doclang 0.5.0

DocLang reference validator

DocLang

DocLang is the AI-native markup format for unstructured content — including documents, images, and more. It maps cleanly to LLM tokens while preserving structure, semantics, layout, and geometry in a single, unambiguous representation.

This repository is the home of the normative specification and the reference validator for DocLang. If you build with LLMs and VLMs on real-world content, this is where the standard lives.

Specification

The source of the specification is available in spec.md and exports to different formats can be found in the exports/ directory.

Reference Validator

You can install the validator from PyPI:

pip install doclang

You can then validate a DocLang document as follows:

doclang validate -n my_document.dclg.xml

For more details, see the doclang/README.md.

Citation

If you use DocLang in academic or technical work, please cite the specification:

@misc{doclang_2026,
  title        = {DocLang: Universal AI Document Format},
  author       = {{DocLang Project}},
  year         = {2026},
  version      = {main},
  howpublished = {\url{https://github.com/doclang-project/doclang}},
}

Development

To work on this repository — setup, tests, reference generation, releases — see CONTRIBUTING.md.

We ❤️ Open Source AI

DocLang is developed in the open and supported by the LF AI & Data Foundation. Learn more about the project at doclang-project.

License

DocLang is licensed under the Apache License 2.0. See LICENSE for details.