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You log into analytics, see traffic slipping a little, and shrug it off as seasonality. Then a founder pings you on Slack:
“I just asked Perplexity about our category. We weren’t mentioned once. But our competitor was.”
That is the real risk now. It’s not just “Will Google index my page?” anymore. It’s “Will AI crawlers quietly strip mine my content for everyone else’s answers while sending me fewer visits?”
At the same time, you can’t just rage-block everything. Your AI SEO efforts still depend on being visible in AI-powered search, AI Overviews and answer engines. You want control, not disappearance.
This is where robots.txt, llms.txt and smarter content licensing decisions come in. The goal is simple: let the right bots in, keep the wrong ones out, and make sure your best pages are used in ways that actually help your brand.
Let’s unpack that in plain language and turn it into something you can actually implement.
The New Problem: AI Wants Your Content, Your SEO Wants the Clicks
Over the last two years, the web has quietly filled up with two kinds of bots:
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Crawlers that power classic search - think Googlebot, Bingbot.
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Crawlers that power models and assistants - GPTBot, OAI-SearchBot, Perplexity, Anthropic’s bots, and many more.
The first group is familiar: they crawl, index, and send users back to your pages. That exchange has always been fragile, but at least it was clear: free content in return for discoverability and traffic.
The second group is different. They crawl to:
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Train large language models.
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Retrieve snippets in real time for tools like ChatGPT, Gemini or Perplexity.
Your content may be used to:
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Answer questions without a click.
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Summarize a whole topic based on your work.
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Recommend competitors right next to you.
Cloudflare’s own data shows how serious this has become: they now block known AI crawlers by default for new domains and offer Pay Per Crawl so publishers can charge AI companies for access.
So you’re stuck between two bad extremes:
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Block every AI bot and risk disappearing from AI search.
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Allow everything and watch your content power answers that don’t even mention you.
You need a middle path: control, not chaos. And that starts with understanding what your existing levers actually do.
What robots.txt Really Controls In an AI World
Most SEO teams already know robots.txt as “the file that tells Google what to crawl or not”. Technically, it is a simple text file at yourdomain.com/robots.txt that sets rules like:
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Which bots (user-agents) are allowed.
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Which directories or URLs they can and cannot access.
Good actors - like Googlebot and OpenAI’s GPTBot - explicitly state that they respect robots.txt and will not crawl content you disallow.
However, there are a few realities you need to keep in mind:
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robots.txt is voluntary. Rogue scrapers and some unverified AI bots may still ignore it.
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If you block AI crawlers that power useful features (like OAI-SearchBot for ChatGPT search), you may also lose visibility in those summaries and citations.
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If you over-block, you can accidentally hurt your AI SEO visibility and long-term demand.
A more nuanced use of robots.txt looks like this:
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Allow Googlebot, Bingbot and other classic search crawlers on most public pages.
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Decide bot-by-bot for AI agents:
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Allow OAI-SearchBot or similar if you want to appear in AI answers.
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Disallow GPTBot or others on premium or sensitive sections where training/repurposing is not acceptable.
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In other words, robots.txt is still your gatekeeper for access. It doesn’t say how AI can reuse your content, and it doesn’t tell them which pieces are most important. For that, you need another layer.
Meet llms.txt: Not a Blocker, But a Map for AI
The newer kid on the block is llms.txt. Because the name looks so similar, a lot of people assume it is “robots for LLMs”. It is not.
Think of llms.txt as a kind of “AI sitemap” or “treasure map” that lives at yourdomain.com/llms.txt. Instead of saying “do not enter”, it says:
“If you’re an AI, these are the URLs that best represent what we want you to learn, understand and possibly cite.”
Guides from SEO and AI tooling companies describe llms.txt as a curated list of LLM-friendly content: high-quality explainers, canonical guides, pricing pages, and resources you want AI to use as references.
You can use it to:
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Point AI systems at your most up-to-date, accurate content.
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Avoid them relying on old PDFs, random blog posts or third-party summaries.
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Nudge answer engines toward your brand voice and official data.
A typical llms.txt might include:
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Your main product and feature pages.
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Category and comparison pages that define your positioning.
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Source of truth hubs for statistics, definitions and FAQs.
The crucial thing: llms.txt does not replace robots.txt. It supplements it.
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robots.txt = who can come in, and where they can walk.
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llms.txt = what you want them to actually pay attention to and reuse.
Once you accept that division of roles, the question changes from “Should I block AI completely?” to “What do I want AI to see first when it learns about my brand?”
When You Should Block AI Crawlers, and When You Probably Shouldn’t
You don’t need a one-size-fits-all policy. You need a content-aware policy.
For most brands, the smartest move is to decide by content type and business value, not emotion.
Here’s a simple way to think about it:
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Content that directly drives revenue and has unique differentiation.
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Content that explains your category and educates the market.
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Content that is easily replaceable by competitors or UGC.
Now translate that into AI access decisions:
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For premium, paid or highly proprietary content (internal playbooks, deep research, gated courses), it often makes sense to block AI crawlers completely in robots.txt and via infra tools. You don’t want this quietly training models or being summarized elsewhere.
