spec-driven

spec-driven is a skill for Claude Code, Codex from 90sRehem/agent-skills. It costs 241 tokens per session (4,073 once invoked), scanned A, original, no licence file.

A structured development process with four phases: Specify, Design, Tasks, and Execute. It adjusts the amount of planning to the size of the change and keeps knowledge for the team.

In plain words
What is it for?
Exploring a problem, writing specifications and designs, creating task lists, and carrying out development work with commands such as /explore and /plan.
Why use it?
It turns an unclear request into a written plan and breaks larger work into steps before implementation begins.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

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/90srehem/agent-skills/spec-driven
Any agent
npx skills add 90sRehem/agent-skills --skill spec-driven
Clone the repo
git clone --depth 1 https://github.com/90sRehem/agent-skills

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

README.md
[![agentmods](https://agentmods.dev/badge/skills/90srehem/agent-skills/spec-driven.svg)](https://agentmods.dev/skills/90srehem/agent-skills/spec-driven)
Your own site
<a href="https://agentmods.dev/skills/90srehem/agent-skills/spec-driven"><img src="https://agentmods.dev/badge/skills/90srehem/agent-skills/spec-driven.svg" alt="Measured on agentmods" height="20"></a>
Per session 241 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,073 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 5.1 $0.00241 $0.04073
Opus 5 $0.00120 $0.02037
Sonnet 5 $0.00048 $0.00815
Haiku 4.5 $0.00024 $0.00407

Measured 6d ago against content hash d13fa34f5c80, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

spec-driven 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 6d 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.

spec-driven/SKILL.md · 413 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Files

What ships with it

8 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. 6d ago First seen · 413 lines · 241 tokens per session scan A d13fa34f5c80

Subscribe to this mod's changes

spec-driven is a skill published in the GitHub repository 90sRehem/agent-skills (2 stars, last pushed 4mo ago), with no licence file. It adds 241 tokens to every session and 4,073 once invoked, about $0.0012 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.