OAuth client list API returning blank scopes array

Problem
We’re running an audit on our org’s OAuth clients. The scopes just aren’t showing up in the payload. The admin UI displays the assignments clearly, but the REST call keeps returning empty arrays.
Code
GET /api/v2/oauth/clients
Response
{
“items”: [
{
“id”: “client-xyz”,
“scopes”:
}
]
}
The service account token definitely has oauth:client:read.