x-namespaced-enum

`x-namespaced-enum` appears on schema objects and properties. Its value is a list. Used by 3 providers across 9 OpenAPI documents. Consistent with sdk & code generation — this is inferred from where the key appears and what it carries, not from any published definition.

SDK & code generation 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.
82 occurrences
9 documents
3 providers
purpose-named

Where it appears

Location in the documentOccurrences
schema 82

What its value looks like

Value shapeOccurrences
array82

Providers publishing it

All 3.

natwestopen-banking-ukzopa

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 sdk & code generation job.