What does an AEO agency do for a retainer?
A competent AEO agency sells the labour of the discipline: researching what your buyers ask AI engines, producing content built to be cited, tending your brand's facts and entity consistency across the web, fixing the technical conditions that block machine readability, and reporting how the answers moved. The deliverables look like SEO-agency deliverables, and many AEO agencies are SEO agencies that widened, which is neither praise nor criticism: the crafts overlap, and the surfaces reward different things.
What a retainer buys, structurally, is other people's hours and other people's accumulated judgement. What it costs, beyond the fee, is coordination: attention shared across a client roster, scope negotiated monthly, and category knowledge that lives with the agency. Whether that trade makes sense depends on your alternatives, which is where this guide is honest about ours: MentionOS sells the labour without the roster, and this page ends with when each makes sense.
Which six questions expose a weak AEO agency?
Ask these in the first call, in this order, and a packaging-led agency runs out of road by the third.
Where will the content live? The only good answer is your domain, in your CMS. Content published on agency-controlled properties builds their asset.
How do you decide what to produce? Strong agencies work from the questions buyers put to the engines and from measured answer gaps. Weak ones work from a content calendar that could belong to any client.
Which engines do you check, and how often? "We track ChatGPT, Gemini and Perplexity weekly, and here is the record" is the shape of a real answer. A monthly screenshot deck is a warning.
What exactly happened last month? The test of an operation is whether it can show shipped work item by item, tied to the finding that caused it. Activity summaries hide; ledgers show.
How will you measure whether any of it worked? The honest mechanism reads the answers themselves, before and after, alongside Search Console and analytics data. Deliverable counts measure effort, and effort was never the point.
What can you guarantee? The only correct answer is nothing. No agency controls what ChatGPT, Gemini or Perplexity says, and one that promises placements or mention counts has told you how it treats the truth everywhere else.
When is an agency the right call?
Genuinely, in three situations. When your organisation wants a human relationship with strategic counsel attached, someone to argue with, to educate your team, to bring judgement from other categories. When your AEO problem is entangled with larger work an agency is already doing, a rebrand, a site migration, a PR push. Or when internal politics require an external authority's name on the recommendation. Those are real values, they are what the premium over tools and software buys, and a good agency earns it. Worth knowing as you evaluate: the models are converging, and forward-leaning agencies increasingly run agent tooling inside their own delivery, pairing human judgement with software labour so clients get both.
The retainer fits worst where the buyer wants the labour itself, continuously, without the coordination overhead: the brand with no marketing team to brief an agency, review its drafts and chase its tickets. Coordinating an agency is itself a job, and companies without a person to do that job get poor value from even good agencies.
When does an agent replace the retainer?
When the thing you need is the work performed, and the strategy question is "get us into the answers" rather than a bespoke puzzle. MentionOS runs the same labour an AEO retainer covers, as software: it reads ChatGPT, Claude, Gemini, Google AI and Perplexity continuously, writes and publishes to your own site through the platform you already use, maintains product and brand facts, proposes technical fixes, and reports what moved against your Search Console and Analytics data, connected for every customer. Every consequential move is proposed for your approval first and every action keeps a receipt, which answers the show-me-last-month question by construction. There is no roster to share attention with, and what it learns about your brand accrues to your account instead of leaving with an account manager.
The broader map of every way to buy this work sits in answer engine optimization services, and if you are weighing software instead of agencies, the best rated AEO tools compares eight honestly, ours included.
FAQ
How much does an AEO agency cost?
Retainers vary too widely for a useful number here: scope, market and seniority move the figure by multiples. The better question inside any budget is what share of the fee buys performed work versus reporting about work, which the six questions above surface quickly.
Can my current SEO agency handle AEO?
Possibly, and it is worth asking before adding a vendor. The overlap is real: technical hygiene, content craft and entity work transfer. The gaps to probe are whether they read AI answers on a schedule, produce content shaped for citation, and measure inside the engines your buyers use. Put the six questions to them like any other candidate.
Is AEO worth outsourcing at all?
The work responds to consistency more than to brilliance, which argues for whoever will perform it reliably: an agency if you have the coordination capacity, an agent if you want the function owned by software under your approval, in-house if a capable marketer has genuine hours. The failure mode is the same in every wrapper: findings that nobody converts into shipped work.
What should the first month with any provider deliver?
A baseline and shipped work, no exceptions. The baseline: what the engines currently say across your buyers' questions, with sources recorded. The shipped work: at least the first content or fixes live on your domain. A first month that produces only a strategy document tells you how the rest will run.