| ClusterId | Identifies a cluster |
| ConstraintId | Identifies a constraint item on the cluster |
| ContextId | Identifies a context |
| ControllerId | Identifies Helix nodes that take on the CONTROLLER role |
| Id | Generic identifier for Helix constructs |
| MessageId | |
| ParticipantId | |
| PartitionId | |
| ProcId | |
| ResourceId | Identifies a resource |
| SessionId | |
| SpectatorId | |
| StateModelDefId | |
| StateModelFactoryId | Id representing a state model factory |