Update descriptions for attributes and events in your workspace. This helps improve AI-generated content and segments.
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openapi: 3.2.0
info:
version: 1.0.0
title: Customer.io Journeys API Reference Data Index API
description: Customer.io provides REST APIs to send real-time customer data, retrieve data from your account, and trigger messages.
servers:
- url: https://track.customer.io
description: The base URL for the Track API. Track endpoints use basic authentication with your Site ID as the user name and your secret key as the password.
- url: https://track-eu.customer.io
description: The base URL for the Track API (EU region). Track endpoints use basic authentication with your Site ID as the user name and your secret key as the password.
- url: https://api.customer.io
description: The base URL for broadcasts, transactional messages, and data-retrieval APIs. These endpoints use bearer authorization, and require a [token that you generate in the UI](https://fly.customer.io/settings/api_credentials?keyType=app).
- url: https://api-eu.customer.io
description: The base URL for broadcasts, transactional messages, and data-retrieval APIs (EU region). These endpoints use bearer authorization, and require a [token that you generate in the UI](https://fly.customer.io/settings/api_credentials?keyType=app).
tags:
- name: Data Index
description: Update descriptions for attributes and events in your workspace. This helps improve AI-generated content and segments.
paths:
/v1/data_index/attributes:
servers:
- url: https://api.customer.io
description: The base URL for broadcasts, transactional messages, and data-retrieval APIs. These endpoints use bearer authorization, and require a [token that you generate in the UI](https://fly.customer.io/settings/api_credentials?keyType=app).
- url: https://api-eu.customer.io
description: The base URL for broadcasts, transactional messages, and data-retrieval APIs (EU region). These endpoints use bearer authorization, and require a [token that you generate in the UI](https://fly.customer.io/settings/api_credentials?keyType=app).
post:
summary: Add or update attributes
operationId: updateAttributeMetadata
security:
- Bearer-Auth: []
description: 'Attributes are customer data like their name and email. Use this endpoint to add new attributes or update existing attributes in your workspace. To add attributes to customers, use our Pipelines or Track APIs. **NOTE:** If you add new attributes, they will not appear in your Data Index until you''ve added it to a customer''s profile.
Add descriptions for attributes so our AI tools can better understand your data. For instance, this influences how our segment builder generates conditions with AI.
If you''re on a Premium plan, you can also specify whether an attribute is sensitive or not. Then Admins and Workspace Admins can decide which teammates to hide sensitive data from.'
tags:
- Data Index
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- attributes
properties:
attributes:
type: array
description: Array of attribute updates
minItems: 1
maxItems: 100
items:
type: object
required:
- name
properties:
name:
type: string
description: The name of the attribute to update
example: last_active
description:
type: string
maxLength: 255
description: The purpose of the attribute. This helps our AI tools understand your data.
example: The last time the user clicked something on our app after logging in.
privacy_level:
type: integer
enum:
- 0
- 1
description: 'Available on Premium plans. This indicates whether an attribute is sensitive or not.
0 means NOT sensitive.
1 means sensitive.
'
example: 0
responses:
'204':
description: Attributes updated successfully
'400':
description: Invalid request format
content:
application/json:
schema:
type: object
properties:
errors:
type: array
items:
type: object
properties:
detail:
type: string
description: The reason for failure.
enum:
- Invalid request format
status:
type: string
description: The response code.
enum:
- 400
'422':
description: Validation error
content:
application/json:
schema:
type: object
properties:
errors:
type: array
items:
type: object
properties:
detail:
type: string
description: The reason for the response.
enum:
- Empty attributes array
- Too many attributes
- Privacy level feature not enabled
status:
type: string
description: The response code.
enum:
- 422
source:
type: object
properties:
pointer:
type: string
description: The path to the attribute that caused the error. 0 is the first attribute, 1 is the second, and so on.
examples:
empty_attributes:
summary: Empty attributes array
value:
errors:
- detail: At least one attribute is required
source:
pointer: /data/attributes/attributes
status: '422'
too_many_attributes:
summary: Too many attributes
value:
errors:
- detail: Can not update more than 100 attributes at once
source:
pointer: /data/attributes/attributes
status: '422'
privacy_level_not_enabled:
summary: Privacy level feature not enabled
value:
errors:
- detail: Privacy level updates are not available. Please contact support to enable this feature.
source:
pointer: /data/attributes/attributes[0].privacy_level
status: '422'
'500':
description: Internal server error
/v1/data_index/events:
servers:
- url: https://api.customer.io
description: The base URL for broadcasts, transactional messages, and data-retrieval APIs. These endpoints use bearer authorization, and require a [token that you generate in the UI](https://fly.customer.io/settings/api_credentials?keyType=app).
