Use when starting any feature or product slice expected to take more than a session — when the user describes something to build ("facciamo", "creiamo", "voglio una pagina/feature"), before implementation planning, or when a goal phase lacks a written spec.
Installs into .claude/skills of the current project.
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---
name: spec-first
description: Use when starting any feature or product slice expected to take more than a session — when the user describes something to build ("facciamo", "creiamo", "voglio una pagina/feature"), before implementation planning, or when a goal phase lacks a written spec.
---
# Spec First
## Overview
The spec shape below is salvaged from this workspace's own best specs (the Feb 2026 MVP voice
pipeline, a research-site brief) — the SpecKit engine is retired, the shape earned its
keep. A spec is the PI's judgment made editable; the draft saves typing, the edit IS the judgment.
## The shape (write to `specs/<slug>.md`)
```
# <Feature name>
## Overview — one paragraph: what and why now
## User stories — each: As/I want/so that + Acceptance criteria that are
OBSERVABLE BEHAVIORS (a tester could check each box)
## Read first — table: What | Where | Why (files the implementer must
understand before writing code)
## Non-goals — what this slice deliberately does NOT do
## Hard constraints — tech, UX, budget, deadline ("demo tra X giorni" goes HERE,
not in a firefight message later)
## Open questions — every inference marked [ASSUMED: …]; unresolved = not approved
```
## Rules
- Acceptance criteria must be checkable without interpretation ("routing happens silently — no
voice prompt about choosing a mode" is checkable; "good UX" is not).
- Draft fast, mark every guess `[ASSUMED]`, and hand back for editing. **Never proceed to
implementation with unresolved `[ASSUMED]` markers** — the user's edit of those markers is
the load-bearing judgment, not a formality.
- The Read-first table is for the NEXT agent, not the user: real paths, one-line why each.
- Slice scope: if the stories exceed what SDD can verify in a few tasks, split the spec.
## When NOT to use
Bug fixes (skill: root-cause), one-file changes, research experiments (predictions +
directive files own that lane).
