To enforce a specific Phone number format (such as an input mask), Microsoft recommends using Field controls (specifically the "Input Mask" control) which allows users to enter data matching a specific pattern. For requirements involving the manipulation of Sections of Agents case form (such as dynamically showing or hiding sections based on complex logic), Custom development using the Client API (JavaScript) is required. While Business Rules can manage field visibility, programmatic control over sections and tabs is handled via the formContext.ui object in the Client API. Workflows are server-side processes and cannot directly modify the real-time UI or formatting of an active form.

Official Vendor Documentation: Microsoft Learn. "Add the Input Mask control to columns." (Covers formatting phone numbers and strings). [Reference: Power Apps / Model-driven apps / Component reference].

Official Vendor Documentation: Microsoft Learn. "Client API Reference for model-driven apps: formContext.ui.sections." (Covers using JavaScript to manage section visibility and properties).

Official Vendor Documentation: Microsoft Learn. "Design forms for model-driven apps - Apply business logic." (Distinguishes between Business Rules, Client API/Custom Development, and Field Controls).