spec-driven-development is agent-read markdown (skill) from nota-america/forgecat-agent-profiles: Creates specs before coding. Use when starting a new project, feature, or significant change and no specification exists yet. Use when drafting a PRD or requirements document with objectives and scope, or when requirements are unclear, ambiguous, or only exist as a vague idea. Use when a single requirement spans several independently testable capabilities and needs decomposing into a capability map of modules before specifying..
Indexed from public GitHub and served as immutable, content-addressed versions. Install it pinned to an exact SHA-256 with the mdr CLI, and every file is verified against the hash recorded here before it reaches your agent. The deterministic audit below grades the latest version, and the same file always earns the same grade.
What the file says
# Spec-Driven Development
## Overview
Write a structured specification before writing any code. The spec is the shared source of truth between you and the human engineer — it defines what we're building, why, and how we'll know it's done. Code without a spec is guessing.
## When to Use
- Starting a new project or feature
- Requirements are ambiguous or incomplete
- The change touches multiple files or modules
- You're about to make an architectural decision
- The task would take more than 30 minutes to implement
**When NOT to use:** Single-line fixes, typo corrections, or changes where requirements are unambiguous and self-contained.
## The Gated Workflow
Spec-driven development has four phases, preceded by a scope check (Phase 0) that activates only when one request bundles several independently testable capabilities. Do not advance to the next phase until the current one is validated.
```
SPECIFY ──→ PLAN ──→ TASKS ──→ IMPLEMENT
│ │ │ │
▼ ▼ ▼ ▼
Human Human Human Human
reviews reviews reviews reviews
```
### Phase 0: Scope Check
…
Pin to a label to follow the author's releases, or to a sha256 to freeze the exact bytes forever. Either way the resolved hash is written to mdr.lock, and mdr install reproduces it on any machine.
GET https://markdownregistry.com/api/v1/artifacts/art_jsxaik4bgp2g43nl
GET https://markdownregistry.com/api/v1/resolve?ref=nota-america/forgecat-agent-profiles/spec-driven-development
GET https://markdownregistry.com/api/v1/blob/a204d46e33d2f62c83064040083cd2348a9617dcbe2f45f12a3a57895f7bcdc3
Your agent does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
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nota-america/forgecat-agent-profiles · profiles/addyosmani/agent-skills/for-claude/.claude/skills/documentation-and-adrs/SKILL.md · Records decisions and documentation. Use when you need to document
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addyosmani/agent-skills · skills/spec-driven-development/SKILL.md · Creates specs before coding. Use when starting a new project, feature, or significant change and no specification…
a5c-ai/babysitter · library/methodologies/pilot-shell/skills/spec-driven-development/SKILL.md · Specification creation and management for the Pilot Shell methodology. Covers semantic search, clarifying questions…
shashankswe2020-ux/whoop-mcp · .github/skills/spec-driven-development/SKILL.md · Creates specs before coding. Use when starting a new project, feature, or significant change and no specification…
magnus919/agent-skills · spec-driven-development/SKILL.md · Design and run a Spec-Driven Development (SDD) pipeline for AI software factories — where structured specifications are…
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nota-america/forgecat-agent-profiles · profiles/addyosmani/agent-skills/for-forgecat/platforms/cursor/.cursor/skills/spec-driven-development/SKILL.md · Creates specs before coding. Use when starting a new project, feature, or significant change and no specification…
nota-america/forgecat-agent-profiles · profiles/addyosmani/agent-skills/for-forgecat/skills/spec-driven-development/SKILL.md · Creates specs before coding. Use when starting a new project, feature, or significant change and no specification…
nota-america/forgecat-agent-profiles · profiles/addyosmani/agent-skills/for-codex/.agents/skills/spec-driven-development/SKILL.md · Creates specs before coding. Use when starting a new project, feature, or significant change and no specification…