The CiteFuel Blog

Practical GEO engineering — no hype, methodology attached. New posts weekly.

AI Crawler User Agent Strings: Complete 2026 Reference List

A robots.txt reference separating requesting crawlers from non-requesting product-control tokens such as Google-Extended and Applebot-Extended.

2026-06-12 · 8 min read

llms.txt Format Guide: Exact Spec, Fields, and Examples (2026)

A practical guide to the voluntary llms.txt proposal, its Markdown convention, validation limits, and copy-paste examples. Google Search ignores llms.txt.

2026-06-12 · 9 min read

Robots.txt for AI Crawlers: The Complete 2026 Configuration Guide

A policy guide to 14 crawler and product-control tokens, the training/retrieval split, and three reviewable robots.txt examples for explicit publisher intent.

2026-06-12 · 9 min read

Schema Markup for AI Search: What LLMs Actually Read in 2026

The five JSON-LD blocks AI systems actually use, the five breakages that silently void them, and how to validate your structured data the way an AI parser reads it.

2026-06-12 · 8 min read

What Is GEO? The 2026 Guide to Generative Engine Optimization

Everything that actually matters in GEO: how AI systems pick sources, the five Readiness categories, what to fix first, and what to ignore.

2026-06-11 · 9 min read

How to Add llms.txt to Your Site (Astro, Next.js, WordPress)

Step-by-step implementation of the voluntary llms.txt proposal for three common stacks, with format validation and honest limits.

2026-06-11 · 8 min read

Does Your Site Appear in ChatGPT? Here's How to Check

A practical test protocol for ChatGPT, Perplexity, and Google AI Overviews — plus what each failure pattern means and the configuration fix for it.

2026-06-11 · 8 min read

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