diff --git a/src/judas_protocol/types.py b/src/judas_protocol/types.py
index 9dd6f03..3b4a4e0 100644
--- a/src/judas_protocol/types.py
+++ b/src/judas_protocol/types.py
@@ -5,14 +5,21 @@ from __future__ import annotations
 
 from enum import Enum
 
-type ActionType = ControlAction
+type ActionType = ControlAction | TelemetryAction
 
 
 class Category(str, Enum):
     CONTROL = "control"
+    TELEMETRY = "telemetry"
 
 
 class ControlAction(str, Enum):
     HELLO = "hello"
     ACK = "ack"
     CLOSE = "close"
+
+
+class TelemetryAction(str, Enum):
+    INITIAL = "initial"
+    UPDATE = "update"
+    ON_DEMAND = "on_demand"