Google 將 7 種搜尋內容控制方式整理至同一頁，作者解説各自適用時機

Google did not invent a new off switch on October 21. It finally put all the existing controls on one page. That clarity is useful, because most sites I audit use the wrong control for the job.

I spend a lot of my week inside Search Console and robots files for client sites, and one mistake keeps showing up. Someone wants a page out of AI Overviews, so they block it in robots.txt. Or they want a page gone from search entirely, so they add a nosnippet tag. Neither does what they think it does. So when Google updated its "Control what you share with Google Search" documentation on October 21, 2026, I read it properly, because it finally groups the options in one place instead of scattering them across five help pages.

Here is the honest summary first. Google says all of these options already existed. The update brings them together, adds rows for the robots meta tag, data-nosnippet and X-Robots-Tag, and for the site-wide Search generative AI control in Search Console, and clarifies that the page covers Google Search. It does not mention Google-Extended or AI training. That last point matters, and I will come back to it.

What actually changed on October 21

Three things are worth your attention.

First, the AI control is now visible on the main overview of content controls. That control lives in Search Console settings and rolled out to all sites globally on August 31, 2026. Turning it on removes a site from AI Overviews, AI Mode and the generative features in Discover. It is a site-wide switch, not a per-page setting.

Second, Google's documentation now explains how nosnippet and data-nosnippet apply to AI Overviews and AI Mode, alongside the robots meta tag documentation for AI Mode. In plain words, the snippet controls you already knew now have a stated AI meaning too.

Third, there is a small but useful reporting change from earlier in October. If a subdomain or subfolder property overrides the parent domain's AI setting, the top-level domain property owner now sees a notification on that page. Before that, a child property could quietly opt back in and nobody would notice. If you manage a site with separate properties for a blog, a shop and a help center, check this first.

The controls, in plain English

Think of these as different tools, not different strengths of the same tool.

1. Robots meta tag and X-Robots-Tag. This is how you tell Google not to index a page, or not to follow its links. The meta tag goes in the page head. X-Robots-Tag does the same job from the server header, which is handy for PDFs and other files that have no head section. Use this when the page should not be in search at all.

2. Robots.txt. This is a crawling control, not an indexing control. Blocking a page in robots.txt stops Googlebot from fetching it, but it does not guarantee the URL disappears from search. I still see blocked URLs show up as bare links. Use robots.txt to save crawl budget and keep bots out of admin areas and faceted filter URLs. Do not use it as your only way to remove a page.

3. Nosnippet and data-nosnippet. Nosnippet tells Google not to show a text snippet for a page. Data-nosnippet is the finer version. You wrap one part of a page in it and Google will not use that part in a snippet. This is useful when a page should rank but one paragraph, a price, or a phone number should not be quoted. It is not a removal tool.

4. Search Console removals. This is the emergency lever. When something sensitive is live and indexed, a removal request hides it fast while you fix the underlying page. It is temporary by design. If you never fix the page itself, it comes back. I treat removals as first aid, not treatment.

5. Login or password protection. If a page genuinely should never be public, put it behind a login. No tag beats a real barrier. Staging sites, internal docs and client previews belong behind a login, not behind a noindex tag you hope someone remembers.

6. The Search generative AI control. This is the new headline switch. One setting in Search Console, site-wide, removes the site from AI Overviews, AI Mode and Discover's generative features. Use it only when you have made a deliberate business decision about AI search, not as a panic reaction to one bad week of traffic. It is broad, and broad switches deserve a meeting, not a click at midnight.

7. Per-page judgment. This is the part Google cannot decide for you. Some pages should stay fully visible, some should rank without a snippet, and some should leave AI features while staying in classic search. The documentation gives you the levers. Your content strategy decides which lever each page gets.

My decision checklist before I touch any control

I run through this list before changing anything on a client site, and it has saved me from at least one embarrassing reversal.

1. What exactly do I want to stop: indexing, snippet display, AI features, or crawling? Name one. If you cannot name it, you are not ready to change a setting.
2. Is this one page, one section, or the whole site? A site-wide switch for a one-page problem is how good content disappears.
3. Is the page already indexed? If yes, a robots.txt block alone will not remove it. You need a noindex tag and a recrawl, or a removal request first.
4. Is there a child property that could override me? Check the Search Console AI control page for override notifications, especially on multi-property sites.
5. Who else depends on this page? A help article that feeds AI answers might also feed your support team. Removing it has a cost.
6. What will I measure after the change? Note the date, the setting, and the pages affected. Otherwise you will never know if the change helped or hurt.
7. Is there a login barrier where one belongs? If the content was never meant to be public, fix access first and tags second.

What I would not do

I would not treat the AI control as an AI training opt-out, because Google's updated page does not present it that way. It covers Google Search features, and it does not mention Google-Extended or AI training. If training is your concern, that is a separate conversation with separate controls, and you should not assume one switch covers both.

I would not block a whole site in robots.txt to escape AI Overviews either. You would lose classic search visibility for the same pages, and the block itself does not guarantee removal. And I would not add nosnippet everywhere "just in case." A page with no snippet is a page that is harder to click, and that cost is real even when the AI benefit is unclear.

FAQ

Does the Search generative AI control remove my site from Google Search entirely? No. It removes the site from AI Overviews, AI Mode and Discover's generative features. Classic search listings are a separate question.

If I block a page in robots.txt, is it gone from search? Not necessarily. Robots.txt controls crawling, not indexing. For removal, use a noindex tag and let Google recrawl, or use a Search Console removal request for urgent cases.

Do I need new schema or a new text file for AI search? Google's own guidance has said structured data is not required for AI Overviews or AI Mode, and you do not need to create new machine-readable files for them. Good structured data still helps classic rich results and clarity, but it is not a ticket into AI features.

Should every site opt out of AI features now? No. That is a business decision, not a default. Some sites will gain from AI citations and the more prominent links Google announced for AI Mode on October 15. Others, especially publishers whose full answer is the product, may reasonably opt out. Decide page by page where you can, and site-wide only when the case is genuinely site-wide.

The bottom line

Google did not hand us a magic off switch. It handed us a clearer map of the switches we already had, with the AI control finally sitting on the same page as the rest. The win is not in clicking faster. It is in naming what you actually want to stop, picking the one control that does that job, and writing down what you changed.

If you want a second pair of eyes on your setup, my portfolio is at https://www.shanzyseoexpert.com/ . I am Shanzy Saleem, an SEO specialist and web developer based in Lahore, and this is the kind of unglamorous control check I run on client sites before any bigger SEO work starts. Get the controls right first. The rankings conversation gets much easier after that.