sdd-mcp: Skill for Claude Code

.claude/skills/sdd-requirements/SKILL.md

sdd-requirements is a skill for Claude Code from yi-john-huang/sdd-mcp. It costs 47 tokens per session (1,077 once invoked), scanned A, original, MIT.

A requirements-writing aid for Spec-Driven Development (SDD), a process that defines what software must do before it is built. It creates requirements and acceptance criteria in EARS, a structured sentence format for reducing ambiguity.

In plain words
What is it for?
Use it when starting a feature specification, documenting user goals and success criteria, or defining requirements that later guide technical design and testing.
Why use it?
It turns a feature idea into clear, testable statements and keeps the specification aligned with the project’s context and workflow stage.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

This is yi-john-huang/sdd-mcp's own configuration. It tells Claude Code how to work on sdd-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything sdd-mcp configures →

Part of the sdd-mcp plugin — 11 skills, 6 agents shipped together

Reuse

Borrowing it

Nothing to install: this file belongs to yi-john-huang/sdd-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/yi-john-huang/sdd-mcp/master/.claude/skills/sdd-requirements/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/yi-john-huang/sdd-mcp

Made for: Claude Code.

Or install sdd-mcp, the plugin that ships this one along with the rest of its 11 skills, 6 agents.

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 sdd-requirements

README.md
[![agentmods](https://agentmods.dev/badge/skills/yi-john-huang/sdd-mcp/sdd-requirements/github.svg)](https://agentmods.dev/skills/yi-john-huang/sdd-mcp/sdd-requirements)
Your own site
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Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for sdd-requirements

Your own site · 80×15
<a href="https://agentmods.dev/skills/yi-john-huang/sdd-mcp/sdd-requirements"><img src="https://agentmods.dev/badge/skills/yi-john-huang/sdd-mcp/sdd-requirements.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 47 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,077 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 5.1 $0.00047 $0.01077
Opus 5 $0.00023 $0.00539
Sonnet 5 $0.00009 $0.00215
Haiku 4.5 $0.00005 $0.00108

Measured 11d ago against content hash 0b43697e19d0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

sdd-requirements 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 11d 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.

.claude/skills/sdd-requirements/SKILL.md · 148 lines

How it starts

The opening of the file, as written. The whole thing — 148 lines — stays where its author put it; the contents beside it link to each section on GitHub.

SDD Requirements Generation

Generate comprehensive, EARS-formatted requirements documents that integrate with the SDD (Spec-Driven Development) workflow.

Prerequisites

Before generating requirements:

  1. Feature must be initialized with sdd-init MCP tool
  2. Check current phase with sdd-status MCP tool
  3. Review project steering documents in .spec/steering/

Workflow

Step 1: Gather Context

  1. Use sdd-status MCP tool to verify feature exists and check current phase
  2. Read project context from .spec/steering/product.md if available
  3. Review the feature description from .spec/specs/{feature}/spec.json

Step 2: Analyze Requirements

Identify and document:

  • Primary user goal: What problem are we solving?
  • Target users: Who will use this feature?
  • Core functionality: What must the system do?
  • Success criteria: How do we know it works?

Step 3: Generate EARS-Formatted Requirements

Use the EARS (Easy Approach to Requirements Syntax) format for all requirements.

EARS Patterns
Pattern Syntax Use When
Ubiquitous The <system> SHALL <action> Always true requirement
Event-Driven WHEN <trigger> THEN the <system> SHALL <action> Response to event
State-Driven WHILE <state> THE <system> SHALL <action> During specific state
Optional WHERE <feature enabled> THE <system> SHALL <action> Configurable feature
Unwanted Behavior IF <condition> THEN the <system> SHALL <action> Exception handling
Examples
## FR-1: User Authentication
WHEN a user submits valid credentials
THEN the system SHALL authenticate the user and return a session token

## FR-2: Session Management
WHILE a user session is active
THE system SHALL maintain the session for up to 24 hours of inactivity

## NFR-1: Performance
The system SHALL respond to authentication requests within 200ms

Step 4: Structure the Document

Generate requirements.md with this structure:

Read the full file on GitHub · 148 lines

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. 11d ago First seen · 148 lines · 47 tokens per session scan A 0b43697e19d0

Subscribe to this mod's changes

sdd-requirements is a skill published in the GitHub repository yi-john-huang/sdd-mcp (51 stars, last pushed 1mo ago), licensed MIT. It adds 47 tokens to every session and 1,077 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 2026-08-30.

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