Formhaus MCP server

Formhaus

Formhaus is a JSON form definition with a zero-dependency engine, React and Vue renderers, a Figma plugin, a JSON Schema and an MCP server for AI agents. One file describes fields, validation, conditional fields, multi-step navigation, branching routes and skippable steps.

Example · Packages · Install · Quick start · Custom components · Figma plugin · Docs · Spec · Playground

What it's for

• Multi-step forms with branching in React or Vue.
• Rendering a form from JSON with your own components.
• Designing the form in Figma from the same file.
• Generating and checking definitions with AI agents: Claude Code skills, the MCP server (claude plugin marketplace add ignsm/formhaus && claude plugin install formhaus@formhaus), the JSON Schema and the format specification.
• A headless engine for Svelte or vanilla JS.

Example

Business accounts get a company step; everyone converges on review.

{
  "$schema": "https://formhaus.dev/schema/form-definition.json",
  "id": "signup",
  "title": "Sign up",
  "submit": { "label": "Create account" },
  "steps": [
    {
      "id": "account",
      "title": "Account",
      "fields": [
        { "key": "email", "type": "email", "label": "Email", "validation": { "required": true } },
        { "key": "kind", "type": "radio", "label": "Account type", "autoAdvance": true,
          "options": [{ "value": "personal", "label": "Personal" }, { "value": "business", "label": "Business" }] }
      ],
      "routes": [
        { "to": "company", "show": [{ "field": "kind", "eq": "business" }] },
        { "to": "review" }
      ]
    },
    { "id": "company", "title": "Company", "routes": [{ "to": "review" }],
      "fields": [{ "key": "company", "type": "text", "label": "Company name", "validation": { "required": true } }] },
    { "id": "review", "title": "Review",
      "fields": [{ "key": "terms", "type": "checkbox", "label": "I accept the terms", "validation": { "required": true } }] }
  ]
}

import { FormRenderer } from '@formhaus/react';
import definition from './signup.json';

<FormRenderer definition={definition} onSubmit={save} />;

Compare with react-hook-form, TanStack Form, react-jsonschema-form and SurveyJS →

Packages

Shortened. The full README is on GitHub.