SynthesisUI
For builders shipping with AI agents

Your agent ships UI all day. Nothing checks if it’s still yours.

SynthesisUI builds an AI-ready design system - tokens, typed components, motion, usage laws - and compiles it into a contract your coding agent obeys. Then it audits your repo and tells you how much of what shipped actually came from it.

Check your systemCreate your system

Free during launch - credits included, no card.

Runs on your repo, locally. Free, no account - the number it prints is the pitch.

  • audits any repo, free
  • token-only
  • portable to any agent

engine v0.9 · this page obeys the same laws it sells

The layer

Component libraries give you parts. Generators give you taste. Nobody makes the output keep the decisions.

A system is born from

  • Figmasoonread the file, keep the intent
  • shadcn/uiadopt the theme you already styled
  • any URLa system reborn from any site's craft
  • your existing appsoona skill reads what you built and births its system
  • an imagesoonfrom a screenshot or a moodboard
  • from scratchborn in the studio, governed from day one

And becomes the contract

  • The vocabularytokens, recipes and laws your agent reads before writing
  • The checkevery write measured on your machine, as it happens
  • The recordchecks become a ledger, refusals become requests, decisions become rules

Below it, Claude Code, Cursor or any agent ships UI all day - and the refusals travel back up as rules, so the system learns your boundaries instead of forgetting them. Nothing here competes with what you already use.

Token governance

Nothing closes on trust alone.

Checks become a local record. Refusals become requests. Your answers become deliveries or rules. Every step below is real output.

1 · The refusal files itself

agent: this system has no red. Filing the gap instead of inventing one.

Filed as a3f21c.

Do not add the token yourself - the request shows up for a person to decide.

The use case and the considered alternatives arrive already written - by the party that hit the gap.

2 · You answer on the dashboard

$ npx synthesisui sync

Answered on the platform, closed here:

✓ a3f21c authored. Get it: npx synthesisui upgrade

The dashboard never edits your files. Your own sync enacts every decision, out loud, on your machine.

3 · Or it becomes law

✕ declined - "this brand has no red; alerts use amber."

Now a RULE of the system - it travels with the next install, and agents obey it.

Rules are born from real cases, with the provoking request kept on record - jurisprudence, not brainstorms.

The whole cycle, spelled out: how governance works →

Shipped, not promised

Real pages, running on systems born here.

Not mockups and not screenshots: live sites you can open, inspect and audit. Each one installed a system from here into an empty project and let a coding agent build against its contract.

live · four of them

Forked from Halation · source open

Your moments, written in warm light.

Someone took Halation from the gallery, forked it into a system of their own and shipped this. Then left the repository public - so you do not have to believe the number below. Clone it and run the audit yourself.

See it live →npx synthesisui@latest doctor93%from tokens

Read the sourceThe system it forked

Vesper · in production

And one that is not a landing page.

A screener that reads 831 stocks and 307 REITs against eight public investment methods, every day. Tables, live prices, filters, an admin - the kind of surface a design system either survives or quietly falls apart on. It wears Vesper.

Open it →
831
stocks screened
307
REITs screened
103
--ds-* live on the page
8
methods applied daily

And two films from one custom system, Aluna

Supercreative prompt

The hero was always you.

8 acts · gsap · tokens only

Landing builder

A landing assembled like Lego.

visual builder · one prompt

every one: one npx init · one prompt · that's the whole trick

Integration

Three doors in. One folder. No lock-in.

No system yet

npx synthesisui init --ds <slug>

Pick one from the gallery or birth your own - it arrives as files you own: tokens, typed components, the GUIDE your agent reads first.

Already have a system

npx synthesisui adopt

Your tokens, described - not replaced. The doctor starts naming hand-written values in YOUR vocabulary the same afternoon.

On shadcn/ui

@import "_synthesisui/ds/<slug>/shadcn.css";

One line after your tokens import, and every shadcn component switches onto the system's clock and palette.

Everything lives in one folder, _synthesisui/, plus one hook. Leaving is deleting it - and the check that runs itself on every write is why you will not.

Built for Claude Code first · contract + doctor run anywhere

One product · six souls

The same screen, reborn in six design systems.

One layout, one accent color. Flip the personality and the whole thing changes character - shape, elevation, density, motion and type do the work. Every one is born excellent. Color is the small part.

Now showing
Editorial
serif · airy · calm
97Born excellentScored on the canon
Birth an Editorial system

Free, and no account needed.

EDITORIAL · serif · airy · calm
OverviewDeploysTeam
Workspace

Ship faster, everywhere.

Three edge regions from a single push. Rollbacks are one click.

47Deploys ↑12%
99.98%Uptime
3Regions
aurora-prodLive2m ago
aurora-stagingBuilding5m ago
docs-siteLive1h ago

Your design system is waiting to be born.

Two minutes from a blank canvas to a scored, documented system - ready for your agent, your repo and your next release.

Create your systemExplore the gallery
$npx synthesisui@latest init --styles tailwind --ds <slug>

Already have a design system? Point this at your repo instead - it reads your code locally and scores how much of your UI came from your own tokens. No account.

$ npx synthesisui@latest doctor

Not sure where to start? Follow a guided mission in the Cookbook →