GitHub Spec Kit

Build with a spec, fix a bug, or assess an idea — with your coding agent.

Spec Kit gives your coding agent structured processes that keep intent and evidence ahead of implementation. Start with Spec-Driven Development (SDD), bug fixing, or idea assessment. Run a process step by step, automate it, or shape one of your own — including processes beyond software development.

Install Spec Kit Choose your process

Choose your process

What you need	Start here	What you get	Command reference
Build a feature or application	Spec-Driven Development	A specification carried through planning, implementation, and convergence	Agentic SDD
Diagnose and repair broken behavior	Bug fixing	An assessed cause, scoped fix, and recorded verification	Agentic Bug Fix
Decide whether an idea deserves investment	Idea assessment	An evidence-backed go, clarify, or stop decision	Agentic Idea Assessment

These are independent entry points, not mandatory phases. SDD ships in core. Bug fixing and assessment are bundled, opt-in extensions. Assessment can stand alone; a decision to proceed does not automatically start implementation.

See how the Spec Kit project runs its agentic SDLC and where it uses Spec Kit itself.

Adding Spec Kit to an established codebase? Start with the existing-project guide.

Specify CLI

The Specify CLI (specify) initializes projects and manages integrations, extensions, presets, workflows, and bundles. Process commands such as /speckit.specify run inside your coding agent, not in the terminal; see command invocation for your agent's syntax and the command references above for arguments, artifacts, and quality gates.

Shared capability	Reference
Initialize projects, check installed tools, and inspect version and system information	Core Commands
Expose supported Specify operations to MCP clients through an experimental local stdio server	MCP Server
Inspect visible commands, templates, scripts, and hooks, including winning and hidden composition layers	Artifacts
Discover components through built-in, community, or private catalogs and understand source priority and trust	Catalogs

Spec-driven by default

The core SDD process ships ready to use: Specify → Plan → Tasks → Implement → Converge.

Define what to build before building it. Rich templates, quality checklists, and cross-artifact analysis come out of the box. Each phase produces a Markdown artifact that feeds the next — giving your AI coding agent structured context instead of ad-hoc prompts.

Walk through the workflow →

Use any coding agent

38 integrations — Copilot, Gemini, Codex, Kilo Code, Zed, Claude, Forge, Kiro, and more. Switch freely between agents with a single command. No lock-in.

Run specify init with your agent of choice and Spec Kit sets up the right command files and directory structures automatically. If your agent isn't listed, the generic integration is an escape hatch for any tool.

See all integrations →

Make it your own

157 community extensions (90+ authors), 33 presets, and growing. Tune the core process with presets, extend it with extensions, orchestrate it with workflows, and package it all up as bundles you can share — or replace the process entirely. The process itself lives in these building blocks, so you're never locked to SDD, or even to software.

Including entirely different processes:

AIDE — 7-step AI-driven engineering lifecycle
Canon — baseline-driven workflows (spec-first, code-first, spec-drift)
Product Forge — product-management-oriented SDD
FX→.NET — end-to-end .NET Framework migration across 7 phases
MAQA — multi-agent orchestration with quality assurance gates
Fiction Book Writing — novels and long-form fiction, from story bible to submission

Presets → Extensions → Workflows → Bundles →

Integrate into your organization

Works offline, behind firewalls, and on Windows, macOS, and Linux. Host your own catalogs to curate what integrations, extensions, presets, workflows, and bundles your organization discovers and recommends.

Community extensions like CI Guard and Architecture Guard add compliance gates and governance that fit the way your team already works.

Enterprise / Air-Gapped → Catalogs →

Built by the community

270+ contributors power the Spec Kit ecosystem — from core integrations to entirely new processes. Anyone can create and publish an extension, preset, or workflow.

130K+ GitHub stars

270+ Contributors

38 Integrations

157 Extensions

33 Presets

7 Friends projects

Presets · Walkthroughs · Friends

Explore the docs

Spec Kit's Agentic SDLC How this project assesses, builds, tests, ships, and repairs changes Spec-Driven Development Define, plan, implement, and converge on a feature Bug Fixing Assess the cause, apply a scoped fix, and verify the result Idea Assessment Research an idea and decide whether it deserves investment Adapt Spec Kit to your process Adapt a process, add capabilities, or package a role-based setup Existing Projects Adopt Spec Kit safely in an established codebase Upgrade Keep an existing Spec Kit project current across releases Core Commands Initialize projects, check tools, and inspect version and system information Community Extensions, presets, walkthroughs, and friend projects Develop Spec Kit locally Run, debug, and check changes to Spec Kit itself How to Understand and apply Spec Kit practices to your project work History How Spec Kit grew from its SDD foundation into an extensible process harness

uv tool install specify-cli
specify init my-project --integration copilot

Ready to start? Choose your process.

Component	Guide	CLI reference
Integrations	Agent setup and delivery	Integration management
Extensions	Add capabilities, commands, and hooks	Extension management
Presets	Customize templates, commands, and scripts	Preset management
Workflows	Automate repeatable, resumable processes	Workflow management
Bundles	Install a versioned setup of existing components	Bundle management