Skill: 02-implement-features (Engineering & UI)

📜 Source of Truth

Standard: Architecture Standards Standard: Database Standards Standard: Security Standards

🎯 Purpose

Translate the implementation_plan.md into high-performance code. This skill handles the heavy lifting: building models, services, request-handling layers, and orchestrating UI development based on user preferences. You act as a senior backend and frontend engineer.

🗣️ Agent Interaction Protocol — The Engineering Phase

[!CAUTION] As a modern agent, review the implementation_plan.md first. If any feature involves a user interface (Admin pages, frontend views), you MUST ask the user how to proceed regarding the UI before writing HTML/CSS.

First Action: Outline the features to be built based on the plan. If UI is required, present the UI options:

"I am ready to implement the features outlined in the plan. I see that we need to build some user interfaces. How would you like me to handle the UI design?"

Option A: Standard WordPress UI I will write clean, native WordPress HTML/CSS using standard admin classes and components.

Option B: Custom Frontend Stack (Vue/React/Tailwind) I will set up standard API endpoints and you or I will configure a modern JS framework to consume them.

Option C: Stitch-UI / External Generator If you have the stitch-ui skill pack installed, I will delegate the UI creation to it. (Note: only select this if you actively use stitch-ui).

Wait for the user's response to proceed.

🔄 Execution Protocol

🧭 Phase 1: Data Engineering

Models: Create src/Models/ classes for custom data. Use $wpdb->prepare for every raw query to ensure security against SQL injection.
CPTs: Ensure all post types are registered correctly in config/Config.php.

🧭 Phase 2: Logic Engineering (Services)

Extract complex business rules into src/Services/ to ensure code reusability and testability. Do not place business logic directly in the Controllers.

🧭 Phase 3: Delivery Mechanism (Controllers)

Map routes in config/Config.php.
Build "Thin Controllers" that orchestrate between Services and Views.
Implement API endpoints or Webhooks with strict input validation using the CH\Security classes.

🧭 Phase 4: UI Build (Based on User Option)

If Option A: Write the PHP Views in src/Views/ ensuring separation of concerns (no inline PHP logic beyond echo or simple loops).
If Option B: Ensure the API Controllers are perfectly structured (returning standard JSON with proper HTTP status codes).
If Option C: Output the required stitch-ui context block (JSON) to hand off the prompt to the external UI generator. Once the generator produces the HTML, integrate it into src/Views/.

🏁 Quality Gates

✅ 100% of raw SQL is encapsulated in Models (No SQL in Controllers).
✅ Business logic is decoupled from WordPress hooks and stored in Services.
✅ All user input is sanitized via CH\Security.
✅ No raw HTML is hardcoded directly inside controller methods.