Customer.io

Customer.io Track Customers API

Add, modify, suppress, or unsuppress people (referred to as "customers" in our APIs). You can also use these endpoints to set attributes on people.

GitHub OpenAPI
Business capability
Customer Data Management BC-420.10

Operations 8

Each operation below carries the questions people ask an LLM about it and the instructions they give an agent to run it. Generated by API Evangelist overlay

PUT /api/v1/customers/{identifier} Add or update a person · Add or update a customer #
Ask an LLM
“How do I create or update a person's profile with the Track API?”
“Can I set a person's email and created date when adding them?”
Tell an agent
Add or update person {identifier} with email {email}.
Update person {identifier} and mark them unsubscribed: {unsubscribed}.
DELETE /api/v1/customers/{identifier} Delete a person · Delete a customer #
Ask an LLM
“How do I delete a person and all their data?”
“Could a later update call recreate a person I deleted?”
Tell an agent destructive · confirm first
Delete person {identifier}.
Remove {identifier} and all their information.
PUT /api/v1/customers/{identifier}/devices Add or update a person's device · Add or update a customer device #
Ask an LLM
“How do I register an iOS or Android push token for a person?”
“Can a person have more than one device?”
Tell an agent
Add device {device} to person {identifier}.
Register push token {device} for {identifier}.
DELETE /api/v1/customers/{identifier}/devices/{device_id} Remove a device from a person · Delete a customer device #
Ask an LLM
“How do I remove an old device from a person's profile?”
“Why does a deleted device keep reappearing?”
Tell an agent destructive · confirm first
Delete device {device_id} from person {identifier}.
Remove push device {device_id} for {identifier}.
POST /api/v1/customers/{identifier}/suppress Suppress a person permanently · Suppress a customer profile #
Ask an LLM
“How do I delete a person and block them from being re-added?”
“What happens to API calls referencing a suppressed identifier?”
Tell an agent destructive · confirm first
Suppress person {identifier}.
Delete and block {identifier} from coming back.
POST /api/v1/customers/{identifier}/unsuppress Unsuppress a person · Unsuppress a customer profile #
Ask an LLM
“How do I allow a suppressed person to be added again?”
“Does unsuppressing restore the person's old data?”
Tell an agent
Unsuppress person {identifier}.
Allow {identifier} to be re-added.
POST /unsubscribe/{delivery_id} Unsubscribe a person from a delivery link · Custom unsubscribe handling #
Ask an LLM
“How do I handle unsubscribes from my own custom unsubscribe page?”
“Can I set someone's global unsubscribe status from a delivery ID?”
Tell an agent
Unsubscribe the recipient of delivery {delivery_id}.
Set unsubscribe to {unsubscribe} for the person who got delivery {delivery_id}.
POST /api/v1/merge_customers Merge two duplicate people · Merge duplicate people #
Ask an LLM
“How do I merge two duplicate profiles into one?”
“Which profile survives when I merge duplicates?”
Tell an agent destructive · confirm first
Merge {secondary} into {primary}.
Combine duplicate profile {secondary} with primary {primary}.

Documentation

📖
Documentation
https://docs.customer.io/integrations/api/app/
📖
Documentation
https://docs.customer.io/integrations/data-in/connections/http-api/

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/customer-io/refs/heads/main/openapi/customer-io-track-customers-api-openapi.yml

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OpenAPI Specification

customer-io-track-customers-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  version: 1.0.0
  title: Customer.io Track Track Customers API
  description: '# Overview


    Our Track API provides ways to send real-time customer data to your Customer.io workspace including customer identification and event tracking.'
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.
tags:


# --- truncated at 32 KB (40 KB total) ---
# Full source: https://raw.githubusercontent.com/api-evangelist/customer-io/refs/heads/main/openapi/customer-io-track-customers-api-openapi.yml