How each AI engine works

How Does AI Decide Which Hotels to Recommend?

The five engine-specific guides on this site explain one engine at a time. This one walks a single guest question through all five at once.

AI engines pick which hotels to recommend in roughly three steps, retrieving candidate sources for the question, fusing what those sources say into one coherent answer, and generating that answer, but which sources each engine retrieves from differs by engine, which is why the same hotel can be named by one AI assistant and skipped entirely by another for the exact same question.

Key takeaways

  • Every engine follows some version of retrieval, then source fusion, then answer generation, the details differ, the shape doesn't.
  • ChatGPT's web search has been publicly reported to run on Bing's index; Claude's web search tool has been publicly reported to use Brave's search API.
  • Gemini and Google AI Overviews both draw on Google's own Search and Maps data, which is why Google Business Profile accuracy matters more for those two specifically.
  • Perplexity is built around live retrieval and visible citation for nearly every claim, rather than leaning on a pre-built index alone.
  • In one real scan of a Prague hotel, the same property scored 15% on Gemini and 0% on Claude for the same 60 questions, run the same week.

The short version: retrieval, then fusion, then an answer

Strip away the branding and all five major AI engines do some version of the same three-step process when a traveler asks a recommendation question. First, retrieval: the engine gathers a set of candidate sources it thinks are relevant, a mix of an existing search index, live crawling, and in some cases a maps or business-listing database. Second, source fusion: it weighs and blends what those sources say, resolving disagreements (one source says 40 rooms, another says 45) and deciding which facts to state with confidence. Third, generation: it writes the actual answer, choosing which one to three hotels to name from everything it just gathered.

The five guides on this site that cover ChatGPT, Claude, Gemini, Perplexity, and AI Overviews individually each walk through one engine's version of this process in detail. This page is the cross-engine view: the same question, run through all five at once, and what actually differs between them.

Walking one guest question through the pipeline

Take a real, common query: "best boutique hotel in Prague for a weekend trip." A guest types or speaks this into ChatGPT, Gemini, Claude, Perplexity, or Google, expecting a short, confident answer, not a list of ten links to sift through themselves.

Behind that one sentence, each engine now goes looking for candidate hotels, and this is exactly where the paths start to diverge, because "going looking" means something different depending on which search infrastructure sits behind the assistant.

Retrieval: what each engine is actually searching

ChatGPT's web-browsing and search feature has been publicly reported to run on Bing's search index as its underlying retrieval layer, meaning a hotel's standing in Bing's index is a real, if indirect, input into what ChatGPT can find. Claude's web search tool has been publicly reported to use Brave's search API for the same purpose, a different index with its own crawl and ranking behavior.

Gemini and Google AI Overviews both draw directly on Google's own Search index, plus Google Maps and Business Profile data for real-world, location-based questions, since both products are built and operated by Google itself. Perplexity leans less on a single pre-built index and more on live retrieval at query time, fetching and reading current pages rather than relying purely on a cached index, which is a meaningful part of why it visibly cites nearly everything it states.

None of this is published by any of these companies as an official, hotel-specific ranking algorithm. It's public, reported infrastructure, which sources feed which engine, not a documented formula for which hotel wins.

Source fusion: turning several sources into one answer

Once an engine has candidate sources, it has to reconcile them. If your own website, a Booking.com listing, and a TripAdvisor page all describe your hotel slightly differently, the AI has to decide which version to trust, or which parts to combine. Consistent, structured, matching facts across sources make this step easy. Conflicting facts make it more likely the AI either states something wrong or quietly leaves your hotel out of the answer rather than risk stating something it can't verify.

This is also the stage where third-party authority tends to win by default: an OTA listing that's been indexed for years, with thousands of consistent data points behind it, is often an easier source for an AI to trust than a hotel's own site, unless that site's own signals are just as clean.

Why the same hotel can win one engine and lose another

Because retrieval differs by engine, a hotel that's well-indexed in Bing but thin on Google Business Profile data might do reasonably on ChatGPT while barely showing up on Gemini, or the reverse. A hotel with strong, frequently-updated third-party citations but a site Perplexity rarely crawls might do well everywhere except Perplexity specifically.

