OpenForm is documents as code. It lets developers and AI agents define, validate, and render business documents using typed, composable schemas. This eliminates template drift, broken mappings, and brittle glue code — while giving AI systems a reliable document layer they can safely read, reason over, and generate against in production workflows.

Package overview

Fundamental package for modeling business documents as typed, versioned artifacts. Provides builders for Forms, Documents, Checklists, and Bundles with schema-driven validation and composition.

• 🏗️ Type-safe builders - Fluent API for defining document structures
• 📋 Four artifact types - Form, Document, Checklist, and Bundle builders
• ✅ Schema-driven validation - Built-in structure and constraint validation
• 🎯 Composable design - Reuse fields and artifacts across definitions
• 📦 Standalone library - Use independently or with @open-form/sdk

Installation

npm install @open-form/core

Usage

Define forms with parties, fields, and validation rules:

import { open } from "@open-form/core";

const leaseAgreement = open
  .form()
  .name("residential-lease-agreement")
  .version("1.0.0")
  .title("Residential Lease Agreement")
  .defaultLayer("markdown")
  .layers({
    markdown: open
      .layer()
      .file()
      .mimeType("text/markdown")
      .path("fixtures/lease-agreement.md"),
  })
  .parties({
    landlord: open
      .party()
      .label("Landlord")
      .signature((sig) => sig.required()),
    tenant: open
      .party()
      .label("Tenant")
      .multiple(true)
      .min(1)
      .max(4)
      .signature((sig) => sig.required()),
  })
  .fields({
    leaseId: { type: "uuid", label: "Lease ID" },
    propertyAddress: {
      type: "address",
      label: "Property Address",
      required: true,
    },
    monthlyRent: { type: "money", label: "Monthly Rent", required: true },
    leaseStartDate: { type: "date", label: "Lease Start Date", required: true },
  })
  .build();

Add file attachments and advanced field types:

const advancedLease = open
  .form()
  .name("commercial-lease")
  .version("1.0.0")
  .title("Commercial Lease Agreement")
  .allowAnnexes(true)
  .annexes([
    open.annex().id("photoId").title("Photo ID").required(true),
    open.annex().id("proofOfIncome").title("Proof of Income").required(true),
  ])
  .parties({
    landlord: open
      .party()
      .label("Landlord")
      .signature((sig) => sig.required()),
    tenant: open
      .party()
      .label("Tenant")
      .multiple(true)
      .signature((sig) => sig.required()),
  })
  .fields({
    leaseId: { type: "uuid", label: "Lease ID", required: true },
    leaseTermMonths: {
      type: "number",
      label: "Lease Term (months)",
      required: true,
    },
    monthlyRent: { type: "money", label: "Monthly Rent", required: true },
    petPolicy: {
      type: "enum",
      enum: ["no-pets", "small-pets", "all-pets"],
      label: "Pet Policy",
      required: true,
    },
  })
  .build();

Define static documents with metadata:

const leadPaintDisclosure = open
  .document()
  .name("lead-paint-disclosure")
  .version("1.0.0")
  .title("Lead Paint Disclosure")
  .code("EPA-747-K-12-001")
  .releaseDate("2025-12-01")
  .metadata({ agency: "EPA/HUD", cfr: "40 CFR 745" })
  .layers({
    pdf: open
      .layer()
      .file()
      .path("fixtures/lead-paint-disclosure.pdf")
      .mimeType("application/pdf"),
  })
  .defaultLayer("pdf")
  .build();

Define workflow checklists with status tracking:

const leaseChecklist = open
  .checklist()
  .name("lease-application-checklist")
  .version("1.0.0")
  .title("Lease Application Checklist")
  .items([
    {
      id: "application_received",
      title: "Application Received",
      status: { kind: "boolean" },
    },
    {
      id: "credit_check",
      title: "Credit Check Complete",
      status: { kind: "boolean" },
    },
    {
      id: "background_check",
      title: "Background Check Complete",
      status: { kind: "boolean" },
    },
    { id: "lease_signed", title: "Lease Signed", status: { kind: "boolean" } },
  ])
  .build();

Compose artifacts into bundles:

const propertyAddress = {
  type: "address",
  label: "Property Address",
  required: true,
};
const monthlyRent = { type: "money", label: "Monthly Rent", required: true };

const residentialLease = open
  .form()
  .name("residential-lease")
  .version("1.0.0")
  .fields({ leaseId: { type: "uuid" }, propertyAddress, monthlyRent })
  .build();

const commercialLease = open
  .form()
  .name("commercial-lease")
  .version("1.0.0")
  .fields({ leaseId: { type: "uuid" }, propertyAddress, monthlyRent })
  .build();

const leaseBundle = open
  .bundle()
  .name("residential-lease-bundle")
  .version("1.0.0")
  .contents([
    { type: "inline", key: "residential", artifact: residentialLease.schema },
    { type: "inline", key: "commercial", artifact: commercialLease.schema },
    { type: "inline", key: "disclosure", artifact: leadPaintDisclosure.schema },
    { type: "inline", key: "checklist", artifact: leaseChecklist.schema },
  ])
  .build();

Extract TypeScript types from artifacts:

import { type InferFormData } from "@open-form/core";

type LeaseData = InferFormData<typeof leaseAgreement>;

const data: LeaseData = {
  leaseId: "550e8400-e29b-41d4-a716-446655440000",
  propertyAddress: {
    line1: "123 Main St",
    locality: "Portland",
    region: "OR",
    postalCode: "97201",
    country: "USA",
  },
  monthlyRent: { amount: 1500, currency: "USD" },
  leaseStartDate: new Date("2024-02-01"),
};

Validate data against form schemas:

if (!leaseAgreement.isValid(data)) {
  console.log("Data does not match form schema");
}

try {
  const filled = leaseAgreement.fill(data);
} catch (error) {
  console.error("Validation failed:", error);
}

For rendering artifacts to PDF, DOCX, HTML, or other formats, use @open-form/sdk with the renderers package. For complete production examples, see /incubator/apps/demo/src/demos/leasing. For API reference and advanced patterns, visit docs.open-form.dev.

Changelog

View the Changelog for updates.

Related packages

• @open-form/sdk - Complete framework with renderers
• @open-form/types - TypeScript utilities and types
• @open-form/schemas - JSON Schema definitions
• @open-form/renderers - All renderers (PDF, DOCX, Text)
• @open-form/resolvers - File and environment resolvers

Contributing

We're open to all community contributions! If you'd like to contribute in any way, please read our contribution guidelines and code of conduct.

License

This project is licensed under the MIT license.

See LICENSE for more information.