API documentation is a detailed guide that explains how developers can integrate with and use an application programming interface (API). It outlines the endpoints, request and response formats, authentication methods, error codes, and usage examples. Good API documentation is crucial for helping developers understand how to interact with your solution efficiently and securely.

When submitting your solution for Salesforce security review, you must provide comprehensive API documentation. Ideally, this should be in the form of a document containing sample HTTP requests and responses, including all header values. If you prefer, you can submit a link to online API documentation, but it must include sample requests and responses. Clear and detailed documentation helps Salesforce reviewers verify your API’s security, authentication methods, and data handling practices, ensuring your solution meets Salesforce’s security standards.