Performance & quality

x-validate

`x-validate` appears on schema objects and properties. Its value is a string. Used by a single provider across 12 OpenAPI documents. Observed values include `null`. Consistent with performance & quality — this is inferred from where the key appears and what it carries, not from any published definition.

Performance & quality 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.

3505 occurrences

12 documents

1 providers

purpose-named

Where it appears

Location in the document	Occurrences
operation	566
schema	2834
requestBody	20
response	77
header	8

What its value looks like

Value shape	Occurrences
string	3505

Observed values

Sampled from the specifications, most frequent first.

null

Providers publishing it

All 1.

knock-app

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 performance & quality job.