Open Vet Format (OVF)

A FHIR-inspired JSON Schema standard for veterinary medical record exchange.

The veterinary market — especially in Poland and Central Europe — has no standard for exchanging medical records between clinics, pet owners, and software systems. OVF fills this gap with a pragmatic, JSON-based format designed specifically for veterinary medicine.

Quick Example

A minimal valid OVF document:

{
  "format_version": "1.0.0",
  "exported_at": "2026-03-30T12:00:00Z",
  "exporter": {
    "name": "VetNote",
    "version": "2.0.0"
  },
  "patient": {
    "resource_type": "Patient",
    "id": "550e8400-e29b-41d4-a716-446655440000",
    "name": "Luna",
    "species": "dog",
    "breed": "Golden Retriever",
    "date_of_birth": "2023-06-15",
    "sex": "female",
    "gender_status": "spayed",
    "identifiers": [
      {
        "system": "iso-microchip-11784",
        "value": "616093900012345"
      }
    ]
  }
}

Why Not Just Use FHIR?

HL7 FHIR is the gold standard for human healthcare interoperability. But it's a poor fit for veterinary MVPs:

| Concern | FHIR | OVF | |---------|------|-----| | Complexity | 150+ resource types, deep nesting | 10 resource types, flat structure | | Format | XML + JSON, heavy tooling | JSON only, any language | | Veterinary support | Minimal — adapted from human medicine | Purpose-built for vet clinics | | Adoption in vet market | Near zero | Growing (designed for it) | | Getting started | Weeks of reading specs | 5 minutes |

OVF maps cleanly to FHIR concepts (see FHIR Mapping), so migration to full FHIR is possible when the market matures.

Why Not VetXML?

VetXML was a UK-led initiative that never gained adoption outside a handful of UK practice management systems. It's XML-based, poorly documented, and effectively abandoned.

Resource Types

| Resource | Description | |----------|-------------| | Patient | Pet with species, breed, microchip, EU passport | | Practitioner | Veterinary professional (referenced by clinical resources) | | Encounter | Veterinary visit or consultation | | Condition | Diagnosis (active, resolved, chronic) | | Observation | Lab results, vital signs, clinical notes | | Immunization | Vaccinations with batch, expiry, next dose | | Procedure | Surgeries, dental work, grooming | | AllergyIntolerance | Food, medication, environment allergies | | MedicationStatement | Prescribed and active medications | | DocumentReference | Scanned documents, lab report files |

Installation

Schemas + CLI validator

npm install @vetformat/ovf

Typed SDKs

# TypeScript
npm install @vetformat/ovf-types

# Python
pip install ovf-types

Validate a document

npx ovf-validate ./my-record.json

Programmatic usage (TypeScript)

import type { OvfDocument, Patient, Practitioner } from "@vetformat/ovf-types";

const doc: OvfDocument = {
  format_version: "1.2.0",
  exported_at: new Date().toISOString(),
  patient: { resource_type: "Patient", id: "p-001", name: "Luna", species: "dog" },
  practitioners: [
    { resource_type: "Practitioner", id: "pract-001", name: "Dr. Anna Nowak" }
  ],
};

Programmatic usage (Python)

from ovf_types import OvfDocument, Patient, Practitioner

doc = OvfDocument(
    format_version="1.2.0",
    exported_at="2026-03-30T12:00:00Z",
    patient=Patient(resource_type="Patient", id="p-001", name="Luna", species="dog"),
    practitioners=[
        Practitioner(resource_type="Practitioner", id="pract-001", name="Dr. Anna Nowak")
    ],
)

Schema validation (programmatic)

import Ajv from "ajv";
import addFormats from "ajv-formats";
import schema from "@vetformat/ovf/schemas/v1/ovf.schema.json";

const ajv = new Ajv({ allErrors: true });
addFormats(ajv);
const validate = ajv.compile(schema);

const valid = validate(myDocument);
if (!valid) console.error(validate.errors);

Polish Extensions

OVF includes first-class support for the Polish veterinary market:

• Microchip registries: SAFE-ANIMAL, EUROPETNET
• EU Pet Passport identifier system
• FCI breed codes for pedigree dogs
• ISO 11784/11785 microchip format

See Polish Extensions for details.

Documentation

• Specification — formal spec with RFC 2119 language
• Getting Started — 5-minute quickstart
• FHIR Mapping — how OVF maps to FHIR resources
• Polish Extensions — Poland-specific fields
• Examples — real-world example documents

Adopters

See ADOPTERS.md for organizations using OVF.

Contributing

We welcome contributions! See CONTRIBUTING.md for guidelines.

Schema changes follow an RFC process: open an issue using the Schema Change template, discuss for 14 days, then submit a PR.

License

• Schemas and code: Apache License 2.0
• Documentation (docs/ directory): CC-BY-4.0

This dual-licensing ensures schemas can be freely used in commercial products while documentation attribution is maintained.

AI / LLM Integration

This repository is AI-friendly by design:

• Every schema field has description and examples
• llms.txt provides a structured project summary
• llms-full.txt provides full context for LLM consumption
• Schemas are self-documenting — an LLM can generate valid OVF documents from the schemas alone