Customer.io

Customer.io Messages API

Retrieve information about individual messages sent to customers.

GitHub OpenAPI

Operations 3

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/messages List message deliveries in the workspace · List messages #
Ask an LLM
“How do I see all the messages my workspace sent yesterday?”
“Can I filter workspace deliveries by campaign, newsletter or action?”
Tell an agent
List workspace deliveries with metric {metric}.
Show deliveries for campaign {campaign_id} across the workspace.
GET /v1/messages/{message_id} Get a delivery and its metrics · Get a message #
Ask an LLM
“Was a specific message delivered and opened?”
“How do I see the metrics for one delivery?”
Tell an agent
Get delivery {message_id}.
Show metrics for message {message_id}.
GET /v1/messages/{message_id}/archived_message Get the archived copy of a message · Get an archived message #
Ask an LLM
“How do I see exactly what content a person received in a message?”
“Is there a daily limit on fetching archived messages?”
Tell an agent
Get the archived copy of message {message_id}.
Show me the body that was sent in delivery {message_id}.

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-messages-api-openapi.yml

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OpenAPI Specification

customer-io-messages-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  version: 1.0.0
  title: Customer.io App Messages 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-messages-api-openapi.yml