sphinx-llm¶

Make your docs readable by AI assistants and coding tools. sphinx-llm generates LLM-friendly versions of your documentation following the llms.txt convention — Lumina links to llms.txt automatically once the extension is enabled.

2 min read

What It Produces¶

llms.txt — A markdown index of all pages with titles, URLs, and descriptions, plus a scoped llms.txt in each section folder
llms-full.txt — The full content of every page concatenated into a single markdown file (opt-in, see llms_txt_full_build)
Per-page .md files — Each HTML page gets a companion markdown file (e.g., getting-started.html.md and getting-started.md)

Lumina Integration¶

Lumina automatically adds a <link rel="alternate"> tag in the HTML <head> pointing to llms.txt when this extension is detected — no extra configuration needed. sphinx-llm 1.1 and later also add their own <link rel="describedby"> tag.

Setup¶

uv add sphinx-llm

conf.py¶

extensions = ["sphinx_llm.txt"]

That’s it. On the next build, llms.txt and per-page .md files appear alongside your HTML output.

Lumina’s own documentation builds with -W and also sets these options:

conf.py¶

llms_txt_full_build = True
# Skip nodes the Markdown export can't render (tips, sidebars, diagrams)
# instead of warning about each one.
llms_txt_suppress_unknown_node_warnings = True

Configuration¶

All options are optional — the defaults work well for most projects:

Option	Default	Description
`llms_txt_enabled`	`True`	Master on/off switch. Disable with `llms_txt_enabled = False`.
`llms_txt_description`	Auto-detected	Project description shown in the `llms.txt` header. Falls back to `pyproject.toml` description, then `html_title`.
`llms_txt_build_parallel`	`True`	Run the markdown build in parallel with the HTML build.
`llms_txt_suffix_mode`	`"auto"`	Controls per-page markdown filenames: `"append"` writes `page.html.md`, `"replace"` writes `page.md`, and `"auto"` writes both. `"file-suffix"` and `"url-suffix"` are deprecated aliases for `"append"`.
`llms_txt_full_build`	`False`	Whether to generate `llms-full.txt`. Before sphinx-llm 1.1 this defaulted to `True`.
`llms_txt_exclude`	`[]`	Glob patterns of document names (e.g. `"internal/*"`) to leave out of the `llms.txt` outputs.
`llms_txt_suppress_unknown_node_warnings`	`False`	Skip document nodes the Markdown export can’t render without warning. `True` silences all of them; a list of node class names silences only those.

How It Works¶

The extension runs a parallel Sphinx build using a markdown builder. All directives (including autodoc, toctree, cross-references) are fully expanded in the output — you get clean, rendered markdown, not raw source.

Each entry in llms.txt includes a description sourced from the page’s meta description or the first 100 characters of content.