modify-feature

What problem does it solve?

It helps you make a change to an existing feature without accidentally breaking adjacent contracts, data expectations, UI states, or runtime behavior.

Core Features & Use Cases

• Extension-safe modifications: add behavior, adjust how a feature works, or wire a small new component that reads existing data while auditing contract shifts first.
• Mode-based risk control: supports mode=fast, mode=balanced (default), and mode=production to choose how deep the pre-flight and verification should be.
• Guided contract + edge-case thinking: runs a seam check, contract-audit, scope boundary confirmation, and edge-case review before editing, then applies reviewer subagents after the change.

Quick Start

Use modify-feature to extend an existing feature when the change is a tweak or enhancement, for example: "Modify the existing checkout feature to also apply an extra discount when a specific promo code is present, keeping behavior stable elsewhere."