Data & schema semantics · Mutability & access

x-derived-on

`x-derived-on` appears in the info block. Its value is a string. Used by 22 providers across 24 OpenAPI documents. Observed values include `2026-08-02`, `2026-08-04`, `2026-08-05`, `2026-08-09`. Consistent with mutability & access — this is inferred from where the key appears and what it carries, not from any published definition.

Data & schema semantics 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.
24 occurrences
24 documents
22 providers
purpose-named

Where it appears

Location in the documentOccurrences
info 24

What its value looks like

Value shapeOccurrences
string24

Observed values

Sampled from the specifications, most frequent first.

2026-08-022026-08-042026-08-052026-08-092026-08-122026-08-072026-08-08

Providers publishing it

All 22.

a2-biotherapeuticsabcuroascend-elementsatsena-therapeuticsbioflyteboundless-biocellaritycolossal-biosciencescolossal-laboratories--biosciencesdalcor-pharmaceuticalseffect-photonicsenveda-biosciencesethyreal-bioisports-apilifeminelivekindlyorionis-biosciencesskydance-mediastrata-oncologyturntide-technologiesvestaronwugen

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 data & schema semantics job.