AEO · Answer engine optimisation
AEO Agency: Become the Source AI Assistants Cite
Castle’s answer engine optimisation service gets your pages found, quoted and credited when an AI assistant answers a question in your market.
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A specialist AEO agency
AI answers are the new results page.
Most AI assistants now search before they answer. They run their own query, pull together a handful of pages, and write their reply from what they find. Answer engine optimisation is the work of making sure your page is one of the ones they pull, and that the part they lift is credited to you. Some people call this retrieval optimisation, because that's the exact step it's aimed at.
That's a different job to ranking well. A page can sit near the top of Google and rank well in terms of traditional SEO and still never get mentioned by ChatGPT, because the answer the assistant needed was buried halfway down a paragraph instead of sitting somewhere it could be lifted easily. Our AEO service rewrites and restructures your content so it can be pulled out whole, and builds the supporting evidence that gives a platform the confidence to name you as the source.
Answer engine optimisation services
What's included in our AEO services
A managed answer engine optimisation programme, built around the real questions your customers are asking AI and the pages that should be answering them.
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Question and prompt research
We start by working out what your market actually asks an AI assistant, rather than what they'd type into Google: the comparisons, the “best X for Y” prompts, the objections and the pricing questions. Then we map each one to the page that should own the answer and flag the ones nobody currently owns.
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Citation gap audit
We test those questions across ChatGPT, Perplexity, Google AI Overviews and Copilot and record who is cited. That gives you a starting point: where you already show up, where a competitor holds the answer, and where nobody has claimed it yet.
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Rewriting for extraction
We rewrite pages so the answer comes first and can stand on its own: a direct response early, headings written as the questions people actually ask, and definitions, prices or figures pulled out into their own lines rather than buried in a paragraph.
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Schema and structured data
FAQ, HowTo, Product and Organisation markup, plus consistent business details across your site and elsewhere, so a model can work out who you are and what's genuinely yours before it decides whether to quote you.
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Corroboration and citations
AI assistants are cautious about repeating a claim that it’s only seen once. We build the second and third sources it needs: reviews, directory listings, press coverage and a genuine presence on Reddit and Quora, so your figures are safe for a model to repeat.
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Citation tracking
We re-run the same set of questions on a schedule and report back on how often you're named, how that compares to competitors you name, and which page did the work. It's measured against being quoted, not against where you rank.
Why AEO
Why do I need an AEO agency?
The moment AI decides who to quote doesn't show up in your analytics. You'll notice a dip in clicks, but you won't see the answer that replaced them, or which competitor got named instead. AEO is the work of paying attention to a part of search you genuinely cannot see in a rankings report.
It also asks for a kind of writing most websites don't naturally do. AI search looks for a sentence that answers the question on its own, without needing the rest of the paragraph around it. Most content is written to keep someone reading, which tends to bury exactly that sentence.
Then there's trust. A large language model (LLM) won't usually repeat something specific, a price, a turnaround time, a statistic, unless it can find the same claim somewhere else too. Getting cited for anything concrete means that claim needs to exist off your site as well as on it, which is a different kind of work to writing a good page.
An AEO agency does all three together: finds the questions, restructures the answers, and builds the corroboration. At Castle we run it alongside GEO and traditional SEO so the same content earns rankings, citations and recommendations rather than one at the expense of another.
An AEO agency, like Castle, brings those three things together: finding the right questions, rewriting the answers, and building up that outside evidence. At Castle, we run this alongside GEO and traditional SEO, so the same piece of content does all three jobs rather than one at the expense of the others.
Answer engines
Which answer engines we optimise for
Each platform retrieves and attributes differently, so we optimise for how each one actually picks and shows its sources.
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ChatGPT
Most AI assistants use a process called retrieval-augmented generation: they search first, then write an answer from what they find. That's why a page can rank well on Google and still never get quoted by ChatGPT. AEO is aimed squarely at that search-and-select step — the retrieval step — where an assistant decides which pages to trust and lift from.
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Google AI Overviews
We structure pages so the passage that answers a prompt is self-contained and quotable, and build the off-site evidence that makes ChatGPT comfortable naming you as the source.
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Perplexity
Overviews lean heavily on pages that already rank and carry clean structured data, so we pair answer-first content and schema with the technical and traditional SEO underneath it.
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Microsoft Copilot
Perplexity shows its sources openly, which makes it the clearest place to measure AEO. We focus on well-supported, clearly attributed content that's easy to retrieve and cite.
