The AI search vocabulary, defined plainly.

AEO (Answer Engine Optimization)

Answer engine optimization is the practice of making a business the answer AI assistants give, rather than one result among ten blue links. It optimizes the signals assistants weigh when they compose an answer: entity clarity, reviews, structured data, third-party corroboration, and content direct enough to quote.

Go deeper: AEO vs SEO

GEO (Generative Engine Optimization)

Generative engine optimization is a near-synonym of AEO used when the emphasis is on generative systems like ChatGPT, Gemini, and Perplexity composing original answers. The work is the same: make a business easy for a model to find, verify, and confidently include in a generated recommendation.

AI visibility score

An AI visibility score is a 0 to 100 measure of how often AI assistants name a business when buyers ask who to hire. Sightline's version runs a fixed panel of buyer prompts, records who is named, and weights the site and reputation signals behind those answers.

Go deeper: How to read yours

Share of voice

Share of voice is the portion of AI answers that name a given business across a tracked set of prompts, measured against the competitors you name. If assistants answer a buying question twelve times and name you three, your share of voice for that panel is a quarter.

Buyer prompt

A buyer prompt is the literal question a customer asks an AI assistant when they are ready to choose a provider, like who is the best HVAC company near me. Tracking a fixed panel of these prompts month over month is how AI visibility becomes measurable instead of anecdotal.

Answer engine

An answer engine is any system that responds to a question with a composed answer instead of a list of links: ChatGPT, Claude, Perplexity, Gemini, Google AI Overviews, and Copilot all qualify. Being one of the few names inside the answer is the new version of ranking.

Entity authority

Entity authority is how confidently an AI system can identify who a business is, where it operates, and what it does, based on agreement across its website, profiles, reviews, and independent mentions. Assistants recommend businesses they are sure about; contradictions between sources quietly remove you from answers.

Go deeper: Entity authority basics

Structured data (JSON-LD)

Structured data is machine-readable markup, usually JSON-LD using schema.org vocabulary, that states a site's facts in a format engines parse directly: name, services, area served, prices, FAQs. It lets AI confirm facts instead of inferring them from prose, which makes every other signal more legible.

Citation

A citation is an independent mention of a business that AI systems can find and weigh: a directory listing, a roundup, a news mention, a review platform profile. Citations corroborate what a business says about itself, and corroboration is what turns a claim into something an assistant will repeat.

Go deeper: How citation building works

NAP consistency

NAP consistency means a business's name, address, and phone number appear identically everywhere they are published. Inconsistent listings read to machines as possibly different businesses, which fragments the entity and weakens every downstream signal, from local rankings to AI recommendations.

llms.txt

llms.txt is a plain-text file at a site's root that gives AI systems a curated orientation: what the business is, its key pages, and its facts, in prose a model can read in one pass. It complements robots.txt (permissions) and structured data (machine-readable facts).

Go deeper: llms.txt, explained

Google AI Overviews

AI Overviews are the generated summaries Google places above traditional results for many searches, composed from sources its systems consider reliable. For local services they often name specific providers, which makes the signals behind that selection part of the same visibility work as chat assistants.