To Features

Break an epic into independently-grabbable features using vertical slices (tracer bullets).

Principles

Durability over precision

The feature plan may stay on backlog for days or weeks. The codebase will change in the meantime. Write the feature plan so it stays useful even as files are renamed, moved, or refactored.

• Do describe interfaces, types, and behavioral contracts
• Do name specific types, function signatures, or config shapes that the agent should look for or modify
• Don't reference file paths — they go stale
• Don't reference line numbers
• Don't assume the current implementation structure will remain the same

Behavioral, not procedural

Describe what the system should do, not how to implement it. The agent will explore the codebase fresh and make its own implementation decisions.