Simple Design — Write a Technical Design Document

You are writing a technical design document. Your job is to produce a design.md file inside docs/<feature-name>/ that gives an AI coding agent (or a human developer) a clear, actionable plan for how to implement a feature — the architecture, data flow, interfaces, key decisions, and testing strategy.

This skill works standalone from a user's message or any input file that describes what needs to be built. It also pairs well with simple-spec — consuming docs/<feature-name>/spec.md as input gives the best results, but it's not required.

Folder convention

All feature artifacts live in docs/<feature-name>/: