geo-llmstxt

geo-llmstxt is a skill for Claude Code from techhorizonlabs/thl-open. It costs 46 tokens per session (1,415 once invoked), scanned A, original, MIT.

A tool for checking or creating an llms.txt file, a proposed website file that explains the site's purpose, structure, and most useful pages to AI systems.

In plain words
What is it for?
Use it to validate an existing llms.txt file or generate one by crawling a website.
Why use it?
It gives AI systems a direct summary instead of making them infer the site's organization by crawling many pages.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the thl-open plugin — 17 skills shipped together

Good fit Use it to validate an existing llms.txt file or generate one by crawling a website.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/techhorizonlabs/thl-open/geo-llmstxt
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add techhorizonlabs/thl-open --skill geo-llmstxt
Clone the repo
git clone --depth 1 https://github.com/techhorizonlabs/thl-open

Made for: Claude Code.

Or install thl-open, the plugin that ships this one along with the rest of its 17 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for geo-llmstxt

README.md
[![agentmods](https://agentmods.dev/badge/skills/techhorizonlabs/thl-open/geo-llmstxt/github.svg)](https://agentmods.dev/skills/techhorizonlabs/thl-open/geo-llmstxt)
Your own site
<a href="https://agentmods.dev/skills/techhorizonlabs/thl-open/geo-llmstxt"><img src="https://agentmods.dev/badge/skills/techhorizonlabs/thl-open/geo-llmstxt/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for geo-llmstxt

Your own site · 80×15
<a href="https://agentmods.dev/skills/techhorizonlabs/thl-open/geo-llmstxt"><img src="https://agentmods.dev/badge/skills/techhorizonlabs/thl-open/geo-llmstxt.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 46 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,415 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00046 $0.01415
Opus 5 $0.00023 $0.00707
Sonnet 5 $0.00009 $0.00283
Haiku 4.5 $0.00005 $0.00142

Measured 10d ago against content hash 5db1ebb855a3, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

geo-llmstxt scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/geo-llmstxt/SKILL.md · 112 lines

How it starts

The opening of the file, as written. The whole thing — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.

llms.txt Standard Analysis and Generation Skill

Purpose

This skill handles everything related to the llms.txt standard — an emerging convention (proposed by Jeremy Howard in September 2024) that lets a website give AI systems structured guidance about its content, structure, and key information. It is analogous to robots.txt (which tells crawlers what NOT to access) but instead tells AI systems what IS most useful to understand about the site.

The full format spec, the llms-full.txt variant, a fill-in template, and best practices live in references/spec.md — read it before validating or generating a file.

Why llms.txt Matters

AI models must work out which pages matter, what a site is about, and how content is organized — usually by crawling many pages and inferring structure. llms.txt solves this with an explicit, machine- and human-readable summary.

  1. Faster AI comprehension: understand the site's purpose and structure from one file rather than dozens of pages.
  2. Controlled narrative: you choose which pages and facts AI systems see first, shaping how they represent your brand.
  3. Higher citation accuracy: AI systems that consult llms.txt cite the correct, authoritative page for each topic.
  4. Reduced misrepresentation: key facts (pricing, features, locations) are stated explicitly, reducing hallucination.
  5. Early-adopter advantage: only a small minority of sites have an llms.txt today, so it remains a differentiator.

Analysis Mode

When checking an existing llms.txt file.

Step 1: Fetch the File

  1. Use WebFetch to retrieve [domain]/llms.txt. Also check [domain]/llms-full.txt.
  2. Record HTTP status: 200 → validate; 404 → recommend generation; 403 → file blocked, flag as misconfiguration; 301/302 → follow and note the redirect.

Step 2: Validate Format

Check each structural element against the format rules in references/spec.md:

Element Check Severity if Missing
H1 Title Present, matches business name Critical
Blockquote description Present, under 200 chars, factual High
At least one H2 section Present Critical
Page entries with URLs At least 5 entries present High
URLs are absolute All URLs use full https:// paths High
URLs are valid All URLs return 200 status Medium
Descriptions present Every entry has a description after the colon Medium
Key Facts section Present with business information Medium
Contact section Present with at least email Low
Reasonable length 30-200 lines Low
No broken Markdown Proper formatting throughout Medium

Read the full file on GitHub · 112 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 10d ago First seen · 112 lines · 46 tokens per session scan A 5db1ebb855a3

Subscribe to this mod's changes

geo-llmstxt is a skill published in the GitHub repository techhorizonlabs/thl-open (15 stars, last pushed yesterday), licensed MIT. It adds 46 tokens to every session and 1,415 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories

geo-visibility

Get cited and recommended by AI engines (ChatGPT, AI Overviews and AI Mode, Perplexity, Claude, Gemini). Input: a page or piece of content. Output: passage-level citability fixes (answer-first H2 blocks, self-contained chunks, definitions, sourced stats, comparison tables), a 5-pillar GEO score (0-100), an AI-crawler…

Thibaultbm/claude-seo-geo · 133 tokens

seo-content-blog

Write blog articles that rank on Google and get cited by AI engines (ChatGPT, Perplexity, AI Overviews). Input: a keyword, topic, or existing draft. Output: a publish-ready article, outline, or brief built on a 12-element answer-first skeleton (question H2s, expert quotes, stats, FAQ, internal links, SERP-benchmarked…

Thibaultbm/claude-seo-geo · 110 tokens

seo-content-collection-page

Optimize e-commerce collection, category, and product listing pages (PLPs) for Google and AI assistants. Input: a collection or category page (Shopify, WooCommerce, Magento, BigCommerce, PrestaShop, or custom). Output: a bottom-of-page SEO text block, faceted-navigation and filter URL control, pagination canonicals…

Thibaultbm/claude-seo-geo · 122 tokens

seo-content-product-page

Optimize e-commerce product pages (PDPs) for Google and for AI assistants that now recommend products directly. Input: a product page or description (Shopify, WooCommerce, Magento, BigCommerce, PrestaShop, Wix, Webflow, or custom). Output: a rewritten PDP with unique copy, FAQ and definition blocks, review and…

Thibaultbm/claude-seo-geo · 124 tokens

geo-tracking

Measure AI visibility without paid tools or API keys. Input: your site (GA4 and server logs) and a buyer prompt panel. Output: GA4 AI-traffic reporting (custom channel group plus referrer regex above Referral), monthly brand mention rate, citation rate, and share of voice versus competitors across ChatGPT, Perplexity…

Thibaultbm/claude-seo-geo · 121 tokens

obsidian-brain

Build a local Obsidian vault that acts as the company and founder second brain, the knowledge layer every other skill reads before acting and writes back to. Input: your raw material (PDFs, decks, transcripts, email, WhatsApp exports, loose notes). Output: a structured, linked vault (domain hubs, maps of content…

Thibaultbm/claude-seo-geo · 135 tokens