- url: https://api-eu.customer.io
description: The base URL for broadcasts, transactional messages, and data-retrieval APIs (EU region). These endpoints use bearer authorization, and require a [token that you generate in the UI](https://fly.customer.io/settings/api_credentials?keyType=app).
post:
summary: Add or update events
operationId: updateEventMetadata
security:
- Bearer-Auth: []
description: 'Events are actions your customers have performed. Use this endpoint to add new events or update existing events in your workspace. To associate events with customers, use our Pipelines or Track APIs. **NOTE:** If you add new events, they will not appear in your Data Index until you''ve associated it with a customer.
Add descriptions for events so our AI tools can better understand your data. For instance, this influences how our segment builder generates conditions with AI.'
tags:
- Data Index
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- events
properties:
events:
type: array
description: Array of event updates
minItems: 1
maxItems: 100
items:
type: object
required:
- name
properties:
name:
type: string
description: The name of the event
example: purchase_completed
description:
type: string
maxLength: 255
description: The meaning of the event
example: User successfully completed a purchase
responses:
'204':
description: Events updated successfully
'400':
description: Invalid request format
content:
application/json:
schema:
type: object
properties:
errors:
type: array
items:
type: object
properties:
detail:
type: string
description: The reason for the response.
enum:
- Invalid request format
status:
type: string
description: The response code.
enum:
- 400
'422':
description: Validation error
content:
application/json:
schema:
type: object
properties:
errors:
type: array
items:
type: object
properties:
detail:
type: string
enum:
- Empty events array
- Too many events
description: The reason for the response.
status:
type: string
enum:
- 422
source:
type: object
properties:
pointer:
type: string
description: The path to the event that caused the error.
examples:
empty_events:
summary: Empty events array
value:
errors:
- detail: At least one event is required
source:
pointer: /data/attributes/events
status: '422'
too_many_events:
summary: Too many events
value:
errors:
- detail: Can not update more than 100 events at once
source:
pointer: /data/attributes/events
status: '422'
'500':
description: Internal server error
components:
securitySchemes:
Tracking-API-Key:
type: http
scheme: basic
description: 'The Track API uses a basic authentication scheme. Your credentials are your **Site ID** and your **API key**, **Base-64 encoded** in the format `site_id:api_key`.
You can find your Site ID and API key on the [Track API Keys page](https://fly.customer.io/settings/api_credentials).
'
Bearer-Auth:
type: http
scheme: bearer
description: 'The App API uses a bearer authentication scheme.
You can generate a bearer token, known as an **App API Key**, with a defined scope in [your account settings](https://fly.customer.io/settings/api_credentials?keyType=app). [Learn more about bearer authorization in Customer.io](/accounts/settings/managing-credentials).
'
ServiceAccount-Auth:
x-scalar-ignore: true
type: http
scheme: bearer
bearerFormat: sa_live_
description: 'Transactional send endpoints (`/v1/send/email`, `/v1/send/push`, `/v1/send/sms`, `/v1/send/whatsapp`, `/v1/send/in_app`, `/v1/send/inbox_message`) also accept a service-account bearer token, prefixed with `sa_live_`. Service-account tokens work across workspaces, so you must pass the target workspace as the `X-Workspace-Id` header on each request.
Service-account tokens are intended for testing and one-off sends—for example, using the Customer.io CLI with an AI agent like Claude to verify that a transactional message renders correctly before wiring it into your production backend. **For the production integration that triggers the message from your application, use an App API Key instead**: it''s workspace-scoped, easier to rotate, and has a smaller blast radius.
Service-account tokens are server-side credentials. Treat them like any API key—keep them in environment variables or a secret manager, and never embed them in client-side code, mobile apps, or other untrusted contexts.
'
bearerAuth:
type: http
scheme: bearer
description: API key passed as a Bearer token.
x-tagGroups:
- name: Track API v2
tags:
- track_v2
- Object Schemas
- Person Schemas
- Deliveries
- name: Track API
tags:
- trackOverview
- trackJsOrBackend
- trackLimit
- trackRegion
- Track Customers
- Track Events
- Forms
- Track Segments
- Track v1 Overview
- name: App API
tags:
- appOverview
- appLimit
- appAuth
- Activities
- Automations
- Broadcasts
- Collections
- Customers
- Data Index
- ESP Suppression
- Exports
- Imports
- Info
- Live Notifications
- Messages
- Newsletters
- Opt-outs
- Reporting Webhooks
- Segments
- Sender Identities
- Snippets
- Subscription Center
- Transactional
- Workspaces
- Send Messages
- Objects
- Newsletter Variants
- Newsletter Metrics
- Assets
- name: Design Studio API
tags:
- Folders
- Components
- Emails
- Email link and publish
- Email testing
- SMS
- SMS link and publish
x-provenance:
method: harvested
publisher: Customer.io
source: https://docs.customer.io/openapi.yaml
note: split by refine-openapis from the provider's own published document, verified by fetch (openapi/_original/*.fetch.json);
stamped by stamp-openapi-provenance.py (roadmap#793)