x-errorCodes
`x-errorCodes` appears on response objects. Its value is a list. Used by a single provider across 3 OpenAPI documents. 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.
1860 occurrences
3 documents
1 providers
purpose-named
Where it appears
| Location in the document | Occurrences | |
|---|---|---|
| response | 1860 |
What its value looks like
| Value shape | Occurrences |
|---|---|
| array | 1860 |
Providers publishing it
All 1.
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.