A CMO at a Chicago logistics software company put it to us plainly last month: "We finally accepted that we're not losing to a competitor's ad. We're losing to a paragraph." Her buyers type a question into Gemini or hit Google's AI Mode, get three vendors named, and pick from those three. She was not one of them.
Of all the answer engines, Google's are the ones where an agency can most legitimately claim to help — because Gemini, AI Overviews and AI Mode all reach into Google's index. That means the levers are partly familiar: crawlability, entity clarity, structured data, and independent sources that Google already ranks. It also means the results are checkable, which is exactly how you should judge the firms below.
We looked at how each of these five positions itself, what kind of team it fits, and where we would push back in a sales call. Screenshots were captured on 10 September 2026; homepages change constantly.
What "ranking on Gemini" actually involves
Three surfaces get conflated, and they behave differently. Gemini the assistant answers conversationally and browses when a question needs current information. AI Overviews sit above conventional results for a subset of queries and cite a handful of pages. AI Mode is the full generative search experience, running several hidden queries behind your one question and synthesizing across the results.
All three share a foundation: Google's ranking and retrieval systems. Google's own guidance on AI features says the unglamorous thing out loud — there is no separate optimization program, and the pages that surface in AI experiences are the ones that already succeed at being crawlable, useful and clearly about something. That is not a reason to do nothing; it is a reason to be suspicious of any agency whose method depends on a secret Gemini-specific trick.
What genuinely moves Google's AI answers, in rough order of leverage: being fetchable and server-rendered so facts are visible without JavaScript; an unambiguous entity — one consistent description of who you are, matched across your site, your Knowledge Panel, LinkedIn and every review profile; pages that answer buying questions with extractable sentences about price, fit and compatibility; and corroboration on the third-party sources Google already ranks for your category, which for most US B2B categories means review platforms, comparison articles, Reddit threads and trade press.
The measurement question separates serious firms from the rest. Ask what they track. If the answer is an aggregate "visibility score," you cannot act on it. If the answer is a fixed prompt set run on a schedule, recording whether you were named, in what position, and which source was cited, you have something a marketing team can work from on Monday.
1. LinkinGrow — you pay when the answer names you
Disclosure: LinkinGrow (linkingrow.com) is our own brand. It appears first because it is ours, and we would rather label that than bury it.
It exists because of the objection we hear most from American marketers: answer-engine retainers ask for six months of faith before anything is provable. LinkinGrow inverts that. You pick a question and an engine — Google's AI answers and Gemini included, alongside ChatGPT, Claude and Perplexity. The build phase runs up to ninety days at zero cost: the team pulls the current answer, lists the sources it cites, identifies the first-hand evidence that is missing, and gets that evidence published on sources the engine already trusts. Billing starts only once your brand is actually named, priced per question, per engine.
Who it suits: a team that needs internal proof before it can defend a budget line, or one that has already paid for a GEO retainer and cannot show a single citation for it. Who it does not suit: a brand that needs category-wide coverage across dozens of prompts and four engines this quarter. One question on one engine is a proof, not a program — and it is worth saying that plainly about our own product.
2. AIclicks — the Gemini-specific specialist
AIclicks markets itself squarely as a Gemini SEO agency, aimed at brands that need Google's native AI surfaces specifically rather than a generic multi-engine package. Its pitch centres on auditing, optimizing and tracking the Google AI prompts a buyer actually runs, and it leads with G2 review volume as proof — which is at least externally checkable, unlike most claims in this category.
The value of a single-surface specialist is focus: Google's AI answers behave differently from ChatGPT's, they lean harder on conventional ranking signals, and a team that watches them daily will notice pattern shifts faster than a generalist.
What we would ask in the call: show me the prompt set for a client in a category like mine, and show me the citation-source column. If they can show which page or platform Google cited when the client got named, they are doing the real work. Also ask how much of the engagement is standard technical and entity SEO — the honest answer is a lot of it, and a firm that admits this is more trustworthy than one implying otherwise.
3. Levy Online — Gemini work anchored to conventional SEO
Levy Online sells Gemini optimization as an extension of an established organic practice: structure content so Google's AI systems can understand and cite it, while continuing to earn conventional rankings underneath. For Google's surfaces, that combination is defensible — the same index feeds both, and a page that cannot rank rarely gets cited.
