Which rule does the AI crawler read first when entering a site, and how do robots.txt and llms.txt divide labor?
Which rule does the AI crawler read first when entering a site? First read the crawling permission, then read the overview file. robots.txt determines whether a crawling agent can enter and which directories it can enter; llms.txt determines the overview of the site to be used after the model is allowed to enter. The third-party division of access control for AI crawlers is consistent with this: crawling and access permissions are responsible for robots.txt, and path guidance when the model is reading the page is responsible for llms.txt. Both are not at the same level, and one is not equal to the other, and it is also completed.
This robots.txt controls whether it can capture
This file is written according to user agent grouping to write allow and deny rules, model crawlers usually have their own proxy identifiers, so there will be three options when configuring: allow all, allow only crawling for search, and allow only for scenarios outside training and retrieval. The judgment basis is not technical feasibility, but content authorization standards - reserving access for search engines and reserving access for model batch crawling are two types of decisions in the same file.
Two things to pay attention to: first, the rules take effect on the directory, if the entire site directory is disabled, it will not take effect automatically after separately enabling a column; second, after making changes, verify the real crawling records instead of just looking at the file syntax. The site's Robots.txt configuration is responsible for generating and maintaining this layer of rules.
llms.txt manages what is read after entering.
The overview file solves the issue of「The model does not need to traverse the entire site」: a site name description, an abstract, and a list of entry points grouped by topic. It does not provide access permission and does not change the crawling quota, so it is a common misconception to treat it as a new robots file. For content cited by AI, its role is closer to a directory page - allowing the model to find sections and representative articles first, and then decide which articles to read in depth.
This file: llms.txt does not need manual maintenance within the site and can be automatically generated by the system. It forms part of the collection of backend modules related to GEO and SEO, which includes features such as site maps, link push, and other capabilities. These modules (modules) cover adjacent links such as crawling permissions, list generation, and content overview.
| Project | Robots.txt | llms.txt |
|---|---|---|
| The questions answered | Can it crawl, which directories can be crawled? | What order to read after entering? |
| Effective object | Access permission of crawling proxy | Overview and entry of model proxy |
| Who maintains | The site owner decides the scope of release | Can be automatically generated by the site |
| Common misunderstandings | Believing that release will definitely be cited | Believing that it can replace crawling rules |
| Verification method | Check if the real crawling records appear | Check if the overview is consistent with the actual page |
The configuration order of the two files
The order suggestion is to define the permissions first, then define the overview. First, clarify which content is allowed to be crawled by the model and which is only given to the search index, and put the conclusion in the crawling rules; then confirm that the overview file is consistent with the actual column, and key columns should have representative entries. If the site operates multi-language and multi-brand at the same time, both files should be checked separately according to the site to avoid using the main site's rules to cover the content of the sub-site.
Third-party long-term monitoring of a batch of sites also gives a current situation: Seven out of eleven homes later allow at least one AI crawler to crawl, only four have published overview files. That is, most sites have only done the permission level, and the overview level is still blank.
Common questions
Will allowing AI crawlers always be cited?Not necessarily. Permission only determines whether it can be caught, whether it can be cited depends on whether the content can be extracted into an independent answer.
Is it okay to only write llms.txt?No. Without crawling permission, the overview file itself will not be read.
How long will it take for the changes to take effect?Relies on the read frequency of the opponent's proxy, a more reliable approach is to regularly test a fixed batch of questions monthly rather than waiting for the overall traffic to change.
Will banning training class crawling affect search inclusion?Let's take a separate look: the proxies reserved for search and those for training purposes are different identifiers, and rules written by grouping will not interfere with each other.