Overview

The CMR Integration API is a REST API for building fully white-labeled cold email infrastructure.

How It Works

You are a partner. Your customers are users. Every resource in CMR — a domain, a mailbox, a subscription — belongs to a user that belongs to your partner account.

Your customers never interact with CMR directly; they only interact with the platform you build on top of it.

Partner (your cmr-x-api-key)
└── Users (your customers)
    ├── Domains
    │   └── DNS Records
    ├── Mailboxes
    │   ├── Subscriptions
    │   └── Warmup
    └── Exports

Every API request operates at either the partner level (your account) or the user level (a specific customer). User-level requests require both your API key and a userId query parameter. See Authentication for the full breakdown.

Base URL

All endpoints are available under:

https://customers.coldmailreseller.com/api/v1/integration

Request Format

All write operations accept application/json. Pass your API key in every request header:

Response Format

Every response — success or error — uses the same envelope:

{
  "status": 200,
  "message": "User created",
  "data": {
    "id": "usr_abc123"
  }
}

On error, data is null and message describes what went wrong:

{
  "status": 404,
  "message": "The requested user does not exist.",
  "data": null
}

The status field in the body always matches the HTTP response status code.

Async Operations

Some operations — domain registration, mailbox provisioning, renewals — are processed in the background and return an actionId immediately. The final result is delivered via webhook.

Submit the request

Call the endpoint (e.g. POST /orders/json). You receive an actionId in the response — this confirms the operation was accepted, not that it completed.

{
  "status": 200,
  "data": { "actionId": "ACT_7a078272-0fa7-4db4-a85b-c78697dacea1" },
  "actionId": "ACT_7a078272-0fa7-4db4-a85b-c78697dacea1"
}

CMR processes in the background

CMR registers the domain, provisions mailboxes, or executes the renewal.

Receive the webhook

CMR POSTs the result to your configured webhook URL. Match it back to your original request using actionId.

{
  "event": "domain.order.success",
  "data": {
    "actionId": "ACT_7a078272-0fa7-4db4-a85b-c78697dacea1",
    "domains": [{ "domain": "mycoldoutreach.com", "status": "ACTIVE" }]
  }
}

WARNING

Never retry an async operation while waiting for its webhook. Duplicate submissions result in duplicate domain registrations and charges.

Environments

Production

All endpoints available. Real domain registrations, real charges, real webhooks. Use for live customer operations.

Base path: /api/v1/integration/

Sandbox

Sandbox endpoints only (/sandbox/*). $0 charges, test domains, webhooks fire just like production. Use scenario headers to control outcomes: success, full_failure, partial_failure.

Base path: /api/v1/sandbox/

Next Steps

Authentication

Partner-level vs user-level auth, API keys, and exact error messages.

Quick Start

Provision your first domain and mailbox end-to-end in under 5 minutes.

Errors

HTTP status codes, common error messages, and retry strategy.

How It Works#

Base URL#

Request Format#

Response Format#

Async Operations#

Environments#

Next Steps#

How It Works

Base URL

Request Format

Response Format

Async Operations

Environments

Next Steps