The agent harness performance optimization system. Skills, instincts, memory, security, and research-first development for Claude Code, Codex, Opencode, Cursor and beyond.
Spec-driven workflow harness for AI coding agents
cc-sdd installs a Kiro-inspired spec workflow as Agent Skills for supported coding agents. It turns an idea into discovery, requirements, design, tasks, and autonomous implementation, with review and auto-debug loops for each task.
Builders who want one spec workflow that works across Claude Code, Codex, Cursor, and other supported agents.
You can move from approved spec to long-running implementation without re-explaining scope at every step.
What it does
Discovery routing
`/kiro-discovery` decides whether to extend an existing spec, create a new one, split work into multiple specs, or implement directly.
Requirements, design, and tasks flow
It generates `brief.md`, `requirements.md`, `design.md`, and `tasks.md` so the work can move through clear phase gates.
Autonomous task execution
`/kiro-impl` runs one task at a time with a fresh implementer, an independent reviewer, and auto-debug when blocked or rejected.
Boundary-first spec discipline
Design and task files carry file structure plans, boundary notes, and dependency annotations to catch boundary violations.
Multi-agent skills packaging
The same 17-skill set is packaged for Claude Code, Codex, Cursor, Copilot, Windsurf, OpenCode, Gemini CLI, and Antigravity.
Customizable templates and rules
Project-specific templates and rules live under `{{KIRO_DIR}}/settings/`, so teams can adapt the workflow to their own standards.
How to get it
- 1Run
cd your-project npx cc-sdd@latest
- 2The default installs Claude Code Skills with English docs. To pick another agent or…
npx cc-sdd@latest --codex-skills --lang ja # Codex, Japanese npx cc-sdd@latest --cursor-skills --lang zh-TW # Cursor IDE, Traditional Chinese
- 3Then, in your agent
/kiro-discovery <idea>
- 4Run
npx cc-sdd@latest --lang ja # Japanese npx cc-sdd@latest --lang zh-TW # Traditional Chinese npx cc-sdd@latest --lang es # Spanish # Supports: en, ja, zh-TW, zh, es, pt, de, fr, ru, it, ko, ar, el
- 5Run
# Preview changes before applying npx cc-sdd@latest --dry-run # Custom specs directory npx cc-sdd@latest --kiro-dir docs
README
cc-sdd: Long-running spec-driven implementation for AI coding agents
Turn approved specs into long-running autonomous implementation
One command installs an agentic SDLC workflow as Agent Skills: discovery, requirements, design, tasks, and autonomous implementation with per-task independent review. Works across 8 AI coding agents, with the same 17-skill set on each.
👻 Kiro-inspired. Similar spec-driven, agentic SDLC style as Kiro IDE. Existing Kiro specs remain compatible and portable.
What's new in v3.0
cc-sdd v3.0 is a rework around Agent Skills and long-running autonomous implementation.
/kiro-discoveryas the new entry point. Discovery routes new work into one of: extend an existing spec, implement directly with no spec, create one new spec, decompose into multiple specs, or mixed decomposition. It writesbrief.mdand, when needed,roadmap.md, so you can resume a workstream without re-explaining scope./kiro-implfor long-running autonomous implementation. Each task gets a fresh implementer running TDD (RED → GREEN) behind a feature flag, an independent reviewer, and an auto-debug pass that investigates root causes in a clean context when the implementer is blocked or the reviewer rejects twice. Learnings from earlier tasks propagate forward via## Implementation Notesintasks.md. 1 task per iteration, safe to re-run after interruption.- Boundary-first spec discipline.
design.mdnow includes a File Structure Plan that drives task boundaries. Tasks carry_Boundary:_and_Depends:_annotations. Review and validation look for boundary violations, not just style issues. /kiro-spec-batchfor multi-spec initiatives. Turn a roadmap into multiple specs in parallel, with cross-spec review to catch contradictions, duplicated responsibilities, and interface mismatches.- Agent Skills across 8 coding agents. 17 skills per install, loaded on demand (progressive disclosure). Claude Code and Codex are stable; Cursor, Copilot, Windsurf, OpenCode, Gemini CLI, and Antigravity are in beta. No external dependencies; subagents are spawned through each platform's native primitive.
