# Technical Implementation

> How a site's implementation decides what crawlers can see: rendering, and telling real crawlers from impostors.

- URL: https://geo.casa/implementation/
- Hub
- Reviewed: 2026-10-25

Content only counts if crawlers receive it. These entries cover what happens between a request and the HTML a crawler gets back. Does JavaScript run? Is a request that claims to be a crawler really one?

## Start here

1. [JavaScript rendering and AI crawlers](https://geo.casa/implementation/javascript-rendering-ai-crawlers/) — what Googlebot renders, and what a 2024 study found most AI crawlers do not.
2. [Verify AI crawler traffic in server logs](https://geo.casa/implementation/verify-ai-crawlers/) — confirm a request is really from Google, OpenAI, Anthropic or Perplexity.
3. [HTTP status codes and crawlers](https://geo.casa/implementation/http-status-crawlers/) — how 4xx, 5xx and redirects change what gets indexed.
4. [Page experience and Core Web Vitals](https://geo.casa/implementation/page-experience/) — Core Web Vitals and how much they matter.
5. [AI agents and your website](https://geo.casa/implementation/ai-agents/) — how browser agents read a site, and what helps them.

## Sources

- [Google Search Central: Understand JavaScript SEO basics](https://developers.google.com/search/docs/crawling-indexing/javascript/javascript-seo-basics)
- [Google: Verify requests from Google crawlers and fetchers](https://developers.google.com/crawling/docs/crawlers-fetchers/verify-google-requests)