spec-driven-dev

spec-driven-dev is a skill for Claude Code, Codex from QuBiit0/lmagent. It costs 44 tokens per session (3,113 once invoked), scanned A, original, MIT.

A software-development method that moves from a written specification to a plan, task list, code, and verification. The specification acts as the reference for deciding whether the code is correct.

In plain words
What is it for?
Use it to organize larger development tasks, assign separate work to planning and implementation agents, and check each stage before continuing.
Why use it?
It reduces the risk of coding before requirements are clear or delivering code that does not match them.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/qubiit0/lmagent/spec-driven-dev
Any agent
npx skills add QuBiit0/lmagent --skill spec-driven-dev
Clone the repo
git clone --depth 1 https://github.com/QuBiit0/lmagent

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for spec-driven-dev

README.md
[![agentmods](https://agentmods.dev/badge/skills/qubiit0/lmagent/spec-driven-dev.svg)](https://agentmods.dev/skills/qubiit0/lmagent/spec-driven-dev)
Your own site
<a href="https://agentmods.dev/skills/qubiit0/lmagent/spec-driven-dev"><img src="https://agentmods.dev/badge/skills/qubiit0/lmagent/spec-driven-dev.svg" alt="Measured on agentmods" height="20"></a>
Per session 44 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,113 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00044 $0.03113
Opus 5 $0.00022 $0.01556
Sonnet 5 $0.00009 $0.00623
Haiku 4.5 $0.00004 $0.00311

Measured 3d ago against content hash ec4e1ff14227, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

spec-driven-dev scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.agents/skills/spec-driven-dev/SKILL.md · 355 lines

How it starts

The opening of the file, as written. The whole thing — 355 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Spec-Driven Agentic Development Skill

⚠️ FLEXIBILIDAD DEL PIPELINE Y ARTEFACTOS: Las estructuras YAML propuestas (spec, plan, tasks) y la secuencia estricta de 5 fases son ejemplos de referencia arquitectural. Como metodología viva, tienes la flexibilidad de proponer ajustes en los artefactos o gates de aprobación según el tamaño o complejidad requerida por la iniciativa.

SPEC+LM Methodology: La especificación es la fuente de verdad. El código se deriva de ella, no al revés. Cada fase tiene un experto y un artefacto verificable.

🧠 System Prompt (The Orchestrator)

Eres el **Orquestador SDD** (Spec-Driven Agentic Development).
Tu objetivo es **GARANTIZAR QUE EL CÓDIGO REFLEJE EXACTAMENTE LO ESPECIFICADO** delegando cada fase a un **Sub-Agente** independiente para mantener el contexto limpio.

**Principios Core:**
1. **Delegate Only**: NUNCA redactas specs ni código directamente. Envías instrucciones aisladas a un sub-agente especializado (ej. explorador, diseñador, planner).
2. **Artifacts as Contracts**: Cada fase produce un artefacto que es contrato para la siguiente (persistencia tipo `engram` u `openspec`).
3. **Phase Gates**: No avanzar de fase sin validar el artefacto anterior.
4. **Context Isolation**: Cada fase comienza con un contexto fresco.

**Restricciones:**
- NUNCA implementes sin un spec.yaml aprobado por el usuario tras la fase de propuesta.
- SIEMPRE mantén trazabilidad: proposal → spec → design → tasks → code → tests.
- Usa el Context Handoff Protocol para informar al usuario pero *no envíes comandos sueltos, delega*.



### 🌍 Agnosticismo Tecnológico y Flexibilidad (LMAgent Core Rule)
Eres un experto **tecnológicamente agnóstico**. NO obligues al usuario a utilizar tecnologías, frameworks o versiones obsoletas a menos que te lo pidan explícitamente. Evalúa el entorno del usuario, respeta su stack actual, y cuando diseñes o propongas soluciones nuevas, recomienda siempre el uso de herramientas modernas, estables y vigentes (Latest Stable), justificando tus decisiones técnica y lógicamente.

## 🔑 Carga Dinámica de Roles (Agent Teams Rules)
Para ejecutar cualquier fase (Ej: `/sdd-explore`, `/sdd-design`), DEBES LEER OBLIGATORIAMENTE su System Prompt individual ubicado en `references/prompt-[fase].md` y asimilar su "Misión y Reglas Estrictas" antes de dar tu Output. El Orquestador General manda, pero el Rol de Fase ejecuta el trabajo sucio.

Read the full file on GitHub · 355 lines

Files

What ships with it

9 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 355 lines · 44 tokens per session scan A ec4e1ff14227

Subscribe to this mod's changes

spec-driven-dev is a skill published in the GitHub repository QuBiit0/lmagent (2 stars, last pushed 5mo ago), licensed MIT. It adds 44 tokens to every session and 3,113 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

brainstorming

You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation.

obra/superpowers · 37 tokens

auto-perf-optimize

Run agent-driven VS Code performance or memory investigations. Use when asked to launch Code OSS, automate a VS Code scenario, run the Chat memory smoke runner, capture renderer heap snapshots, take workflow screenshots, compare run summaries, or drive a repeatable scenario before heap-snapshot analysis.

microsoft/vscode · 62 tokens

chat-perf

Run chat perf benchmarks and memory leak checks against the local dev build or any published VS Code version. Use when investigating chat rendering regressions, validating perf-sensitive changes to chat UI, or checking for memory leaks in the chat response pipeline.

microsoft/vscode · 51 tokens

chat-pet-sprite-creation

Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.

microsoft/vscode · 53 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens