When defining a new custom endpoint in Salesforce Commerce Cloud, what is the first step a developer should take?

Creating a new cartridge to house the endpoint is indeed the first step a developer should take when defining a new custom endpoint in Salesforce Commerce Cloud. Cartridges are the fundamental building blocks of a Salesforce Commerce Cloud application; they contain the code, configurations, and resources for your custom features, including API endpoints.

By setting up a new cartridge, you establish a structured environment where the endpoint's code and logic can reside. This organization not only allows for better management and modularization of code but also ensures that your custom functionality is logically separated from existing features, making it easier to develop, test, and maintain.

While defining the endpoint's path in the API documentation, modifying server-side controllers to handle requests, and registering the endpoint in the Business Manager are important steps in the process, they would typically follow the creation of the cartridge. Without a dedicated cartridge for the endpoint, the subsequent steps cannot be implemented effectively. Thus, starting with the cartridge is crucial for a properly structured development workflow in Salesforce Commerce Cloud.