What schema markup do AI assistants read?

Schema.org JSON-LD, populated rather than merely present. Empty fields count for nothing.

Schema markup is a block of JSON in your page source that states facts in a form a machine can lift without interpreting your prose. For a business the useful type is LocalBusiness (or one of its subtypes), and the fields that earn their place are the ones a person would ask for: name, address, phone, hours, and what you actually do.

Populated, not present

This is the distinction most tools skip. Markup with the fields left blank passes a validator and tells an assistant nothing:

{
  "@type": "LocalBusiness",
  "name": "Joe's Pizza",
  "address": "",
  "telephone": ""
}

We count that address as missing, because a crawler cannot quote an empty string either. If you cannot fill a field in truthfully, leave it out — an omitted field is honest, an empty one is noise.

What a local business should have

name — exactly as you trade, matching your listings.
address — a full PostalAddress, not a single line of text.
telephone — in the format a customer would dial.
openingHours — the question assistants are asked most.
url and description — what you do, in a sentence.

A software company legitimately has no opening hours, and demanding them would be demanding invented facts. The right set depends on what you actually are.

Where it goes, and what breaks it

Put it in a <script type="application/ld+json"> block in the served HTML. Two things silently destroy it:

Invalid JSON. A trailing comma is enough. Crawlers discard the whole block without complaint, so a page can look marked-up and carry nothing.
Injecting it with JavaScript. If the block is added after load, the crawlers that matter here never see it.

Straight answers

JSON-LD, microdata or RDFa?

JSON-LD. It sits in one block, it does not entangle your markup, and it is what search engines recommend.

Do I need schema on every page?

No. Put business facts on the pages that carry them — home and contact — and page-specific types elsewhere only where they are true.

Will schema markup get me quoted?

It makes your facts quotable. It does not make an assistant choose you, and nothing honest promises that.

Does invalid JSON-LD hurt me?

It wastes the opportunity rather than penalising you: the block is discarded, so the page is treated as having no markup at all.

Where does your site stand? The scan is free, takes about 60 seconds, and needs no account. It fetches your homepage exactly the way GPTBot, ClaudeBot and PerplexityBot do and tells you what they receive.