Configuring robots.txt for AI Crawlers
Understanding AI Crawlers#
AI crawlers are automated bots operated by AI companies to discover, index, and learn from web content. Unlike traditional search engine crawlers (Googlebot, Bingbot) that build search indexes, AI crawlers feed content into large language models for training data and real-time retrieval-augmented generation (RAG). When someone asks ChatGPT a question and it browses the web, it uses a crawler. When Perplexity generates a cited answer, it uses a crawler. When Claude is given a URL to read, it uses a crawler. Each of these systems respects robots.txt directives — which means your robots.txt file directly controls whether your content can appear in AI-generated answers. If you block AI crawlers, your content becomes invisible to the fastest-growing discovery channel on the internet.
The Major AI Crawlers#
There are currently 17 known AI crawlers actively scanning the web. Understanding which company operates each bot helps you make informed decisions about access control. The major players are listed below.
- GPTBot — OpenAI's primary training and retrieval crawler.
- ChatGPT-User — OpenAI's real-time browsing agent (when users click 'Browse').
- ClaudeBot — Anthropic's crawler for Claude's web access.
- Claude-Web — Anthropic's secondary web retrieval agent.
- PerplexityBot — Perplexity AI's answer engine crawler.
- Google-Extended — Google's AI training crawler (separate from Googlebot).
- Amazonbot — Amazon's AI and Alexa knowledge crawler.
- Bytespider — ByteDance's crawler for TikTok and Doubao AI.
- cohere-ai — Cohere's enterprise AI training crawler.
- Meta-ExternalAgent — Meta's AI training crawler for Llama models.
- Applebot-Extended — Apple's AI features training crawler.
- anthropic-ai — Anthropic's training data crawler.
- Diffbot — Knowledge graph builder used by many AI systems.
- Timesbot — AI-related crawler from the news industry.
- Webz.io — Web data platform crawler feeding AI pipelines.
- Kangaroo Bot — Australian AI search crawler.
- PetalBot — Huawei's AI search crawler.
Recommended robots.txt Configuration#
For maximum AI visibility, you should explicitly allow all major AI crawlers. The recommended approach is to start with broad access and then selectively block only what you need to protect (such as admin pages or private content). Here is a complete robots.txt configuration that optimizes for AI visibility while maintaining sensible access controls.
# Traditional search engines
User-agent: Googlebot
Allow: /
User-agent: Bingbot
Allow: /
# AI Crawlers - Allow for AI visibility
User-agent: GPTBot
Allow: /
User-agent: ChatGPT-User
Allow: /
User-agent: ClaudeBot
Allow: /
User-agent: Claude-Web
Allow: /
User-agent: PerplexityBot
Allow: /
User-agent: Google-Extended
Allow: /
User-agent: Amazonbot
Allow: /
User-agent: cohere-ai
Allow: /
User-agent: Meta-ExternalAgent
Allow: /
User-agent: Applebot-Extended
Allow: /
User-agent: anthropic-ai
Allow: /
User-agent: Bytespider
Allow: /
# Block sensitive paths for all bots
User-agent: *
Disallow: /admin/
Disallow: /api/
Disallow: /private/
# Sitemap
Sitemap: https://example.com/sitemap.xmlBest Strategy for AI Visibility#
The optimal strategy depends on your business model. Content publishers who earn revenue from traffic may want to selectively allow crawlers that provide attribution (PerplexityBot links back to sources) while blocking pure training crawlers. SaaS companies and service businesses benefit most from maximum exposure — every AI citation is a potential lead. E-commerce sites should allow all crawlers to ensure products appear in AI shopping recommendations. Whatever your strategy, avoid the common mistake of using a blanket 'Disallow: /' for all unknown bots, as this blocks AI crawlers by default. Instead, use an explicit allow-list approach. Review your robots.txt quarterly as new AI crawlers emerge regularly.
A blanket 'Disallow: /' for unknown bots blocks all AI crawlers by default. Use an explicit allow-list approach instead.
Frequently Asked Questions
No. AI crawlers are separate from search engine crawlers. Allowing GPTBot does not affect your Google rankings. In fact, appearing in AI-generated answers can drive additional traffic and brand awareness that complements traditional SEO.
Yes. robots.txt supports per-user-agent rules. You can allow PerplexityBot (which cites sources) while blocking Bytespider (used for training). Each entry is independent.
The major AI companies (OpenAI, Anthropic, Google, Perplexity) have publicly committed to respecting robots.txt. Some smaller or less scrupulous crawlers may not. For those, you would need server-level blocking.