x-source-page
`x-source-page` appears on operations. Its value is a string. Used by 4 providers across 20 OpenAPI documents. Observed values include `https://developer.westernalliancebank.com/s/postman-collection`, `https://docs.thefork.io/B2B-API/API specifications/post-v-1-call-center-call-rec`, `https://docs.thefork.io/B2B-API/API specifications/get-v-1-customers-eb6`, `https://docs.thefork.io/B2B-API/API specifications/get-v-1-customers-id-11e`. Consistent with data & schema semantics — 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 | |
|---|---|---|
| operation | 69 | |
| info | 12 |
What its value looks like
| Value shape | Occurrences |
|---|---|
| string | 81 |
Observed values
Sampled from the specifications, most frequent first.
Providers publishing it
All 4.
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.