Spec-driven AI development

Spec-driven development for developers.

Spec4 AI works with you as a partner and advisor to guide you through a pipeline of six specialized AI agents that turn a rough idea — or an existing codebase — into a complete, phase-by-phase implementation spec, UI mock, and deployment plan ready for your agentic coding tool and infra.
It's way more powerful than /plan.

Get Started → See How It Works

"You've made something really really really cool. I'm almost done with our driver app. Will be field tested by Friday. I don't think I would have built what this is going to become without it."
— Wihan Booyse, Kriterion.ai

The Pipeline

See how it works.

🔍 CodeScanner → 🧠 Brainstormer → 🎨 Designer → ⚙️ StackAdvisor → 📋 Phaser → 🚀 Deployer

Walk through each step of the Spec4 pipeline. Learn how CodeScanner reads your codebase, how Brainstormer defines your vision, how Designer mocks your UI, how StackAdvisor recommends your tech stack, how Phaser breaks it into executable phases, and how Deployer plans your path to production.

See the full pipeline →

The Problem

Great ideas deserve great specs.

Agentic coding tools like Claude Code, Codex, Antigravity, and Hermes have transformed how developers write software. But they can only be as good as the plan they're given. A vague or incomplete prompt leads to a vague or incomplete result — and an expensive amount of back-and-forth.

Spec4 bridges the gap between "I have an idea" and "I have a production-ready implementation plan." It structures your thinking, fills the gaps you didn't know existed, and produces machine-readable specs that agentic coders can execute reliably — phase by phase.

How It Works

A pipeline built for the way developers actually work.

🔍 CodeScanner → 🧠 Brainstormer → 🎨 Designer → ⚙️ StackAdvisor → 📋 Phaser → 🚀 Deployer

01 🔍 CodeScanner (optional)

Reads your existing codebase so nothing gets lost in the transition to what's next.

code_review.json

02 🧠 Brainstormer

Collaborates with you to define a clear, complete vision — no gaps, no ambiguity.

vision.json

03 🎨 Designer (optional)

Generates a self-contained HTML mock of your UI so you have a visual target before a line of code is written.

mock.html

04 ⚙️ StackAdvisor

Guides you through selecting a technology stack that fits the vision and your requirements.

stack.json

05 📋 Phaser

Breaks the build into executable phases designed for first-attempt success.

phases.zip

06 🚀 Deployer

Plans your path to production — coding agent guidance, infrastructure, CI/CD, and monitoring.

deployment-plan.md

See the full pipeline

See It in Action

From one paragraph to a production plan.

Here's how Spec4 handled a real project brief:

project brief

> "I'd like to create an application to help healthcare professionals in regions where limited resources are available to be as efficient as possible — providing knowledge, advice, and helping to streamline processes and paperwork."

From this single paragraph, Spec4's pipeline clarified the target users, identified missing decisions (offline capability? local language support? integration with existing records systems?), recommended a technology stack, and produced a phased implementation plan — all ready to hand directly to an agentic coding tool.

Walk through the example

Stop prompting. Start speccing.

Spec4 is free to use. Bring your own AI provider and model.

Get Started → How It Works