Data & schema semantics · Naming & aliasing

x-additionalPropertiesName

`x-additionalPropertiesName` appears on schema objects and properties. Its value is a string. Used by 20 providers across 37 OpenAPI documents. Observed values include `nexset_attribute_name`, `db_column_name`, `symbol`, `locationId`. Consistent with naming & aliasing — 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.
405 occurrences
37 documents
20 providers
purpose-named

Where it appears

Location in the documentOccurrences
schema 381
response 15
parameter 2
operation 2
header 1
requestBody 2
tag 2

What its value looks like

Value shapeOccurrences
string405

Observed values

Sampled from the specifications, most frequent first.

nexset_attribute_namedb_column_namesymbollocationIdcredential_propertyfacetattributecurrency

Providers publishing it

All 20.

algoliacloudkitchenscognitecpanelemailoctopusfdc3garner-healthhitbtclawvulichesslightspeedloopiomongodbnexlaopeneopeertubesentinel-hubsinchtwiliotyro

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.