A Page Designer Page Type consists of a metadata definition plus a corresponding JavaScript implementation. The rendering behavior itself belongs in the page-typeJavaScript file, which must expose arender()function.

Salesforce states that the script file must have the same base name and location as the Page Designer meta-definition file, using.jsrather than.json. The script'srenderfunction receives aPageScriptContextand must return the resulting markup as a string. It commonly renders an ISML template usingdw.util.Template, and the template can in turn render the page's regions.

The metadata JSON describes the Page Type's declarative configuration---such as its attributes and regions---but does not implement rendering through a'render'property. A conventional SFRA controller route can invokePageMgr.renderPage()to initiate rendering, but that controller does not define the actual Page Type rendering logic.

This separation allows Page Designer to manage page composition while the JavaScript implementation controls the output representation.

Study Guide reference:Application Development --- Page Designer Page Types, page metadata,render()functions,PageScriptContext, and Page Designer rendering.

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