| DarkWsClient | A concurrent, lazy DarkWS client. One instance owns one server session. |
| DarkWsClientErrorEventArgs | A background or subscriber error. |
| DarkWsClientLimitException | A bounded local request or notification queue is full. |
| DarkWsClientOptions | Settings captured when a client is constructed. |
| DarkWsConnectionException | A socket or connection lifecycle failure. |
| DarkWsProtocolException | A malformed or unsupported incoming message. |
| DarkWsResponseException | A controlled server error. Payloads are excluded from the exception message. |
| DarkWsStateChangedEventArgs | An ordered connection state transition. |
| DarkWsTimeoutException | A bounded client operation expired. |