Spec Driven Codex

A lightweight, specification-driven development workflow tailored for the Codex CLI. Run npx spec-driven-codex init to scaffold the .sdd workspace and install Codex prompts that guide you from discovery to delivery. Use npx spec-driven-codex upgrade any time you need to refresh the prompts with the latest templates.

• Single command setup – init bootstraps everything you need
• Safe re-runs – existing Codex prompts are kept as-is while .sdd/README.md is refreshed every run
• One-step upgrades – upgrade force-installs the latest prompt copies and refreshes .sdd/README.md
• Codex-ready prompts – English by default, Japanese with --locale ja
• Always in sync – Spec artifacts live under .sdd/ for the entire flow

Quick Start

# Inside your project root
npx spec-driven-codex init

# Launch Codex CLI and run the prompts in order
codex
> /sdd-steering
> /sdd-requirements
> /sdd-highway      # optional fast lane for design -> tasks -> implementation
> /sdd-design
> /sdd-tasks
> /sdd-implement
> /sdd-archive

Skip the manual /sdd-design, /sdd-tasks, and /sdd-implement entries if you already ran /sdd-highway.

Pass --locale ja to init if you prefer Japanese templates and prompts:

npx spec-driven-codex init --locale ja

To refresh the prompt templates later on, run:

npx spec-driven-codex upgrade

CLI Command

Command	Description
npx spec-driven-codex init [--locale ja]	Creates .sdd/ scaffolding, localized templates, installs Codex prompts (existing prompt files are left untouched) and always refreshes .sdd/README.md.
npx spec-driven-codex upgrade [--locale ja]	Force-installs the latest Codex prompt templates into ~/.codex/prompts (overwrites without confirmation) and refreshes .sdd/README.md.

Codex CLI Prompts

Once the workspace is initialized, run the Codex CLI prompts in sequence to progress through the specification-driven flow:

• /sdd-steering — Capture product context, stakeholders, and risks.
• /sdd-requirements — Define requirements and acceptance criteria. Update .sdd/description.md with the problem and feature summary before running this prompt so the requirements stay grounded in the latest context.
• /sdd-highway — Optional fast lane that triggers /sdd-design, /sdd-tasks, and /sdd-implement back-to-back.
• /sdd-design — Document architecture and implementation strategy.
• /sdd-tasks — Break the design into actionable tasks.
• /sdd-implement — Implement every task with tests and refactors.
• /sdd-archive — Summarize outcomes, lessons learned, and next steps.

Working with Codex CLI

Codex CLI occasionally prints a high-level plan to the console before it actually runs the command. When that happens—or when the CLI explicitly asks for approval—simply type ok (or another affirmative response) and press Enter to let the flow continue.

Generated Structure

project/
├── .sdd/
│   ├── README.md            # Locale-aware command overview
│   ├── description.md       # Feature description template
│   ├── target-spec.txt      # Active specification name
│   ├── steering/            # Discovery notes (/sdd-steering)
│   └── specs/               # Specs, tasks, archives, and artifacts
│       └── archives/
└── ~/.codex/prompts/
    ├── sdd-steering.md
    ├── sdd-requirements.md
    ├── sdd-highway.md
    ├── sdd-design.md
    ├── sdd-tasks.md
    ├── sdd-implement.md
    └── sdd-archive.md

Need the Japanese documentation? Check README.ja.md.

Looking for updates in another language? Contributions that keep both documents aligned are welcome.

License

MIT

Acknowledgements

This workflow draws inspiration from the open-source specification-driven tooling at gotalab/cc-sdd. Many thanks to the maintainers and contributors for sharing their approach.