Customer.io website screenshot

Customer.io

Customer.io is a customer messaging and marketing automation platform. Its APIs let teams pipe behavioral data in, manage people and their attributes, trigger campaigns and broadcasts, send transactional email, push, SMS, and in-app messages, and stream delivery activity back out via reporting webhooks. The surface spans the Track API (basic site-id + api-key auth), the App / Transactional API (Bearer), and the Pipelines / Data Pipelines CDP API.

Customer.io publishes 13 APIs on the APIs.io network, including Broadcasts API, Campaigns API, Collections API, and 10 more. Tagged areas include Customer Messaging, Marketing Automation, Email, CDP, and Transactional.

Customer.io’s developer surface includes authentication, documentation, and 10 more developer resources.

🌐 Visit website 📡 Source on GitHub
39.8/100 thin ▬ flat Agent 31/100 agent aware Full breakdown ↓
scored 2026-07-28 · rubric v0.6
AccessPaidSelf serve
14 APIs
Customer MessagingMarketing AutomationEmailCDPTransactional

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-28 · rubric v0.6
Composite quality — 39.8/100 · thin
Contract Quality 14.3 / 25
Developer Ergonomics 3.9 / 20
Commercial Clarity 9.5 / 20
Operational Transparency 4.8 / 13
Governance 0.0 / 12
Discoverability 7.4 / 10
Agent readiness — 31/100 · agent aware
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 0 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/customerio: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 14

Individual APIs this provider publishes, each with its own machine-readable definition.

Customer.io Reporting Webhooks

Outbound reporting webhooks that POST real-time message activity events (email/sms/push/in-app delivered, opened, clicked, bounced, converted, unsubscribed, and more) as JSON to...

Customer.io Broadcasts API

App API - trigger API-driven broadcasts.

Customer.io Campaigns API

App API - read campaigns, their metrics, and actions.

Customer.io Collections API

App API - manage reusable data collections.

Customer.io Customers API

App API - look up people, their attributes, segments, and messages.

Customer.io Devices API

Track API - register and remove customer device tokens.

Customer.io Events API

Track API - send customer or anonymous behavioral events.

Customer.io Exports API

App API - export customers and deliveries.

Customer.io Messages API

App API - read sent messages and their metadata.

Customer.io People API

Track API - add, update, suppress, or delete people (customers).

Customer.io Pipelines API

Pipelines / CDP API - identify, track, page, screen, group, alias, batch.

Customer.io Segments API

Manual segment membership management.

Customer.io Track v2 API

Track API v2 entity and batch endpoints.

Customer.io Transactional API

App API - send transactional email, push, SMS, and in-app messages.

Scroll for all 14

Open Collections 1

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Customer.io API

OPEN COLLECTION

Pricing Plans 1

Published pricing tiers and plan structures.

Customerio Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Customerio Rate Limits

6 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Customerio Finops

FINOPS

Security Posture 4

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Customerio Authentication

http · 2 schemes

SECURITY

Customerio Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Customerio Vulnerability Disclosure

disclosure policy published

SECURITY

Customerio Trust Center

SOC 2, ISO 27001, HIPAA, GDPR

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Customerio Agentic Access

35 operations · 25 acting

35 operations · 25 acting

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Documentation
Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess
AgenticAccess

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization
GitHubOrganization

Access & Security 4

Authentication, authorization, and security posture

TrustCenter
TrustCenter
 VulnerabilityDisclosure
VulnerabilityDisclosure
 DomainSecurity
DomainSecurity
 Authentication
Authentication

Operate 1

Status, limits, changes, and where to get help

RateLimits
RateLimits

Commercial 2

Pricing, plans, and the legal terms of use

Plans
Plans
 FinOps
FinOps

Company 2

The organization behind the API

LinkedIn
LinkedIn
 Website
Website

Source (apis.yml)

