Background
What are AI crawlers?
AI crawlers are the automated user-agents that AI products send to your site so they can read it, index it, or cite it back to a user.
They are not all the same. Some bots collect training data. Some fetch pages live when a user asks a question. Some build the search index that powers AI Overviews. Your robots.txt controls each one independently.
If you want to appear in AI answers, the live-answer and retrieval bots are the ones that matter. The training crawlers are a separate, slower, content-policy decision.