curl --request GET \
  --url https://{host}/v2/workspaces/slug:agent-factory/webhooks/v1/agents/{agentId}/retention \
  --header 'Authorization: Bearer <token>'

{
  "policy": {},
  "effective": {
    "conversations_retention_days": 123,
    "documents_retention_days": 123,
    "tasks_retention_days": 123,
    "artifacts_retention_days": 123
  }
}