Decantr MCP Server

Design intelligence, governance, and verification for AI-generated UI.

Decantr is the contract layer between product intent and AI-generated implementation. It gives coding assistants three things they don't have on their own — structured design inputs, registry-backed UI knowledge, and scoped context files — so they build coherent product surfaces instead of improvising screen by screen. Think of it as OpenAPI for AI-generated UI: the model still writes the code, but Decantr defines the shape, vocabulary, and checks around it.

AI generates the interface. Decantr keeps the outcome aligned.

Pick your path

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Greenfield blueprint

1. Scaffold from a blueprint

npx @decantr/cli new my-app --blueprint=agent-marketplace
cd my-app

A blueprint is a published app composition — theme, sections, pages, layouts, voice, and personality. Try agent-marketplace, terminal-dashboard, or portfolio to start, or run decantr search to browse the full catalog.

Adapter availability. react-vite and next-app are runnable starter adapters in this wave. Other contract targets remain valid Decantr targets but initialize through generic-web contract-only mode — Decantr writes the contract, you own the runtime.

2. What just got generated

my-app/
├── decantr.essence.json     # the durable contract: theme, sections, routes, features
├── DECANTR.md               # methodology primer your AI assistant reads first
├── .decantr/context/
│   ├── scaffold.md          # full app overview: topology, voice, personality
│   └── section-*.md         # per-section spec: shell, patterns, spacing
└── src/styles/
    ├── tokens.css           # CSS variables from the theme
    ├── treatments.css       # shared visual treatment classes
    └── decorators.css       # theme-specific decorator classes

Decantr produces the contract. Your AI assistant produces the implementation against it.

3. Hand it to your AI assistant

Open the project in Claude Code, Cursor, Windsurf, or any AI-aware editor. Your assistant reads DECANTR.md first for the methodology, then loads section context files on demand as it works through each part of the app. The split keeps the assistant focused on the right scope at the right time.

4. Make your first change and verify

# Edit decantr.essence.json — add a section, swap the theme, etc.
decantr refresh   # regenerate context files from the updated essence
decantr check     # verify the code matches the new contract
decantr health    # produce a local project health report for triage or CI
decantr studio    # open the local-only health dashboard

refresh keeps the generated context files in sync with the essence. check runs the guard rules and tells you exactly where the code drifted from the contract. decantr health is the end-user observability surface: it combines audits, checks, route drift, runtime evidence, and pack health into a structured report, while decantr studio gives the same signal in a small localhost dashboard. decantr audit remains the lower-level audit pass when you want verifier evidence directly.

Starting from a different point? See the full workflow model.

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The model

Decantr separates design governance into two layers:

• DNA — durable visual and system axioms: theme, spacing, motion, accessibility, personality.
• Blueprint — product topology: sections, page routes, shells, layouts, features.

That split matters because not every change should be treated the same way. A theme swap or accessibility regression is different from adding an auxiliary section or reshaping a route map. Decantr lets governance be strict where it should be strict (DNA, errors by default) and flexible where it should be flexible (Blueprint, warnings only).

Canonical shapes live in the published schemas; the command-level flow is in the workflow model.

Surfaces

Packages

Full release/support status lives in docs/reference/package-support-matrix.md.

Repo layout

Showcase capsule architecture is documented in docs/reference/showcase-host.md.

Development

Requires Node.js >=20 and pnpm >=9.

pnpm install
pnpm build
pnpm test
pnpm lint
pnpm audit:public-api
pnpm audit:registry-dogfood
pnpm showcase:verify:shortlist
pnpm release:verify

More CLI

Intent and discovery:

decantr magic "AI chatbot with a bold terminal-inspired workspace"
decantr search dashboard
decantr suggest leaderboard

Brownfield adoption:

decantr analyze
decantr init --existing --accept-proposal
decantr check --brownfield
decantr health

Registry and verification:

decantr registry summary       --namespace @official --json
decantr registry compile-packs decantr.essence.json --write-context
decantr registry critique-file src/pages/Home.tsx  --namespace @official --json
decantr registry audit-project --namespace @official --json
decantr showcase verification  --json

Project Health and CI:

decantr health --format markdown
decantr health --ci --fail-on error
decantr health --prompt <finding-id>
decantr health init-ci
decantr health init-ci --project apps/registry
decantr health --json --output decantr-health.json
decantr studio --port 4319 --host 127.0.0.1
decantr studio --report decantr-health.json

Opted-in product telemetry:

decantr telemetry status
decantr telemetry explain
decantr telemetry link --enable --org <org-slug>

Telemetry stays product-level: command names, aggregate lifecycle counts, registry sources, Project Health scores/counts, private-registry readiness, and billing intent. decantr telemetry explain prints the CLI event catalog subset and never-collected list before a team opts in. It does not collect source code, prompts, raw paths, emails, private package slugs, or health report contents.

Official content supply chain:

decantr content-health
decantr content-health --markdown --output content-health.md
decantr content-health --ci --fail-on error
decantr content-health --prompt <finding-id>

FAQ

How does Decantr keep AI or agent work tied back to the original spec?

You cannot truly force an LLM to follow a spec. Decantr gives the assistant a durable contract, scoped context, and drift checks so implementation stays tied to the intended product shape.

decantr refresh
decantr check
decantr audit
decantr health

If the product direction changes, update Decantr deliberately, then regenerate and check:

decantr add page dashboard/reports
decantr refresh
decantr check

How do I open Decantr Studio?

Run Studio from the app root, where decantr.essence.json lives:

decantr studio

If the default port is busy:

decantr studio --host 127.0.0.1 --port 4320

Studio is local-only and shows the same Project Health signal as decantr health. Its Overview keeps triage focused: pick the issue to fix first, review the AI prompt before copying it, switch to manual guidance or commands, and expand project details when you need route/runtime/pack evidence.

decantr health --prompt <finding-id> prints a focused repair prompt for the assistant doing the implementation. It does not edit files by itself; use Studio's copy buttons or paste the printed prompt into your AI coding workflow, then rerun Project Health.

To view a CI-produced report artifact without scanning a checkout:

decantr health --json --output decantr-health.json
decantr studio --report decantr-health.json

Studio is for interactive triage; decantr health --ci --fail-on error is still the pull-request gate.

See the full FAQ for common setup, brownfield, Studio, migration, CI, and drift questions.

Links

• Registry — registry.decantr.ai
• Discord — discord.gg/WeDpBd4xFU
• FAQ — docs/faq.md
• Published schemas — decantr.ai/schemas
• Project Health — docs/reference/project-health.md
• Content Health — docs/reference/content-health.md
• Workflow model — docs/reference/workflow-model.md
• Public API reference — docs/reference/registry-public-api.md
• Package support matrix — docs/reference/package-support-matrix.md

Contributing

Contributions are welcome. The most useful repo context lives in docs/ — especially the architecture notes, audits, runbooks, and package support matrix.

Use Discord for quick setup help, showcase feedback, and live community discussion. Keep bugs, feature requests, and durable decisions in GitHub issues, PRs, or docs.

License

MIT. The source repositories are MIT licensed; hosted services such as the registry and API may publish separate service terms without changing the source-code license.