diff --git a/google/genai/_interactions/types/error_event.py b/google/genai/_interactions/types/error_event.py
index 8abf8ca3e..f2edef4a6 100644
--- a/google/genai/_interactions/types/error_event.py
+++ b/google/genai/_interactions/types/error_event.py
@@ -18,9 +18,10 @@
 from typing import Optional
 from typing_extensions import Literal
 
+from .usage import Usage
 from .._models import BaseModel
 
-__all__ = ["ErrorEvent", "Error"]
+__all__ = ["ErrorEvent", "Error", "Metadata"]
 
 
 class Error(BaseModel):
@@ -33,6 +34,13 @@ class Error(BaseModel):
     """A human-readable error message."""
 
 
+class Metadata(BaseModel):
+    """Optional metadata accompanying ANY streamed event."""
+
+    usage: Optional[Usage] = None
+    """Statistics on the interaction request's token usage."""
+
+
 class ErrorEvent(BaseModel):
     event_type: Literal["error"]
 
@@ -43,3 +51,6 @@ class ErrorEvent(BaseModel):
     """
     The event_id token to be used to resume the interaction stream, from this event.
     """
+
+    metadata: Optional[Metadata] = None
+    """Optional metadata accompanying ANY streamed event."""
diff --git a/google/genai/_interactions/types/interaction_completed_event.py b/google/genai/_interactions/types/interaction_completed_event.py
index f19bcc50e..5a052b408 100644
--- a/google/genai/_interactions/types/interaction_completed_event.py
+++ b/google/genai/_interactions/types/interaction_completed_event.py
@@ -18,10 +18,18 @@
 from typing import Optional
 from typing_extensions import Literal
 
+from .usage import Usage
 from .._models import BaseModel
 from .interaction import Interaction
 
-__all__ = ["InteractionCompletedEvent"]
+__all__ = ["InteractionCompletedEvent", "Metadata"]
+
+
+class Metadata(BaseModel):
+    """Optional metadata accompanying ANY streamed event."""
+
+    usage: Optional[Usage] = None
+    """Statistics on the interaction request's token usage."""
 
 
 class InteractionCompletedEvent(BaseModel):
@@ -38,3 +46,6 @@ class InteractionCompletedEvent(BaseModel):
     """
     The event_id token to be used to resume the interaction stream, from this event.
     """
+
+    metadata: Optional[Metadata] = None
+    """Optional metadata accompanying ANY streamed event."""
diff --git a/google/genai/_interactions/types/interaction_created_event.py b/google/genai/_interactions/types/interaction_created_event.py
index 826ac3232..1a12a1962 100644
--- a/google/genai/_interactions/types/interaction_created_event.py
+++ b/google/genai/_interactions/types/interaction_created_event.py
@@ -18,10 +18,18 @@
 from typing import Optional
 from typing_extensions import Literal
 
+from .usage import Usage
 from .._models import BaseModel
 from .interaction import Interaction
 
-__all__ = ["InteractionCreatedEvent"]
+__all__ = ["InteractionCreatedEvent", "Metadata"]
+
+
+class Metadata(BaseModel):
+    """Optional metadata accompanying ANY streamed event."""
+
+    usage: Optional[Usage] = None
+    """Statistics on the interaction request's token usage."""
 
 
 class InteractionCreatedEvent(BaseModel):
@@ -34,3 +42,6 @@ class InteractionCreatedEvent(BaseModel):
     """
     The event_id token to be used to resume the interaction stream, from this event.
     """
+
+    metadata: Optional[Metadata] = None
+    """Optional metadata accompanying ANY streamed event."""
diff --git a/google/genai/_interactions/types/interaction_status_update.py b/google/genai/_interactions/types/interaction_status_update.py
index 877514285..b496de250 100644
--- a/google/genai/_interactions/types/interaction_status_update.py
+++ b/google/genai/_interactions/types/interaction_status_update.py
@@ -18,9 +18,17 @@
 from typing import Optional
 from typing_extensions import Literal
 
