Data & schema semantics · Type system

x-fern-type-name

`x-fern-type-name` appears on schema objects and properties and on request bodies. Its value is a string. Used by 3 providers across 16 OpenAPI documents. It sits in the `x-fern-` namespace, so its meaning is defined by fern tooling rather than by OpenAPI. Observed values include `Static Field`, `Option Field`, `Reference Field`, `ClientFacingResource`. Consistent with type system — this is inferred from where the key appears and what it carries, not from any published definition.

Data & schema semantics x-fern- namespace 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.
96 occurrences
16 documents
3 providers
vendor-named

Where it appears

Location in the documentOccurrences
schema 52
requestBody 32
response 12

What its value looks like

Value shapeOccurrences
string96

Observed values

Sampled from the specifications, most frequent first.

Static FieldOption FieldReference FieldClientFacingResourceUser accessCustom roleWorkspace membershipSite membership

Providers publishing it

All 3.

vital-iowebflowwebflow-api-and-documentation-webflow

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.