Data & schema semantics

x-properties

`x-properties` appears on operations and in the document. Its value is a structured object. Used by 2 providers across 129 OpenAPI documents. Consistent with data & schema semantics — this is inferred from where the key appears and what it carries, not from any published definition.

Data & schema semantics derived description

How this description was produced. It is assembled from what was measured in the corpus — where this key appears in a document, what shape its value takes, the values observed, and how many providers use it. It is not taken from a published definition, because for most extensions none exists. Read it as evidence, not as a specification. If you own this extension and want it described properly, tell us.

346 occurrences

129 documents

2 providers

purpose-named

Where it appears

Location in the document	Occurrences
other	126
root	4
operation	216

What its value looks like

Value shape	Occurrences
object	342
string	4

Observed values

Sampled from the specifications, most frequent first.

null

Providers publishing it

All 2.

oracle salesflare

Why this is not in OpenAPI

Extensions exist because a provider needed something the specification would not carry. Most of what they hold is not the API contract at all — it is operational metadata about the contract: documentation, lifecycle, policy, provenance, and now agents. That metadata is usually better placed alongside the contract, in an Overlay or an APIs.json index, than crammed inside it. See everything else doing the data & schema semantics job.