Data & schema semantics · Units & formatting

x-version-timestamp

`x-version-timestamp` appears in the info block. Its value is a string. Used by a single provider across 21 OpenAPI documents. Observed values include `2025-11-26T19:10:23Z`, `2026-05-04T17:39:21Z`, `2026-02-08T16:13:08Z`, `2026-02-12T23:38:57Z`. Consistent with units & formatting — 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.
21 occurrences
21 documents
1 providers
purpose-named

Where it appears

Location in the documentOccurrences
info 21

What its value looks like

Value shapeOccurrences
string21

Observed values

Sampled from the specifications, most frequent first.

2025-11-26T19:10:23Z2026-05-04T17:39:21Z2026-02-08T16:13:08Z2026-02-12T23:38:57Z2026-02-18T18:20:34Z2026-03-13T21:22:42Z2026-06-04T10:33:46Z2026-05-08T11:06:53Z

Providers publishing it

All 1.

elastic-path

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.