x-summary

`x-summary` appears on response objects. Its value is a string. Used by 19 providers across 77 OpenAPI documents. Observed values include `Success`, `Unauthorized`, `Internal server error`, `Not found`. Consistent with documentation & dx — this is inferred from where the key appears and what it carries, not from any published definition.

Documentation & DX 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.
2142 occurrences
77 documents
19 providers
purpose-named

Where it appears

Location in the documentOccurrences
response 1993
header 1
path 111
securityScheme 9
info 20
operation 5
root 3

What its value looks like

Value shapeOccurrences
string2127
object10
empty5

Observed values

Sampled from the specifications, most frequent first.

SuccessUnauthorizedInternal server errorNot foundService unavailableOKBad requestForbidden

Providers publishing it

All 19.

adobe-launchadobe-suiteaffindaalloy-comcms-govconfluentconfluent-the-data-streaming-platformhetznerledgermodepagopapalo-alto-networkspayupeertuberesponsysshowpadtransuniontui-groupwebhook-relay

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 documentation & dx job.