Data & schema semantics

x-standard

`x-standard` appears in the info block. Its value is a string. Used by 6 providers across 16 OpenAPI documents. Observed values include `OAI-PMH 2.0`, `SAML 2.0 metadata (OASIS) / Shibboleth`, `oai-pmh`, `IIIF Image API 3.0, compliance level 0`. 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.
16 occurrences
16 documents
6 providers
purpose-named

Where it appears

Location in the documentOccurrences
info 16

What its value looks like

Value shapeOccurrences
object1
string15

Observed values

Sampled from the specifications, most frequent first.

OAI-PMH 2.0SAML 2.0 metadata (OASIS) / Shibbolethoai-pmhIIIF Image API 3.0, compliance level 0OAI-PMH 2.0 (http://www.openarchives.org/OAI/openarchivesprotocol.html)https://www.openarchives.org/OAI/openarchivesprotocol.htmlFDX

Providers publishing it

All 6.

anupolitecnico-di-milanoqutregions-financialuniversity-of-leedsuniversity-of-oxford

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.