+from .usage import Usage
 from .._models import BaseModel
 
-__all__ = ["InteractionStatusUpdate"]
+__all__ = ["InteractionStatusUpdate", "Metadata"]
+
+
+class Metadata(BaseModel):
+    """Optional metadata accompanying ANY streamed event."""
+
+    usage: Optional[Usage] = None
+    """Statistics on the interaction request's token usage."""
 
 
 class InteractionStatusUpdate(BaseModel):
@@ -36,3 +44,6 @@ class InteractionStatusUpdate(BaseModel):
     """
     The event_id token to be used to resume the interaction stream, from this event.
     """
+
+    metadata: Optional[Metadata] = None
+    """Optional metadata accompanying ANY streamed event."""
diff --git a/google/genai/_interactions/types/step_delta.py b/google/genai/_interactions/types/step_delta.py
index 5d3f65cb0..fe05532d4 100644
--- a/google/genai/_interactions/types/step_delta.py
+++ b/google/genai/_interactions/types/step_delta.py
@@ -18,6 +18,7 @@
 from typing import Dict, List, Union, Optional
 from typing_extensions import Literal, Annotated, TypeAlias
 
+from .usage import Usage
 from .._utils import PropertyInfo
 from .._models import BaseModel
 from .annotation import Annotation
@@ -59,6 +60,7 @@
     "DeltaGoogleMapsResult",
     "DeltaFunctionResult",
     "DeltaFunctionResultResultFunctionResultSubcontentList",
+    "Metadata",
 ]
 
 
@@ -361,6 +363,13 @@ class DeltaFunctionResult(BaseModel):
 ]
 
 
+class Metadata(BaseModel):
+    """Optional metadata accompanying ANY streamed event."""
+
+    usage: Optional[Usage] = None
+    """Statistics on the interaction request's token usage."""
+
+
 class StepDelta(BaseModel):
     delta: Delta
 
@@ -372,3 +381,6 @@ class StepDelta(BaseModel):
     """
     The event_id token to be used to resume the interaction stream, from this event.
     """
+
+    metadata: Optional[Metadata] = None
+    """Optional metadata accompanying ANY streamed event."""
diff --git a/google/genai/_interactions/types/step_start.py b/google/genai/_interactions/types/step_start.py
index e82fa0e8f..98722ec96 100644
--- a/google/genai/_interactions/types/step_start.py
+++ b/google/genai/_interactions/types/step_start.py
@@ -19,9 +19,17 @@
 from typing_extensions import Literal
 
 from .step import Step
+from .usage import Usage
 from .._models import BaseModel
 
-__all__ = ["StepStart"]
+__all__ = ["StepStart", "Metadata"]
+
+
+class Metadata(BaseModel):
+    """Optional metadata accompanying ANY streamed event."""
+
+    usage: Optional[Usage] = None
+    """Statistics on the interaction request's token usage."""
 
 
 class StepStart(BaseModel):
@@ -36,3 +44,6 @@ class StepStart(BaseModel):
     """
     The event_id token to be used to resume the interaction stream, from this event.
     """
+
+    metadata: Optional[Metadata] = None
+    """Optional metadata accompanying ANY streamed event."""
diff --git a/google/genai/_interactions/types/step_stop.py b/google/genai/_interactions/types/step_stop.py
index b0c49d7a8..2170cc6eb 100644
--- a/google/genai/_interactions/types/step_stop.py
+++ b/google/genai/_interactions/types/step_stop.py
@@ -18,9 +18,17 @@
 from typing import Optional
 from typing_extensions import Literal
 
+from .usage import Usage
 from .._models import BaseModel
 
-__all__ = ["StepStop"]
+__all__ = ["StepStop", "Metadata"]
+
+
+class Metadata(BaseModel):
+    """Optional metadata accompanying ANY streamed event."""
+
+    usage: Optional[Usage] = None
+    """Statistics on the interaction request's token usage."""
 
 
 class StepStop(BaseModel):
@@ -32,3 +40,6 @@ class StepStop(BaseModel):
     """
     The event_id token to be used to resume the interaction stream, from this event.
     """
+
+    metadata: Optional[Metadata] = None
+    """Optional metadata accompanying ANY streamed event."""