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For top-of-funnel explainers and category guides, visibility in AI search can actually grow your brand. Blocking everything here can hurt you more than it protects you.
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For basic utility pages (e.g., simple glossary definitions), you can often be neutral: allow it, but prioritize your more strategic URLs in llms.txt.
At the same time, industry bodies like the IETF are actively working on technical standards to distinguish traditional search crawlers from generative answer engines, so that you can block one while still allowing the other.
In practice, your policy might look like:
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We block training-oriented bots on premium and member areas.
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We allow AI assistants that send traffic or citations for public education content.
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We invest in getting our best pages into llms.txt so AI sees the strongest version of our story.
The goal isn’t purity. The goal is to make intentional trade-offs instead of letting every AI company decide for you.
Content Licensing, 402 Codes and Infra Tools in Plain English
Even with perfect robots.txt, you eventually hit a bigger question:
“If AI wants our content, can we ask to be paid for it?”
That’s where content licensing and infrastructure tools come in.
Cloudflare has started to reshape this space with features like AI Crawl Control and Pay Per Crawl. In simple terms, they let site owners:
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Monitor which AI bots are hitting their site.
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Block specific AI crawlers by default.
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Return a 402 Payment Required status instead of just “Forbidden”, along with a message that explains how to license that content.
So instead of a dead end, the conversation looks like:
“To access this content, contact partnerships@yourbrand.com or use our paid API.”
That moves you from “unpaid training data source” to “potential licensing partner”. It also gives you leverage when AI companies want high-quality content but can’t just scrape it for free anymore.
Here’s a simple comparison to keep in mind:
| Goal | Practical setup |
|---|---|
| Maximize reach & citations | Allow key AI crawlers, highlight URLs in llms.txt, no 402 on public guides. |
| Protect premium content | Block AI bots via robots.txt & infra, consider 402 for negotiation. |
| Mix of visibility + revenue | Allow some bots, charge others via Pay-Per-Crawl / 402-based content licensing. |
You don’t need Cloudflare specifically to start thinking this way, but tools like this make it much easier to implement decisions at scale instead of writing theory documents no one can enforce.
Using Data to Decide What to Protect vs What to Promote
The hard part isn’t writing robots.txt rules. It’s answering a more strategic question:
“Which URLs are actually valuable in AI search, and which ones can we safely lock down?”
If you guess, you’ll probably protect the wrong things and expose the assets that matter most.
This is where AI search metrics and visibility data become critical. A platform like Serplux can help by:
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Tracking which of your pages are showing up in AI-style answers, summaries or overviews.
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Identifying URLs that are frequently cited vs URLs that never seem to appear.
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Mapping which keywords or topics drive those AI mentions.
Once you can see that:
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Page A is heavily used in AI answers for high-intent queries,
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Page B almost never appears anywhere,
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Page C is indirectly powering competitor mentions via third-party reviews,
your content licensing and crawl decisions get much smarter.
In practice, you might decide:
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These three product explainers are our crown jewels in AI Overviews. We keep them public, optimize them for AI SEO, and add them to llms.txt so they are reused in the best possible way.
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These long-form reports are part of our paid edge. We tighten access, block AI crawlers, and only allow use through explicit deals.
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These older blog posts are low-impact. We don’t worry much about who crawls them.
Serplux’s role is not to tell you “block everything” or “open everything”. It is to show you which URLs matter most in AI ecosystems, so you can protect what is strategic and promote what fuels awareness.
A Simple Playbook for Your AI Crawler Policy
If this still feels abstract, it helps to collapse everything into a clear, repeatable process. You can start with a basic 4-step loop and then refine it:
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Audit your current exposure
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List your top 50-100 pages by revenue impact, lead generation and authority.
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Use logs, tools and platforms like Serplux to see which of those pages appear in AI answers, summaries, or AI Overviews today.
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Segment URLs by intent and sensitivity
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Group content into:
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Public education (blog guides, glossaries, category explainers).
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Commercial and product pages (pricing, comparisons, feature breakdowns).
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Premium or sensitive content (courses, proprietary research, member areas).
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Decide where visibility is an asset and where unlicensed reuse is a threat.
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Design your combined robots.txt + llms.txt + infra strategy
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In robots.txt, explicitly:
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Allow classic search bots on all public content.
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Allow or block specific AI bots (e.g., GPTBot, OAI-SearchBot) per segment.
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In llms.txt, curate a list of “source of truth” URLs you want AI to rely on.
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In your infra (Cloudflare, Vercel, etc.), configure rules to:
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Block or rate-limit unverified AI crawlers.
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Return 402s and custom content licensing messages where appropriate.
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Measure and iterate with AI visibility in mind
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Track how often you are cited or mentioned over time.
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Watch for bots that ignore rules and adjust infra-level protections.
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Use tools like Serplux to see whether your changes improved AI visibility for important topics or accidentally erased you from key answer surfaces.
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Over time, this evolves into a mature policy you can write down, share with legal, and align with leadership on. It becomes less “Are we scared of AI?” and more “We have a clear stance on who can use our content, for what, and at what price.”