Customer.io

Customer.io Customers API

Look up customer profiles, search for customers, and retrieve customer attributes and activity data.

GitHub OpenAPI
Business capability
Customer Data Management BC-420.10

Operations 9

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

GET /v1/customers Find people by email address · Get customers by email #
Ask an LLM
“How do I find a person's profile when I only know their email?”
“Can more than one person match the same email address?”
Tell an agent
Find people with email {email}.
Look up the profile for {email}.
POST /v1/customers Search people by segment or attribute · Search for customers #
Ask an LLM
“How do I find everyone in a segment whose plan attribute is premium?”
“Can I page through people matching an attribute filter?”
Tell an agent
Search people matching filter {filter}.
Find up to {limit} people who match {filter}.
GET /v1/customers/{customer_id}/attributes Get a person's attributes · Lookup a customer's attributes #
Ask an LLM
“What attributes are stored on a person's profile?”
“Can I look up a person's attributes by email instead of ID?”
Tell an agent
Show the attributes for person {customer_id}.
Get profile attributes for {customer_id} using {id_type} as the identifier.
GET /v1/customers/{customer_id}/relationships List objects a person is related to · Lookup a customer's relationships #
Ask an LLM
“Which companies or accounts is a person linked to?”
“How do I page through a person's object relationships?”
Tell an agent
List the objects person {customer_id} is related to.
Show the accounts linked to {customer_id}.
POST /v1/customers/attributes Get attributes and devices for many people · List customers, attributes, and devices #
Ask an LLM
“How do I fetch attributes and devices for a batch of people at once?”
“What's the maximum number of people I can look up in one request?”
Tell an agent
Get attributes and devices for people {ids}.
Look up these customer IDs in bulk: {ids}.
GET /v1/customers/{customer_id}/segments List a person's segments · Lookup a customer's segments #
Ask an LLM
“Which segments is a given person in?”
“Why is this person receiving a campaign, which segments do they match?”
Tell an agent
List the segments person {customer_id} belongs to.
Show segment memberships for {customer_id}.
GET /v1/customers/{customer_id}/messages List messages sent to a person · Lookup messages sent to a customer #
Ask an LLM
“What messages has a specific person received from us?”
“Can I see deliveries to one person within a date range?”
Tell an agent
List messages sent to person {customer_id}.
Show deliveries to {customer_id} since {start_ts}.
GET /v1/customers/{customer_id}/activities List a person's activity history · Lookup a customer's activities #
Ask an LLM
“What has a person done recently, like attribute changes and events?”
“Can I filter one person's activity log to a specific event name?”
Tell an agent
Show the activity history for person {customer_id}.
List {customer_id}'s activities of type {type}.
GET /v1/customers/{customer_id}/subscription_preferences Get a person's subscription preferences · Lookup a customer's subscription preferences #
Ask an LLM
“Which subscription topics has a person opted into?”
“Can I get a person's subscription preferences in their language?”
Tell an agent
Show subscription preferences for person {customer_id}.
Get {customer_id}'s topic preferences in {language}.

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-customers-api-openapi.yml

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OpenAPI Specification

customer-io-customers-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  version: 1.0.0
  title: Customer.io App Customers API
  description: Our App API provides ways to trigger messages and retrieve information about people, campaigns, broadcasts, and more.
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).
tags:


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# Full source: https://raw.githubusercontent.com/api-evangelist/customer-io/refs/heads/main/openapi/customer-io-customers-api-openapi.yml