spec-design

spec-design is a command for Claude Code from kaze-jp/kusa. It costs 0 tokens per session (624 once invoked), scanned A, original, MIT.

A command that turns approved product requirements into a technical design document describing the proposed software structure and implementation details.

In plain words
What is it for?
Use it to document architecture, components, interfaces, data structures, and other implementation decisions for a named feature.
Why use it?
It prevents design work from starting without the required requirements and project guidance, and puts the technical plan in a standard document.

Command for Claude Code

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 commands/kaze-jp/kusa/spec-design
Clone the repo
git clone --depth 1 https://github.com/kaze-jp/kusa

Made for: Claude Code.

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-design

README.md
[![agentmods](https://agentmods.dev/badge/commands/kaze-jp/kusa/spec-design.svg)](https://agentmods.dev/commands/kaze-jp/kusa/spec-design)
Your own site
<a href="https://agentmods.dev/commands/kaze-jp/kusa/spec-design"><img src="https://agentmods.dev/badge/commands/kaze-jp/kusa/spec-design.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 624 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 $0.00000 $0.00624
Opus 5 $0.00000 $0.00312
Sonnet 5 $0.00000 $0.00125
Haiku 4.5 $0.00000 $0.00062

Measured 4d ago against content hash 982242be7997, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

spec-design 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 4d 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/commands/kiro/spec-design.md · 100 lines

How it starts

The opening of the file, as written. The whole thing — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Create Technical Design

Generate a technical design document from approved requirements.

Usage

/kiro:spec-design <feature-name>

Instructions

  1. Read the requirements from .kiro/specs/$FEATURE_NAME/requirements.md. If it does not exist, instruct the user to run /kiro:spec-requirements first.

  2. Read steering documents for technical constraints:

    • .ao/steering/tech.md for technology stack, patterns, and conventions
    • .ao/steering/structure.md for project structure and file organization
    • .ao/steering/product.md for product context
  3. Generate design.md with the following sections:

# Technical Design: <feature-name>

## Document Info
- Feature: <name>
- Status: Draft
- Created: <date>
- Requirements: ./requirements.md

## Architecture Overview
<High-level architecture description and diagram (ASCII or Mermaid)>

## Component Design

### Component: <name>
- **Purpose**: <what it does>
- **Location**: <file path>
- **Dependencies**: <other components>
- **Interface**: <public API>

### Component: <name>
...

## API Contracts

### <Endpoint/Function>
- **Signature**: <full signature>
- **Input**: <parameters with types and validation>
- **Output**: <return type and structure>
- **Errors**: <error cases and codes>
- **Example**: <usage example>

## Data Models

### <Model Name>
- **Fields**: <field definitions with types>
- **Validation**: <validation rules>
- **Relationships**: <references to other models>

## State Management
<How state flows through the system>

## Error Handling Strategy
<Error categories, recovery strategies, user-facing messages>

## Testing Strategy
- Unit test targets
- Integration test boundaries
- Edge cases to cover

## Security Considerations
<Authentication, authorization, data protection>

## Requirements Traceability
<Map each requirement ID to the design component(s) that fulfill it>
  1. Design principles to follow:
    • Every architecture decision must include rationale
    • Component boundaries must be explicit with clear interfaces
    • API contracts must specify all error cases
    • Data models must include validation rules
    • Design for testability; avoid tight coupling
    • No premature optimization

Read the full file on GitHub · 100 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. 4d ago First seen · 100 lines · 0 tokens per session scan A 982242be7997

Subscribe to this mod's changes

spec-design is a command published in the GitHub repository kaze-jp/kusa (2 stars, last pushed 3mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 624 tokens. 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.