x-additional-info
`x-additional-info` appears on schema objects and properties. Its value is a string. Used by a single provider across 3 OpenAPI documents. Observed values include `\r\n
\r\n
\r\n
\r\n Available values for t`, `\r\n
\r\n
\r\n Available values `, `\r\n
\r\n
\r\n Available v`. Consistent with size & shape — this is inferred from where the key appears and what it carries, not from any published definition.
Where it appears
| Location in the document | Occurrences | |
|---|---|---|
| schema | 20 |
What its value looks like
| Value shape | Occurrences |
|---|---|
| string | 20 |
Observed values
Sampled from the specifications, most frequent first.
\r\n
\r\n Available value
\r\n\r\n
\r\n Available values for t
\r\n\r\n
\r\n Available values
\r\n\r\n
\r\n Available v
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 data & schema semantics job.