In the RAM console, you can authorize RAM users to call the following operations on an ApsaraDB for MongoDB resource.

Action CreateDBInstance ModifyNodeSpecBatch ModifySecurityGroupConfiguration
DeleteDBInstance createNodeBatch CheckCloudResourceAuthorized
CreateShardingDBInstance UpgradeDBInstanceEngineVersion DescribeUserEncryptionKeyList
ModifyNodeSpec UpgradeDBInstanceKernelVersion DescribeDBInstanceEncryptionKey
RestartDBInstance SwitchDBInstanceHA DescribeDBInstanceTDEInfo
ModifyDBInstanceDescription DestroyInstance ModifyDBInstanceTDE
DescribeReplicaSetRole DescribeDBInstancesOverview ModifyDBInstanceSSL
ModifyDBInstanceNetworkType DescribeAvailableEngineVersion DescribeDBInstanceSSL
DescribeAccounts DescribeRoleZoneInfo DescribeAuditPolicy
DescribeSecurityIps DescribeInstanceAutoRenewalAttribute ModifyAuditLogFilter
DescribeAuditRecords DescribeActiveOperationTaskCount DescribeAuditLogFilter
DescribeBackupPolicy DescribeActiveOperationTaskType ModifyAuditPolicy
CreateBackup EvaluateResource DescribeMongoDBLogConfig
RestoreDBInstance DescribeAvailableResource DescribeSlowLogRecords
DescribeDBInstances ModifyResourceGroup DescribeErrorLogRecords
ModifyDBInstanceSpec MigrateToOtherZone DescribeRunningLogRecords
RenewDBInstance MigrateAvailableZone ModifyDBInstanceMonitor
DeleteNode AllocatePublicNetworkAddress DescribeDBInstanceMonitor
CreateNode ReleasePublicNetworkAddress DescribeParameterModificationHistory
ModifyDBInstanceMaintainTime ModifyInstanceVpcAuthMode DescribeParameters
DescribeDBInstanceAttribute ModifyDBInstanceConnectionString CheckRecoveryCondition
DescribeShardingNetworkAddress ReleaseNodePrivateNetworkAddress ModifyInstanceAutoRenewalAttribute
ModifyDBInstanceNetExpireTime AllocateNodePrivateNetworkAddress TransformToPrePaid
ResetAccountPassword TagResources RenewDBInstance
ModifySecurityIps ListTagResources DescribeRenewalPrice
DescribeAuditFiles DescribeTags DescribeDBInstancePerformance
ModifyBackupPolicy UntagResources DescribeSecurityGroupConfiguration
DescribeBackups ModifyAccountDescription -

For the DescribeDBInstances operation, you must grant the permissions to call the operation on all instances. No authentication is required for the DescribeRegions operation.