How this list is maintained. Really Good GEO reviews each source before publishing a claim that depends on it. The "last reviewed" date on each entry is the date the linked page was checked for currency. Publisher documentation changes; if you notice a link that no longer supports a Field Guide claim, please email hello@reallygoodgeo.ai.
OpenAI
- OpenAI crawlers — Publisher: OpenAI · Description: official documentation for OAI-SearchBot, GPTBot, and ChatGPT-User, including their distinct purposes and site controls · Last reviewed: 2026-09-10
- Web search tool — Publisher: OpenAI · Description: developer documentation for the OpenAI web-search tool, including citation return in responses · Last reviewed: 2026-08-28
Anthropic
- Web search tool — Publisher: Anthropic · Description: developer documentation for Claude's web-search tool, including citation handling · Last reviewed: 2026-09-10
- Anthropic web crawlers — Publisher: Anthropic · Description: official purpose and robots.txt guidance for ClaudeBot, Claude-SearchBot, and Claude-User · Last reviewed: 2026-09-11
- Structured data — Publisher: Google · Description: official documentation for structured data in Google Search, including the requirement that markup describe visible page content · Last reviewed: 2026-09-10
- Google common crawlers — Publisher: Google · Description: current crawler and product-token documentation, including what Google-Extended controls and its separation from Google Search inclusion and ranking · Last reviewed: 2026-09-11
- AI features and your website — Publisher: Google · Description: official access and preview-control guidance for AI Overviews and AI Mode in Google Search · Last reviewed: 2026-09-11
Perplexity
- Perplexity crawlers — Publisher: Perplexity · Description: documentation for PerplexityBot, Perplexity-User, robots.txt controls, and published IP ranges · Last reviewed: 2026-09-10
Standards
- Schema.org — Publisher: schema.org (joint founding sponsors Google, Microsoft, Yahoo, Yandex) · Description: shared vocabulary for structured data on the web · Last reviewed: 2026-08-28
- The Robots Exclusion Protocol — Publisher: robotstxt.org · Description: the robots.txt convention and its rules · Last reviewed: 2026-08-28
What this list is not. This is not an endorsement of any product or ranking of engines. The entries here are the specific documents Really Good GEO relies on when a Field Guide page states an externally verifiable fact about a product's behavior, a crawler, or a standard. RGG frameworks and testing protocols are attributed to Really Good GEO directly, not to these sources.