Essentials

LLM resources for agents

Updated: Sep 1, 2026

Meta publishes its Horizon OS developer documentation in a form built for large language models (LLMs). Point an AI tool at it and you get current, accurate answers about Meta VR development.

LLM-optimized documentation

These pages are plain text. They carry no navigation, no ads, and none of the other page furniture that lowers an answer’s accuracy.

Documentation index pages

Each build path has an index of all its pages. Some also have an API reference index:

Unity:

Unreal:

Spatial SDK:

Android Apps:

Android Apps documentation index

Native:

Native documentation index

Web:

Web documentation index

Note: The API reference indices use latest where it is available. Spatial SDK does not provide a latest alias, so its API reference index is pinned to a released version.

Additional indices

Accessing LLM resources

Through Meta VR CLI

Meta VR CLI can search this documentation and fetch a page in full, both from the command line and through its MCP server.

Ask your AI assistant a Meta VR question and it finds the right pages and reads them. You do not supply a URL. Your agent learns what it can do when it connects, so it tracks the version of the CLI you have.

From a terminal, the same search is metavr docs search "<your topic>".

Direct access

You can also point any AI tool straight at these URLs. Each one returns Markdown.

API reference pages

Most SDKs have Markdown API reference pages, for recent versions. Not every SDK or version has one. Index pages follow this URL pattern:

https://developers.meta.com/horizon/reference/{sdk}/{version}/index.md

Set {sdk} to the SDK name, such as unity, unreal, or spatial-sdk. Set {version} to a released version, or to latest where it exists. For example:

Unity SDK API reference index:

https://developers.meta.com/horizon/reference/unity/latest/index.md

Spatial SDK API reference index:

https://developers.meta.com/horizon/reference/spatial-sdk/v0.13.1/index.md

To get the Markdown for a single API reference page, add .md to its URL:

https://developers.meta.com/horizon/reference/{sdk}/{version}/{page}.md

For example, the Unity AlertViewHUD class reference:

https://developers.meta.com/horizon/reference/unity/v203/class_alert_view_h_u_d.md

If a URL says the content is not available, that SDK version has no Markdown reference. Try a newer released version.

Documentation pages

The base URL pattern is:

https://developers.meta.com/horizon/llmstxt/documentation/{platform}/{page-slug}.md/

Set {platform} to your build path: unity, unreal, spatial-sdk, android-apps, native, or web. Set {page-slug} to the page name. To find page names, start from the documentation index for your platform.