diff --git a/src/agents/pi-embedded-runner/anthropic-stream-wrappers.ts b/src/agents/pi-embedded-runner/anthropic-stream-wrappers.ts
index 3b91760c006..7df67acb37d 100644
--- a/src/agents/pi-embedded-runner/anthropic-stream-wrappers.ts
+++ b/src/agents/pi-embedded-runner/anthropic-stream-wrappers.ts
@@ -351,7 +351,7 @@ export function createAnthropicFastModeWrapper(
             payloadObj.service_tier = serviceTier;
           }
         }
-        return originalOnPayload?.(payload, model);
+        return originalOnPayload?.(payload);
       },
     });
   };
diff --git a/src/agents/pi-embedded-runner/openai-stream-wrappers.ts b/src/agents/pi-embedded-runner/openai-stream-wrappers.ts
index 32f998ffc46..b0be191247f 100644
--- a/src/agents/pi-embedded-runner/openai-stream-wrappers.ts
+++ b/src/agents/pi-embedded-runner/openai-stream-wrappers.ts
@@ -306,7 +306,7 @@ export function createOpenAIFastModeWrapper(baseStreamFn: StreamFn | undefined):
             model,
           });
         }
-        return originalOnPayload?.(payload, model);
+        return originalOnPayload?.(payload);
       },
     });
   };