# Aontu

> Aontu is JSON plus a lattice. Two documents do not override each other, they unify: the result is the most specific value that satisfies both, or an error naming the contradiction. That makes a definition checkable, queryable and safe to change.

Documented against `aontu` 0.52.1. Every page below is also
served as markdown: append `.md`, or send `Accept: text/markdown` to the
page's own URL.

## Documentation

- [Aontu documentation](https://aontu.dev/docs.md): What Aontu is, how its documentation is organised, and a 30-second taste of unification.
- [Tutorial: your first unifications](https://aontu.dev/docs/tutorial.md): Learn Aontu from zero by building something, step by step — the learning-oriented path.
- [How-to guides](https://aontu.dev/docs/how-to.md): Recipes for tasks you already have in mind: validating in CI, gating schema changes, querying a definition.
- [Language reference](https://aontu.dev/docs/reference-language.md): The language, exhaustively: syntax, semantics, the unification lattice, and every operator.
- [API reference](https://aontu.dev/docs/reference-api.md): The API and the command line: eleven verbs, every flag, every exit code, and the MCP server.
- [Aontu Language Server (LSP)](https://aontu.dev/docs/lsp.md): The aontu-lsp language server — diagnostics, hover and completion, how to wire it into an editor, and the reusable library API.
- [Explanation: how and why Aontu works](https://aontu.dev/docs/explanation.md): How and why the engine works the way it does — the only part of the documentation that argues about trade-offs.
- [The Aontu trust contract](https://aontu.dev/docs/trust.md): The trust contract: hermeticity, termination, determinism and sandboxing — what a host may rely on, and exactly where each guarantee is conditional today.

## Beyond this site

- [Source](https://github.com/aontu-lang/aontu): both implementations, the shared test suite, and the design record.
- [Agent skill](https://github.com/aontu-lang/aontu/blob/main/docs/skill/SKILL.md): the teaching pack — grammar card, worked example ladder, error-code index.
- [Published grammar](https://github.com/aontu-lang/aontu/tree/main/grammar): GBNF and Lark, for constrained decoding.
- MCP: `npx -p aontu@0.52.1 aontu-mcp` — a local stdio server answering with the same reports the CLI prints.