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Google Gemini
We strengthen authority and discoverability across the Bing index Copilot draws on, and keep your business information consistent so the entity behind the claim resolves cleanly.
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Claude
We optimise for unambiguous entities and topical depth, so Gemini can establish what you do and treat your pages as a source it can rely on.
We track citations platform by platform, because being quoted in one doesn't guarantee you will be quoted in the next.
Industries we’ve worked with
AEO built around the questions your market asks
Claude is careful with claims it can't support, so we give it something to stand on: specific, checkable answers with the reasoning shown, and the dates and sources that let it quote you without hedging.
- SaaS
- Ecommerce
- Finance
- Healthcare
- Property
- Legal
- Education
- Professional services
- Technology
- Travel and hospitality
Why now
Why does my brand need AEO now?
- 900MWeekly active ChatGPT users
- 2BNGoogle AI Overviews monthly users
- 49%Of AI messages seek advice or answers
The question that matters is different in every sector. Someone shortlisting a SaaS tool wants a comparison; someone looking for a solicitor wants to know if they have a case; someone booking a clinic wants to know about waiting times, cost and reviews from other patients. The question set is the strategy, so we build it per industry rather than reusing a generic template. Sectors we’ve worked with include:
Answers are being written for your customers right now, whether or not you are a part of them. Every question that matters in your market has a set of sources an AI assistant currently reaches for, and that set is being decided while most competitors are still checking their rankings.
Citations tend to compound. Once a platform has found and corroborated your page for a question a few times, you become the safe, low-risk source it reaches for again. Getting there early is worth more than turning up later with a bigger budget.
This isn't a niche behaviour either. Around half of all AI conversations are people asking for advice or an answer, not asking AI to write or generate something. Those are exactly the moments where being the cited source matters.
SEO decides whether you make the list. AEO decides whether you're the answer.
Our AEO expertise
Why choose Castle as your AEO agency
If your pages can't be lifted cleanly and backed up independently elsewhere, the answer still gets written, just without you in it. Unlike a drop in rankings, nothing in your analytics will tell you that happened.
We've been working in search for more than 15 years, and we treat AEO as its own discipline rather than something bolted on to an SEO retainer: finding the right questions, rewriting pages so they can be lifted cleanly, and building the outside evidence that backs them up.
Because we also run GEO and traditional SEO in-house, your content only gets written once. You're not paying one team to write for readers, another for AI, and a third to sort out the difference between them.
FAQ
AEO frequently asked questions
We'll tell you which of your target questions you're currently winning and which your competitors hold, and report on what's changed since the last update. The whole thing is judged on whether you get quoted.
SEO competes for a position in a list of links. AEO competes to be the source inside a composed answer. They overlap — pages that already rank are more likely to be retrieved — but the writing differs: AEO needs self-contained answers, question-shaped headings and machine-readable structure, and it needs the same claim verifiable off-site.
They are two halves of AI search visibility. AEO is about the retrieval and citation step: being found and credited. GEO is about how your brand is represented once the answer is being generated — whether you are described accurately and recommended. We run them together, because a citation with a poor description is a wasted one.
Perplexity and Google AI Overviews show their sources, so citations are directly observable. ChatGPT and Copilot surface sources for many prompts as well. We build a fixed prompt set per client and re-test it on a schedule, so the measure is consistent even where a platform changes how it displays attribution.
First citations on lower-competition questions typically appear within four to eight weeks of the restructuring and schema work going live. Competitive comparison prompts take longer, because they depend on off-site corroboration that has to be built. Expect meaningful movement across a prompt set over three to six months.
No. AEO work concentrates on the pages that should own high-intent questions, which is usually a small set: service pages, comparisons, pricing and the questions your sales team answers most. We prioritise by prompt value rather than working through the site.
No, and nobody can — retrieval is decided by the platform per query. What we can do is remove the reasons you are not cited today: content that cannot be extracted, entities that cannot be resolved, and claims that cannot be verified. Then we measure the citation rate and keep working the gaps.
On citation frequency across the tracked prompt set, share of answer against named competitors, which page earned each mention, and the assisted conversions that follow. We connect it to enquiries rather than reporting visibility for its own sake.
Get started today
Find out which answers you're missing from
We'll test the real questions your market is asking across all major AI platforms and show you exactly who's being cited today, before you commit to anything.