Three disciplines now claim the same website, and each asks it a different question. SEO asks whether a search engine will rank a page. GEO, generative engine optimisation, asks whether a generated answer will cite it. Agent readiness asks whether a program acting for a person can complete a task on it. The first two are about visibility. The third is about use, and a site can be highly visible and unusable at the same time.
The overlap between the three is real, and a team with good technical SEO hygiene starts with a meaningful head start on our rubric. But the overlap is confined to roughly half of the rubric, and the half it misses is the half where the commercial damage happens.
Three questions, one site
It helps to be precise about what each discipline is optimising for.
SEO optimises for position in a ranked list. The consumer is a search crawler that fetches pages, renders them in a headless browser, follows links, and feeds an index that orders results by relevance and authority. Success is relative: you are above or below a competitor.
GEO optimises for citation. The consumer is a model, or the retrieval system in front of it, assembling an answer from sources. Success is being one of the sources the answer names. It is still visibility, and still relative, but the unit is a claim rather than a page, and the signals that matter shift towards clarity, extractability and provenance.
Agent readiness optimises for task completion. The consumer is a program that has been asked to do something specific: find the price, check availability, fill in the enquiry form, compare two plans, put an item in a basket. Success is absolute. Either the task completed or it did not, and no amount of ranking compensates for a form that cannot be submitted.
Where they overlap
About half of our rubric would be recognised by any technical SEO. In pillar A, a robots.txt that parses (A1) and a valid, referenced sitemap (A3) are decades-old hygiene. In pillar B, parseable JSON-LD (B1), the right schema types for the site (B2), one h1 and sane heading order (B3), title and description lengths (B4), alt text (B6) and canonical hygiene (B7) are the standard technical audit. In pillar D, TLS (D1), lastmod freshness (D4) and consistent identity (D5) are likewise familiar.
If you have done that work properly you have already earned a good share of those pillars, and we would rather say so than pretend the disciplines are unrelated. The points are the same points. What differs is why they matter and what sits beside them.
Where SEO stops
The first divergence is rendering. The dominant search crawler renders JavaScript before indexing, and its operator documents that it does. Most agents fetch the raw HTML and do not. A site built as a client-rendered application can index perfectly and still hand an agent an empty shell. That is check A7, server-rendered content parity, five points and rated High effort, and it sits upstream of everything: schema, forms and links that only exist after hydration are, to a plain fetch, not there. The two fetches explains how it is measured.
The second is access. A robots.txt written with a search crawler in mind says nothing about GPTBot, ClaudeBot or Claude-User, and a CDN's default bot rules can refuse those user agents before robots.txt is read. Check A2 scores what the file says about six named crawlers; check A5 sends real requests under three of them and records what comes back. A site can pass every crawlability test in a search console and fail both. The field guide to AI user agents covers what each crawler is for.
The third is the nature of the score. Ranking is relative, so SEO is a contest and the result depends on who else is competing. Usability is not a contest. A form either has a labelled email input with a real submit button or it does not, and the answer is the same whether or not a competitor's form is worse.
Where GEO stops
GEO is closer to agent readiness than SEO is, and the two are often confused because they share vocabulary. Both care about llms.txt (A4). Both care about the search-index crawlers being let in. Both reward freshness signals (D4), a verifiable identity (D2) and a site name that agrees with itself across the title, og:site_name and schema (D5), because a model weighing whether to cite a source can check those things and a human reader cannot easily.
But GEO stops at citation. Its question is whether your page becomes a source in an answer. It does not ask whether a program could then do anything on the page: submit the form the answer pointed at, run the search the answer recommended, or complete the purchase the answer suggested. A site can be cited constantly and be unusable for every one of those tasks. The citation is a link, and the link leads to the same client-rendered shell, the same click-handled div navigation, the same login-gated cart.
Being cited and being usable are different properties. The first is worth having. The second is where the task actually completes, or fails silently.
What only agent readiness asks
Pillar C, actionability, has no equivalent in either discipline. Its six checks are worth 25 points, a quarter of the score, and none of them has ever been a ranking factor.
C1 asks whether every form input carries a label or aria-label, whether input types are correct (email, tel, number), and whether submit is a real button. C2 asks whether navigation uses anchor elements rather than click-handled divs, and whether fewer than 5% of links use contextless text such as "click here". C3 asks whether buttons are button elements, focusable, in a sane tab order, with no keyboard traps under render. C4 asks whether any machine endpoint exists at all, an agents.json, an MCP or WebMCP manifest, published API documentation or a discoverable OpenAPI spec. C5, for commerce sites, asks whether a product is within two clicks of the homepage, whether price and availability in schema match the page, and whether a cart or checkout path returns 200 without a login. C6 asks whether on-site search uses GET with a query parameter, so an agent can construct a search URL rather than having to drive a form.
Most of these overlap heavily with accessibility rather than with SEO. A form a screen reader can fill is a form an agent can fill, for the same reasons. If your organisation has done WCAG work, that is the team whose knowledge transfers.
The failure mode is also different. A page that drops in rankings shows up in a dashboard. An agent that cannot submit your form does not file a report. It uses a competitor it could read, and the enquiry you did not receive is not counted anywhere.
What this means for who does the work
The practical consequence is that agent readiness is not a job you can hand entirely to whoever does your SEO, and not one you can hand entirely to engineering either.
The parts that overlap with SEO, most of pillars B and D and the hygiene half of pillar A, are Low and Medium effort in the rubric and can be owned by the same people who own your search work. The rendering question in A7 and the machine endpoints in C4 are rated High effort because they are architecture, not content. The rest of pillar C is engineering work of the ordinary kind: templates, form markup, the search route. The three tiers of fixes maps the effort ratings to what the work involves, and the implementation service exists for the parts a marketing team cannot do in a CMS.
Check your own site
The free scan scores all four pillars, so you can see directly which of your points came from SEO hygiene and which are missing because nobody has ever asked the actionability question. The full definitions are on the methodology page, starting with discovery and access and continuing to actionability, the pillar the other two disciplines do not cover.