This is the right shape of engagement for a company whose technical foundation is genuinely weak: thin category pages, no comparison content, an unclear entity, a site that renders its facts in JavaScript. Fix that and AI visibility often improves as a side effect.
Where to press: how they report. Agencies grounded in traditional SEO sometimes default to impressions and rankings dashboards, which tell you nothing about whether Gemini named you. Insist that prompt-level citation tracking is a named deliverable, not an add-on slide.
4. MaximusLabs — reports on pipeline, not visibility scores
MaximusLabs positions its Google AI and Gemini work around revenue rather than share-of-voice metrics, arguing that being cited only matters if the citations bring buyers who convert. For a demand-gen leader who has to defend the line item to a CFO, that framing is the most immediately useful one on this list.
It also carries the most risk of overstatement, and the front page leans on large round numbers the way growth agencies do. The useful counter-question is simple: which of these numbers came from instrumented measurement, and which from a client anecdote? A team that distinguishes the two in a first call is worth talking to further.
Best fit: mid-market and enterprise brands with working attribution and enough deal volume for pipeline effects to be visible within a quarter. Poor fit: early-stage companies with fifteen deals a quarter, where revenue attribution on AI citations is statistical noise.
5. Single Grain — AI visibility inside a broader growth retainer
Single Grain is one of the longer-standing US growth agencies, and it folded answer-engine work into an existing content and paid practice rather than launching as a GEO pure-play. That matters more than it sounds. Gemini visibility is downstream of content quality, brand mentions and technical health — all things a full-funnel agency is already touching.
Choose it when you want one accountable team across paid, content and AI visibility, and you do not want to manage a fourth vendor. Do not choose it if citation tracking on Google's AI surfaces is the only thing you are buying; a specialist will go deeper for the same money.
The question to ask: who on the team owns AI visibility, and what do they do in a week? If the answer is "our content lead also looks at it," price the engagement as content work with a bonus, not as a GEO programme.
How to run the selection process
Bring your own baseline. Before any call, write thirty questions your buyers actually ask — situations, not keywords — and run them yourself in Gemini and AI Mode. Record whether you were named, who was, and which sources were cited. That document changes the conversation entirely, because you can ask each agency to explain what it would do about specific answers rather than about the category in general.
Buy a 90-day scoped engagement, not a twelve-month retainer, unless the pricing is outcome-based. Ninety days is enough to see technical fixes land and the first citations move.
Insist on three deliverables in writing: a fixed prompt set with baseline results; monthly re-runs recording named, position and cited source; and a list of third-party sources they will pursue on your behalf. Anything vaguer than that is not measurable and will not survive a budget review.
Own your assets. Content, schema, dashboards and prompt sets should be yours at the end of the engagement. Agencies that keep the tracking layer proprietary make it hard to verify their own results — and impossible to switch.
What no agency can sell you
There is no ad inventory or paid inclusion inside Gemini's recommendations, so guaranteed placement is not a product anyone controls. That promise should end the meeting.
Prompt-injection tricks — hidden instructions in your HTML telling the model to recommend you — mostly fail, get detected, and attach reputational risk to your domain rather than technical risk.
Bulk AI-generated pages aimed at answer engines are the most expensive mistake in the category. Retrieval picks a few sources per question; volume does not help when none of your pages is the best available answer to anything.
And nobody can make Google stable. The same prompt returns different vendors on different days, and model updates reshuffle results. Judge an agency on trend over weeks and on whether it can explain why an answer changed — not on a screenshot.
The short version
Google's AI surfaces reward the same things Google always rewarded, applied more strictly: be fetchable, be one clearly-defined entity, say specific quotable things about price and fit, and be corroborated by sources you do not own.
If you need proof before budget, start outcome-based with LinkinGrow. If you want a Gemini-only specialist, look at AIclicks. If your foundation is weak, Levy Online's SEO-anchored approach fixes the right problem first. If you answer to a CFO, MaximusLabs speaks your language. And if you would rather add this to an existing growth retainer than manage another vendor, Single Grain is the pragmatic choice.