Full skills-mode workflow and /kiro-impl internals: Skill Reference.
Upgrading from v1.x or v2.x? See the Migration Guide.
Why cc-sdd?
cc-sdd treats the spec as a contract between parts of the system, not a master command document handed to the agent. Code remains the source of truth. Specs make the boundaries between parts of the code explicit so humans and agents can work in parallel without constant synchronization.
The bet: explicit contracts at the right granularity let AI-driven development at team scale move faster, not slower. Agents write the spec, humans approve the contract at phase gates, code is what ships.
Boundaries are not overhead. They are what lets you move freely inside while protecting the outside.
Full rationale, trade-offs, and when-to-use / when-not-to-use: Why cc-sdd? A philosophy note.
Quick Start
cd your-project
npx cc-sdd@latest
The default installs Claude Code Skills with English docs. To pick another agent or language:
npx cc-sdd@latest --codex-skills --lang ja # Codex, Japanese
npx cc-sdd@latest --cursor-skills --lang zh-TW # Cursor IDE, Traditional Chinese
Supports 8 AI coding agents (Claude Code and Codex stable; Cursor, Copilot, Windsurf, OpenCode, Gemini CLI, and Antigravity in beta) and 13 languages. See Supported Agents for the full list.
Then, in your agent:
/kiro-discovery <idea>
Not sure where to start? Start with kiro-discovery. It routes your request and tells you what command to run next.
Common workflows
| You want to... | Skills mode |
|---|---|
| Start a new feature or product-sized idea | kiro-discovery → kiro-spec-init → kiro-spec-requirements → kiro-spec-design → kiro-spec-tasks → kiro-impl |
| Extend an existing system | kiro-steering → kiro-discovery or kiro-spec-init → optional kiro-validate-gap → kiro-spec-design → kiro-spec-tasks → kiro-impl |
| Break down a large initiative | kiro-discovery → kiro-spec-batch |
| Implement a small change with no spec | kiro-discovery → direct implementation |
Legacy /kiro:* command modes are still available (--claude, --cursor, etc.) but are deprecated. See the Migration Guide for the upgrade path.
For larger approved task sets, run kiro-impl to start autonomous implementation with per-task subagent spawn, independent review, and auto-debug on failure.
See It In Action
Example: build a new Photo Albums feature.
/kiro-discovery Photo albums with upload, tagging, and sharing
# discovery writes brief.md (and roadmap.md when multi-spec) and suggests the next command
/kiro-spec-init photo-albums
/kiro-spec-requirements photo-albums
/kiro-spec-design photo-albums
/kiro-spec-tasks photo-albums
/kiro-impl photo-albums
# autonomous: fresh implementer, independent reviewer, and auto-debug per task
Typical spec outputs (under 10 minutes):
requirements.md: EARS-format requirements with acceptance criteria.design.md: architecture with Mermaid diagrams and a File Structure Plan.tasks.md: implementation tasks with boundaries and dependency annotations.
Then /kiro-impl runs the tasks autonomously with TDD (RED → GREEN) behind feature flags, an independent reviewer pass, and auto-debug on failure.

Supported Agents
All 8 skills variants ship the same 17-skill set. The difference is how much real-world usage each platform integration has seen.
| Agent | Skills mode | Stability | Legacy mode |
|---|---|---|---|
| Claude Code | --claude-skills | Stable | --claude / --claude-agent (deprecated) |
| Codex | --codex-skills | Stable | --codex (blocked) |
| Cursor IDE | --cursor-skills | Beta | --cursor (deprecated) |
| GitHub Copilot | --copilot-skills | Beta | --copilot (deprecated) |
| Windsurf IDE | --windsurf-skills | Beta | --windsurf (deprecated) |
| OpenCode | --opencode-skills | Beta | --opencode / --opencode-agent (deprecated) |
| Gemini CLI | --gemini-skills | Beta | --gemini (deprecated) |
| Antigravity | --antigravity | Beta (experimental) | — |
| Qwen Code | — | — | --qwen |
"Beta" does not mean "missing features", the 17 skills and templates are identical across all 8 platforms. It means the platform integration (subagent spawn behavior, ergonomics, SKILL.md loading) has had less real-world usage than Claude Code and Codex, and edge cases may still surface. Please report issues if you hit any.
