Sooner or later every Business Central developer needs to expose data to the outside world — a website, a Power Automate flow, a mobile app, or another system. The modern way to do this is with a custom API page in AL. Unlike the older "publish as web service" approach, an API page gives you a clean, versioned, high-performance REST endpoint that follows Microsoft's OData v4 conventions. Note: If want to Check Standard API then visit Standard API List   In this tutorial we will build a simple Customer Rating API from scratch, publish it, and call it. You only need VS Code with the AL extension and a Business Central sandbox. Step 1: The table we will expose We will use a small custom table so the example is self-contained. table 50100 "Customer Rating" { DataClassification = CustomerContent; fields { field(1; "No."; Code[20]) { } field(2; "Customer No."; Code[20]) { TableRelation = Cus...