Technical Explainer
How AI Search Works — RAG, Training, and What It Means for Your Brand
To optimise for AI search, you need to understand how AI search actually works. This explainer covers the mechanics — and translates them into practical implications for your brand.
Track your brand in AI searchThe difference
Traditional search vs AI search
Traditional search (Google pre-AI)
- ·Crawls and indexes pages by keyword relevance
- ·Returns a ranked list of 10 results
- ·User clicks through to find their answer
- ·Success = high ranking, high CTR
- ·Signals: backlinks, on-page keywords, page authority
- ·Optimised by: SEO — title tags, link building, content
AI search (ChatGPT, Perplexity, AI Overviews)
- ·Generates a synthesised answer from multiple sources
- ·Returns one answer — often with 2–5 citations
- ·User gets the answer without clicking
- ·Success = appearing in the answer and citations
- ·Signals: entity consistency, direct answers, schema, authority
- ·Optimised by: AEO — structured content, entity signals, schema
The two paradigms are not mutually exclusive — strong traditional SEO creates foundations that benefit AI search visibility. But AI search requires additional, specific optimisations that have no precedent in traditional SEO. A brand can rank #1 on Google and be completely invisible in ChatGPT.
The mechanics
How LLMs retrieve information
Large language models draw from three distinct information sources. Understanding each one tells you where to focus your optimisation effort.
Training data
The model's base knowledge
How it works
During pre-training, LLMs ingest vast quantities of web content — articles, documentation, forum posts, news. Brands, products, and concepts that appear frequently, consistently, and accurately in that training corpus become part of the model's base knowledge. This knowledge is static until the model is retrained.
What to do
To influence training data signals: build consistent, authoritative content published across many sources over time. Wikipedia mentions, press coverage, and well-linked documentation all contribute.
RAG (Retrieval-Augmented Generation)
Real-time web retrieval
How it works
Many modern AI systems — including Perplexity, ChatGPT with web browsing, and Google AI Overviews — use RAG: they fetch current web pages at query time, extract relevant passages, and incorporate them into the generated answer. This is more dynamic than training data and can be influenced by current on-page content.
What to do
To perform well in RAG: ensure key pages are crawlable by AI agents (check robots.txt), load fast, and contain direct answers to target questions. Structured data and clear semantic HTML improve extraction quality.
Fine-tuning and RLHF
Human preference training
How it works
Models are refined using Reinforcement Learning from Human Feedback (RLHF) — human raters evaluate responses, and the model learns to prefer answer styles that humans rate as accurate, helpful, and trustworthy. This shapes which types of content and sources the model gravitates toward.
What to do
High-quality, trustworthy, well-cited content performs better because it matches the response style RLHF training reinforces. Thin, marketing-heavy content without supporting evidence is deprioritised.
Signals
What makes a brand AI-discoverable
AI-discoverability is not random. The brands that appear consistently in AI answers share a set of common signals — most of which can be deliberately built.
Measurement
Knowing your current AI visibility
Understanding how AI search works is the first step. The second step is knowing where your brand actually stands — right now — across the AI platforms your customers use.
Without measurement, you are flying blind. You might be investing in content that AI systems never cite, missing obvious gaps that competitors have already filled, or unaware that AI is describing your product inaccurately.
- Which AI platforms mention your brand?
- How often vs competitors?
- Is the description accurate?
- Which questions do you appear in vs which ones you're absent from?
- Which of your pages are being cited?
Surfaceable answers all of these
Surfaceable is purpose-built AI visibility monitoring. We run daily automated queries across ChatGPT, Perplexity, Claude, Gemini, and Grok — giving you the data you need to understand your AI search presence and improve it systematically.
- Daily queries across 5 AI platforms
- Competitor share of voice comparison
- Answer accuracy monitoring
- Citation source tracking
- Topic coverage reports
Understand your AI search presence.
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