`x-evidence` appears on operations and in the info block. Its value is a structured object. Used by 47 providers across 500 OpenAPI documents. Consistent with data & schema semantics — this is inferred from where the key appears and what it carries, not from any published definition.
Data & schema semanticsderived 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.
1198 occurrences
500 documents
47 providers
purpose-named
Where it appears
Location in the document
Occurrences
operation
686
info
468
root
44
What its value looks like
Value shape
Occurrences
object
678
array
491
string
29
Observed values
Sampled from the specifications, most frequent first.
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.