Advanced Installation
Skills mode (recommended)
npx cc-sdd@latest # Claude Code Skills (default)
npx cc-sdd@latest --claude-skills # Claude Code Skills
npx cc-sdd@latest --codex-skills # Codex Skills
npx cc-sdd@latest --cursor-skills # Cursor IDE Skills (beta)
npx cc-sdd@latest --copilot-skills # GitHub Copilot Skills (beta)
npx cc-sdd@latest --windsurf-skills # Windsurf IDE Skills (beta)
npx cc-sdd@latest --opencode-skills # OpenCode Skills (beta)
npx cc-sdd@latest --gemini-skills # Gemini CLI Skills (beta)
npx cc-sdd@latest --antigravity # Antigravity Skills (beta, experimental)
Legacy modes (deprecated)
npx cc-sdd@latest --claude # Claude Code commands (use --claude-skills)
npx cc-sdd@latest --claude-agent # Claude Code subagents (use --claude-skills)
npx cc-sdd@latest --cursor # Cursor IDE commands (use --cursor-skills)
npx cc-sdd@latest --copilot # GitHub Copilot prompts (use --copilot-skills)
npx cc-sdd@latest --windsurf # Windsurf IDE workflows (use --windsurf-skills)
npx cc-sdd@latest --opencode # OpenCode commands (use --opencode-skills)
npx cc-sdd@latest --opencode-agent # OpenCode subagents (use --opencode-skills)
npx cc-sdd@latest --gemini # Gemini CLI commands (use --gemini-skills)
npx cc-sdd@latest --codex # Codex (blocked, use --codex-skills)
npx cc-sdd@latest --qwen # Qwen Code
Language
npx cc-sdd@latest --lang ja # Japanese
npx cc-sdd@latest --lang zh-TW # Traditional Chinese
npx cc-sdd@latest --lang es # Spanish
# Supports: en, ja, zh-TW, zh, es, pt, de, fr, ru, it, ko, ar, el
Advanced options
# Preview changes before applying
npx cc-sdd@latest --dry-run
# Custom specs directory
npx cc-sdd@latest --kiro-dir docs
Customization
Edit templates and rules in {{KIRO_DIR}}/settings/ to match your team's workflow.
templates/: document structure for requirements, design, tasks.rules/: AI generation principles and judgment criteria.
Common use cases: PRD-style requirements, API and database schemas, approval gates, JIRA integration, domain-specific standards.
Customization Guide has practical examples with copy-paste snippets.
Documentation
| Guide | What you will learn | Links |
|---|---|---|
| Skill Reference | Skills-mode workflow, supporting skills, /kiro-impl subagent flow, Skills vs --claude-agent | English | 日本語 |
| Command Reference | Legacy /kiro:* commands with detailed usage, parameters, and examples | English | 日本語 |
| Customization Guide | Practical examples: PRD requirements, frontend/backend designs, JIRA integration | English | 日本語 |
| Spec-Driven Guide | Complete workflow methodology from requirements to implementation | English | 日本語 |
| Why cc-sdd? | Design rationale, trade-offs, when the tool fits and when it does not | English | 日本語 |
| Claude Subagents | Legacy --claude-agent install target and its spec-quick subagent flow | English | 日本語 |
| Migration Guide | Upgrading from v1.x / v2.x | English | 日本語 |
Related resources
Articles & presentations
- Kiroの仕様書駆動開発プロセスをClaude Codeで徹底的に再現した (Zenn, Japanese)
- Claude Codeは仕様駆動の夢を見ない (Speaker Deck, Japanese)
External resources
- Kiro IDE: enhanced spec management and team collaboration.
- Kiro's Spec Methodology: the original spec-driven development methodology.
License
MIT License
Files in the repo
- .agents
- .github
- .kiro
- assets
- docs
- tools
- .gitignore
- AGENTS.md
- CHANGELOG.md
- CLAUDE.md
- LICENSE
- README.md
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