apis.yml Raw ↑ 
aid: customerio
url: https://raw.githubusercontent.com/api-evangelist/customerio/refs/heads/main/apis.yml
name: Customer.io
kind: company
description: Customer.io is a customer messaging and marketing automation platform. Its APIs let teams pipe behavioral data
  in, manage people and their attributes, trigger campaigns and broadcasts, send transactional email, push, SMS, and in-app
  messages, and stream delivery activity back out via reporting webhooks. The surface spans the Track API (basic site-id +
  api-key auth), the App / Transactional API (Bearer), and the Pipelines / Data Pipelines CDP API.
accessModel:
  pricing: paid
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Paid · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/customerio.png
tags:
- Customer Messaging
- Marketing Automation
- Email
- CDP
- Transactional
created: '2026-06-20'
modified: '2026-06-20'
specificationVersion: '0.19'
apis:
- aid: customerio:reporting-webhooks
  name: Customer.io Reporting Webhooks
  tags:
  - Webhooks
  - Events
  - Reporting
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://docs.customer.io/integrations/api/webhooks/
  baseURL: https://docs.customer.io/integrations/api/webhooks/
  properties:
  - url: https://docs.customer.io/integrations/api/webhooks/
    type: Documentation
  - url: https://docs.customer.io/integrations/data-out/connections/webhooks/
    type: APIReference
  description: Outbound reporting webhooks that POST real-time message activity events (email/sms/push/in-app delivered, opened,
    clicked, bounced, converted, unsubscribed, and more) as JSON to a customer-supplied HTTPS endpoint.
- aid: customerio:customerio-broadcasts-api
  name: Customer.io Broadcasts API
  description: App API - trigger API-driven broadcasts.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Broadcasts
  properties:
  - type: OpenAPI
    url: openapi/customerio-broadcasts-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-campaigns-api
  name: Customer.io Campaigns API
  description: App API - read campaigns, their metrics, and actions.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Campaigns
  properties:
  - type: OpenAPI
    url: openapi/customerio-campaigns-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-collections-api
  name: Customer.io Collections API
  description: App API - manage reusable data collections.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Collections
  properties:
  - type: OpenAPI
    url: openapi/customerio-collections-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-customers-api
  name: Customer.io Customers API
  description: App API - look up people, their attributes, segments, and messages.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Customers
  properties:
  - type: OpenAPI
    url: openapi/customerio-customers-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-devices-api
  name: Customer.io Devices API
  description: Track API - register and remove customer device tokens.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Devices
  properties:
  - type: OpenAPI
    url: openapi/customerio-devices-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-events-api
  name: Customer.io Events API
  description: Track API - send customer or anonymous behavioral events.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Events
  properties:
  - type: OpenAPI
    url: openapi/customerio-events-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-exports-api
  name: Customer.io Exports API
  description: App API - export customers and deliveries.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Exports
  properties:
  - type: OpenAPI
    url: openapi/customerio-exports-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-messages-api
  name: Customer.io Messages API
  description: App API - read sent messages and their metadata.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Messages
  properties:
  - type: OpenAPI
    url: openapi/customerio-messages-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-people-api
  name: Customer.io People API
  description: Track API - add, update, suppress, or delete people (customers).
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - People
  properties:
  - type: OpenAPI
    url: openapi/customerio-people-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-pipelines-api
  name: Customer.io Pipelines API
  description: Pipelines / CDP API - identify, track, page, screen, group, alias, batch.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Pipelines
  properties:
  - type: OpenAPI
    url: openapi/customerio-pipelines-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-segments-api
  name: Customer.io Segments API
  description: Manual segment membership management.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Segments
  properties:
  - type: OpenAPI
    url: openapi/customerio-segments-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-track-v2-api
  name: Customer.io Track v2 API
  description: Track API v2 entity and batch endpoints.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Track v2
  properties:
  - type: OpenAPI
    url: openapi/customerio-track-v2-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
- aid: customerio:customerio-transactional-api
  name: Customer.io Transactional API
  description: App API - send transactional email, push, SMS, and in-app messages.
  humanURL: https://docs.customer.io/integrations/api/track/
  baseURL: https://track.customer.io/api/v1
  tags:
  - Transactional
  properties:
  - type: OpenAPI
    url: openapi/customerio-transactional-api-openapi.yml
  - type: Documentation
    url: https://docs.customer.io/integrations/api/track/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/track/
  - type: PostmanCollection
    url: collections/customerio.postman_collection.json
  - type: Documentation
    url: https://docs.customer.io/integrations/api/app/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/app/
  - type: Documentation
    url: https://docs.customer.io/integrations/api/cdp/
  - type: APIReference
    url: https://docs.customer.io/integrations/api/cdp/
common:
- type: AgenticAccess
  url: agentic-access/customerio-agentic-access.yml
- type: TrustCenter
  url: security/customerio-trust-center.yml
- type: VulnerabilityDisclosure
  url: security/customerio-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/customerio-domain-security.yml
- type: Authentication
  url: authentication/customerio-authentication.yml
- type: GitHubOrganization
  url: https://github.com/customerio
- type: LinkedIn
  url: https://www.linkedin.com/company/customer-io
- type: Website
  url: https://customer.io
- type: Documentation
  url: https://docs.customer.io
- type: Plans
  url: plans/customerio-plans-pricing.yml
- type: RateLimits
  url: rate-limits/customerio-rate-limits.yml
- type: FinOps
  url: finops/customerio-finops.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com