Feature Doc Rubric

Feature Doc Rubric

A forcing function. Tick every checkbox before declaring the spec complete.

The doc you produce is a live spec — descriptive, short, and permanently useful as project memory and AI context. It is not a changelog. A changelog answers "what commits landed?"; a live spec answers "what does this feature do, and why does it work this way?"

If a conflict arises between rules, the §2 length budget wins — every section is gated by the 100-line ceiling, so trim before you reach for an extra subsection.

1. Source of truth

• Read the squashed commit at the latest dev/done-NNN (or HEAD if /done just ran). This is the only diff that ships.
• Read the archived plan at docs/archive/<slug>.md. This is the only authority on goal, scope, and design rationale.
• Do NOT pull from working-tree changes, unsquashed commits, or unrelated history.
• Do NOT invent rationale. If the plan does not state why, omit the bullet — never reverse-engineer reasons from the diff.
• If the squashed commit and the archived plan disagree on a fact, flag the disagreement; do not pick a side silently.

2. Length & tone

• Total length < 100 lines including blanks and headers. Length is the budget — extracting only durable signal is the discipline.
• Descriptive prose, not implementation walkthrough. A reader who has never seen the code should understand what changed and why.
• No code blocks longer than 5 lines. A code reference belongs in the source, not the spec.
• No file:line citations. They drift; refer to features, agents, commands, or surfaces by name.
• Plain language. Prefer the normal word over the jargon word when both fit.
• No emojis unless the user's project style already uses them.

3. Required sections

The spec has exactly these top-level sections, in this order. Adding new top-level sections is a fail. Skipping an applicable section is a fail.

• # <Feature Name> — title only, plain words, not the slug.
• Status line — one block-quoted line: iteration tag (dev/done-NNN), date, and a one-sentence summary.
• ## What it does — 2–3 paragraphs in plain language. What user-visible behavior is added or changed. Lead with the user, not the implementation.
• ## Design decisions — bulleted list. Each bullet: what was chosen, what was rejected, why. If the plan records no rationale for a decision, omit that bullet rather than fabricate.
• ## Scope — **In:** / **Out:** split. Every **Out:** bullet must state why deferred (premature, separate concern, awaiting second use case, etc.).
• ## Relationship to existing system — what this builds on, replaces, mirrors, or interacts with. Name features, agents, commands, or doc surfaces by name.
• ## Behavior changes — only if existing behavior was modified. Each bullet: prior behavior → new behavior → why. Omit the section entirely when the feature is purely additive.

4. Drift sweep across existing docs

This is the section the rubric exists to enforce. A live spec that ignores docs the change has invalidated is worse than no spec at all.

• Decide whether this feature changed existing behavior. Anything that contradicts a claim already documented somewhere counts as a behavior change.
• If purely additive: state "no drift" explicitly in the drift report and skip the rest of this section. That is a valid result.
• If behavior changed: enumerate every doc surface that could plausibly be affected:
  • CLAUDE.md (all of it — routing tables, agent lists, skill lists, hook descriptions, command tables)
  • README.md
  • Every existing file under docs/features/**
  • Every other top-level *.md in the repo (TDD.md, QUALITY_TOOLING.md, CHANGELOG.md if user-maintained, etc.)
• For each candidate doc, read it and grep for claims the new commit contradicts. Be exhaustive — partial sweeps create false confidence.
• Update only the claims that drifted. Doc churn for its own sake is noise.
• Update drifted docs in the same commit as the new spec — drift left unfixed defeats the purpose of the live spec.
• If a doc is silent on the affected area but should mention it, list it as 🆕 in the drift report and ask the orchestrator before silently inserting content.

5. Verification (before commit)

• Every claim in the spec traces to the squashed diff or the archived plan. No speculation.
• Every **Out:** bullet has a stated reason.
• If a ## Behavior changes section exists, every bullet names the prior behavior, the new behavior, and why.
• Drift sweep ran. Result is either "no drift" or a list of updated docs — never absent.
• Spec reads cold: a reader six months from now, with no other context, can answer "what is this?" and "why does it work this way?"
• Total length still < 100 lines after the final pass.
• Staged files: only the new spec and any drifted docs. Never git add -A.