes:
ApiKeyAuth:
type: http
scheme: bearer
bearerFormat: API Key
description: 'API Key authentication. The project is automatically derived from the key.
**`/v1/track` requires a public key (`pk_*`)** — it is the one endpoint intended for client-side use, and a secret key is rejected there with `401`.
**Every other endpoint requires a secret key (`sk_*`)** and rejects public keys with `401`.
So the two key types are not interchangeable in either direction: pick the key that matches the endpoint you are calling.'
x-ext-urls: {}