coolsms-rest-sdk

coolsms-rest-sdk is a Node.js SDK for the CoolSMS REST API, enabling sending SMS, LMS, MMS messages, managing sender IDs, and handling mobile originated (MO) messages. Version 1.0.8 is the latest stable release as of 2025, with no regular release cadence; it appears to be in maintenance mode. Key differentiators include a simple callback-based interface, support for Korean SMS service providers, and built-in balance checking and message cancellation. It requires an API key and secret from CoolSMS.