curl --request GET \
  --url https://api.natural.co/api-keys/{key_id} \
  --header 'Authorization: Bearer <token>'

{
  "data": {
    "type": "api_key",
    "id": "key_019cd360-4fd6-7bf5-a3b5-821ca7836c14",
    "attributes": {
      "api_key_prefix": "nat_live_abc123__",
      "name": "production-key",
      "scopes": [
        "payments.read",
        "payments.create"
      ],
      "environment": "production",
      "status": "ACTIVE",
      "created_at": "2026-01-04T15:30:00Z",
      "expires_at": "2026-04-04T15:30:00Z",
      "last_used_at": null,
      "revoked_at": null,
      "created_by": null,
      "revoked_by": null
    },
    "relationships": {
      "party": {
        "data": {
          "type": "party",
          "id": "pty_019cd1798d617f65a79cb965dda9eac3"
        }
      }
    }
  }
}