# About agentmarkup - who builds it and why

> agentmarkup is open-source, MIT-licensed build-time tooling for machine-readable websites, built and maintained by Sebastian Cochinescu at Anima Felix. What it does, what it deliberately does not do, and what ships today.

Source: https://agentmarkup.dev/about/

About

# About agentmarkup

agentmarkup is an open-source, MIT-licensed toolkit that makes a website machine-readable at build time. It generates llms.txt, injects JSON-LD structured data, can produce markdown mirrors of final HTML, manages AI crawler directives in robots.txt, emits Content-Signal headers, and validates all of it before the build finishes. It is built and maintained by Sebastian Cochinescu at Anima Felix.

## Why it exists

Anima Felix had the same problem most sites have. ChatGPT and Claude could find the site, but they could not really understand it. The pages were a client-rendered shell, the structured data was incomplete, there was no llms.txt, and nothing in the build caught any of that. Every fix was manual, and every fix drifted the next time the site changed.

So the fixes were moved into the build. That internal tooling became agentmarkup, and it was open sourced because the problem is not specific to one site. If the machine-readable layer of a website is not generated and validated by the build, it goes stale the moment someone ships a redesign.

## What it is, and what it is not

agentmarkup is a build-time dependency you install from npm. There is no SaaS, no account, no runtime service, and nothing phones home. It runs inside your build, writes files into your output directory, and gets out of the way.

It is also deliberately not a scoring tool. Validation is deterministic: a missing required field is an error, a missing recommended field is a warning, and there are no readiness scores, letter grades, or percentages anywhere in the output. A number that nobody can reproduce is not a finding, and the field is already full of them.

## What ships today

The published package family covers the frameworks that own enough of their final build output to make a build-time pass meaningful:

- [@agentmarkup/vite](https://www.npmjs.com/package/@agentmarkup/vite), [@agentmarkup/astro](https://www.npmjs.com/package/@agentmarkup/astro), [@agentmarkup/next](https://www.npmjs.com/package/@agentmarkup/next) and [@agentmarkup/nuxt](https://www.npmjs.com/package/@agentmarkup/nuxt) are the framework adapters.
- [@agentmarkup/cli](https://www.npmjs.com/package/@agentmarkup/cli) runs the same pipeline over any built static output and gates a CI job.
- [@agentmarkup/audit](https://www.npmjs.com/package/@agentmarkup/audit) fetches a live URL as each major AI crawler and diffs the result against a browser fetch.
- [@agentmarkup/core](https://www.npmjs.com/package/@agentmarkup/core) exposes the generators and validators for custom prerender pipelines.

This website is built with agentmarkup. Its llms.txt, JSON-LD, markdown mirrors, robots.txt crawler rules and Content-Signal headers are all generated by the same packages you would install.

## Who maintains it

[Sebastian Cochinescu](/authors/sebastian-cochinescu/) maintains agentmarkup at [Anima Felix](https://animafelix.com), where it runs in production. Maintenance is handled by one person, so support is best effort. The [source code](https://github.com/agentmarkup/agentmarkup) is public, the [license is MIT](/license/), and contributions go through GitHub. For anything else, see [Contact](/contact/).