sdd

SDD Plugin — Spec-Driven Development for Claude Code

SDD is a Claude Code plugin that guides you through a structured, interview-driven workflow for planning and building software projects. It replaces ad-hoc prompting with a repeatable process: scope the project, produce a product requirements document, write a technical spec, then execute in sprint cycles with built-in retrospectives. Every phase produces real Markdown artifacts in your repository, so the project's knowledge base grows alongside the code.

Installation

From a plugin marketplace

# Add the marketplace (one-time)
/plugin marketplace add zabuuq/sdd-plugin

# Install the plugin
/plugin install sdd@sdd-marketplace

Local development

# Clone the repository, then run Claude Code with the plugin directory
claude --plugin-dir ./plugins/sdd

Commands

SDD provides 11 commands organized into four workflow phases.

Planning Phase

Command	Description
/sdd:onboard	One-time setup. Creates a global user profile with your communication style, git preferences, and workflow explanation preference.
/sdd:scope	Collaborative brainstorm that interviews you about your project idea, pushes back on vague thinking, and distills everything into a clear scope document.
/sdd:prd	Produces a product requirements document from the scope. User stories grouped into epics with testable acceptance criteria.
/sdd:spec	Generates a technical specification covering architecture, data models, and file structure. Also produces CLAUDE.md and AGENTS.md for your project.

Sprint Loop

Command	Description
/sdd:sprint	Pulls a logical batch of work from the PRD into a buildable sprint checklist with spec references and verification steps.
/sdd:build	Executes the sprint checklist. Supports step-by-step mode (one item per session) and autonomous mode (multiple items with checkpoints).
/sdd:iterate	Polish and improve what was built. Scopes bugs, features, or UX improvements through a brief interview and appends them to the sprint.
/sdd:reflect	Sprint-level retrospective covering process and product. Splits partial stories and recommends next steps.
/sdd:refine	Runs unvetted PRD items through a compressed planning interview. Updates spec and related documents if needed.

Project Close

Command	Description
/sdd:retro	Project-level retrospective across all sprints. Synthesizes patterns and explains how to act on plugin feedback.

Anytime

Command	Description
/sdd:feedback	Quick flag for plugin improvement ideas. Captures your note with context and returns immediately. Usage: /sdd:feedback [your note]

Workflow

Planning Phase       /sdd:onboard → /sdd:scope → /sdd:prd → /sdd:spec

Sprint Loop          /sdd:sprint → /sdd:build → /sdd:iterate → /sdd:reflect → /sdd:refine
                         ↑                                                          │
                         └──────────────────── loop back ───────────────────────────┘

Project Close        /sdd:retro

Anytime              /sdd:feedback

The planning phase runs once per project. You move through each command in order, and each one builds on the artifacts produced by the previous command.

The sprint loop repeats as many times as needed. Each cycle plans a batch of work, builds it, polishes it, reflects on the process, and refines any new items that emerged. After /sdd:reflect, you loop back to /sdd:sprint for the next batch.

/sdd:retro runs once when the project is complete. It reads all sprint retrospectives and process notes to produce a project-level summary.

/sdd:feedback can be used at any point to flag ideas for improving the plugin itself.

Quick Start

1. Install the plugin using one of the methods above.

2. Run onboard to set up your user profile:

   /sdd:onboard
   

3. Start a project by navigating to your project directory and running scope:

   /sdd:scope
   

   If you have initial ideas written up, place them in docs/seed.md before running /sdd:scope and they will be used as starting context.

4. Continue through the planning phase in order:

   /sdd:prd
   /sdd:spec
   

5. Enter the sprint loop:

   /sdd:sprint
   /sdd:build
   

6. Iterate and reflect after each sprint, then loop back for the next one.

Artifacts

SDD creates the following files in your project:

Project documents (in docs/)