/feature — author one feature file (the atom)

You produce or revise exactly one file in Product/Features/ that conforms to the feature schema. Be strict: a feature is not done until it has a complete user story, at least three testable acceptance criteria, and a classification with a rationale.

Procedure

1. Locate the product root. Find Product/Features/ from the current directory. If Product/ doesn't exist, tell the user to run /intent first (or offer to create the folder if they just want to draft features directly).
2. New or revise?
   • Revise: if the user names an existing feature (by id or title), read that file and edit in place — keep the id stable.
   • New: scan Features/F*.md, find the highest F<NNN>, assign the next id. Filename = F<NNN>-<kebab-slug>.md.
3. Gather the content. You need: title, persona, capability, benefit (the user story); ≥3 acceptance criteria; classification; rationale; priority; status; and any dependencies on other features (depends_on). If the caller (e.g. /innovate) supplied these, use them. If invoked standalone with gaps, ask the user one focused question at a time (use AskUserQuestion for the classification fork). Do not invent a user story from nothing — ask.
4. Classify (mirror /classify's rubric):
   • Apply the decision test: "If a competitor shipped this exact feature tomorrow, would we lose our edge?" → innovation. "Would every competitor's product have this too?" → implementation.
   • Set innovation_weight: implementation → 0; innovation → 1–100 by how much of the moat it carries.
   • For innovation features, set contributes_to to a UVP id from Product/innovation.md (read it if present). If you can't point to a UVP element, that's a signal the feature may actually be implementation — challenge it.
   • Write a one-sentence classification_rationale.
5. Write the file using the schema below (canonical copy lives at the plugin's templates/feature.md). Validate before finishing:
   • User story has all three clauses (As a… / I want… / so that…).
   • ≥3 acceptance criteria, each observable and testable (Given/When/Then, or a plain checkbox where GWT is awkward).
   • classification + innovation_weight + classification_rationale all present and mutually consistent (implementation ⇒ weight 0).
6. Refresh the index. Note that Product/features-index.md is now stale; offer to run /classify (regenerates the ranked index) or /product-status.

Schema (reproduce exactly)

---
id: F00N
title: Short feature name
classification: innovation | implementation
innovation_weight: 0-100        # implementation = 0; innovation = 1-100
classification_rationale: One sentence.
contributes_to: UVP-x           # innovation features only
priority: must | should | could | wont
status: proposed | validated | building | done
risk_retired:
created_by_stage: ideation | innovation | manual
depends_on: [F00X]              # optional, structured — features this builds on
---

## User story
As a **<persona>**, I want **<capability>**, so that **<benefit>**.

## Acceptance criteria
- [ ] **Given** <context>, **when** <action>, **then** <result>.
- [ ] ...
- [ ] ...

## Notes & open questions
- ...