This is the practical reason checking only one AI assistant by hand gives a skewed picture: the gap isn't always about the hotel's overall quality or content, it's often about which specific retrieval path failed for that one engine.

A real worked example: one hotel, five engines, one week

Golden Well Hotel, a boutique property in Prague, is one of the real, published case studies on this site, and its results make the point concretely. Across 295 real, non-branded traveler questions run through five engines in the same week, the same hotel scored 15% detection on Gemini, 11.7% on Perplexity, 8.3% on ChatGPT, and 0% on both Claude and Google AI Overviews.

That's the same website, the same reviews, the same structured data, scoring anywhere from 15% to 0% depending purely on which engine was asked. When the AI engines didn't name Golden Well, they routed travelers to Booking.com, TripAdvisor, a French-language travel blog, and a hotel-editorial site instead, a real, visible answer to "who wins when you don't."

The trust signals every engine shares, despite different retrieval

Underneath the different retrieval paths, all five engines reward roughly the same underlying things: a site AI crawlers can actually reach, structured data that states facts plainly, name-address-phone consistency across the sources each engine pulls from, and content that looks current rather than stale. None of these five inputs are unique to one engine. They're the shared floor every engine's fusion step is working from, whichever index or crawl fed it in the first place.

That's also why a single technical fix, correcting a Google Business Profile mismatch, say, can move the number on more than one engine at once, even though the engines never talk to each other.

What this means in practice

Checking one AI assistant by hand and calling it representative is the most common mistake this cross-engine view corrects. A hotel invisible on ChatGPT specifically might be doing fine on Gemini, and a hotel that looks fine because someone happened to test Perplexity might be completely absent from Google AI Overviews. The only way to know the real spread is to ask the same real question across all five, on a repeatable basis, not once.

It also changes how a fix gets prioritized. A hotel scoring 0% on Claude and Gemini but fine everywhere else has a narrower, more specific problem than a hotel scoring near 0% across all five, and the two situations call for different next steps, one is likely an isolated retrieval gap, the other points at something more fundamental like blocked crawlers or missing structured data across the board.

Why this is worth tracking on a schedule, not a one-time check

AI answers aren't static. Search indexes update, engines change how they weigh sources, and a hotel's own third-party listings shift as reviews accumulate or a directory entry goes stale. The Golden Well numbers above are a snapshot from one real scan, not a permanent score, which is exactly why a single manual check, however careful, only tells you about that one moment.

The guide on measuring hotel AI visibility, linked below, covers the three numbers worth tracking over time (detection rate, mention rank, and the per-engine breakdown shown here) and how often it's actually worth re-checking.

Questions

Do all five AI engines pull from the same sources?

No. ChatGPT's search has been publicly reported to run on Bing, Claude's on Brave, while Gemini and AI Overviews draw on Google's own Search and Maps data, and Perplexity leans more on live retrieval than a single pre-built index. The shared trust signals (crawlability, structured data, consistent listings) matter to all five regardless.

Can a hotel see exactly which sources an engine used for a specific answer?

Perplexity shows visible citations for most claims, which makes this the most transparent of the five. The others don't consistently expose their sourcing in the answer itself, so the closest a hotel can get is checking the individual engine guides and testing real questions directly.

If a hotel ranks #1 on Google, does that guarantee an AI mention?

No. AI Overviews is a separate, generated layer above the ranked organic results, and the other four engines don't use Google's organic rankings as an input at all. Ranking well on Google helps but doesn't carry over automatically.

Why did Golden Well Hotel score 15% on one engine and 0% on another for the same week?

The underlying site, reviews, and structured data were identical across all five checks. The difference came down to which sources each engine actually retrieved from and cited, not a difference in the hotel itself, which is the central point this guide is making.

See where your own hotel stands.

The calculator takes thirty seconds, costs nothing, and shows its math.