x-version

`x-version` appears on operations. Its value is a string. Used by 42 providers across 42 OpenAPI documents. Observed values include `2`, `1`, `3`, `5`. 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.
764 occurrences
42 documents
42 providers
purpose-named

Where it appears

Location in the documentOccurrences
operation 760
schema 3
info 1

What its value looks like

Value shapeOccurrences
string764

Observed values

Sampled from the specifications, most frequent first.

213571.0.0v1

Providers publishing it

All 42.

alex-bankamp-bankanzaustralian-military-bankauswide-bankbank-firstbank-of-queenslandbank-of-sydneybank-of-usbanksabankwestbcu-bankbendigo-and-adelaide-bankbeyond-bankdefence-bankgateway-bankgc-mutual-bankgreat-southern-bankgreater-bankhsbc-australiahume-bankibm-quantumimb-banking-australiajudo-bankmacquarie-bankmystate-banknational-australia-banknewcastle-permanentpeople-first-bankpn-bankpolice-bankqudos-bankrabobank-australiaracq-bankregional-australia-bankspotdraftsuncorp-bankteachers-mutual-bankubankunity-bankwestpac

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.