<!-- SPDX-License-Identifier: CC-BY-SA-4.0 -->
<!-- SPDX-FileCopyrightText: 2025-2026 Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk> -->
---
title: A2ML specification
site: A2ML
brand: A2ML
description: The normative A2ML v1.1.0 specification — surface grammar, typed core, profiles, and conformance test vectors.
date: 2026-06-29
---

# Specification

The current normative specification is **A2ML v1.1.0** — Surface Grammar + Typed Core + Profiles.

## Documents

- **Spec (normative, v1.1.0)** — surface grammar, typed core, profiles
- **Specification lineage** — versions and era
- **Module 0 quickstart + FAQ**
- **Syntax modules** (opt-in)
- **Grammar appendix**
- **Conformance + test vectors**
- **IANA media type draft** — `application/vnd.a2ml`
- **Comparison matrix**
- **Citation guide**

All specification documents are maintained in the [standards](https://github.com/hyperpolymath/standards) repository under `a2ml/`. This page links the front door; the repository is the source of truth.

## Profiles

Profiles layer domain-specific validation on top of the base vocabulary. A2ML v1.1 introduced profiles, an expanded base vocabulary, citation support and content hashing.

## Conformance

Conformance is defined by published test vectors (positive and negative fixtures). Implementations validate against these to claim a given strictness level.
