diff --git a/src/pipecat/services/xai/realtime/llm.py b/src/pipecat/services/xai/realtime/llm.py
index 8b8e0d94a..7ac83d071 100644
--- a/src/pipecat/services/xai/realtime/llm.py
+++ b/src/pipecat/services/xai/realtime/llm.py
@@ -942,12 +942,19 @@ class GrokRealtimeLLMService(LLMService[GrokRealtimeLLMAdapter]):
                         error_msg="Grok Realtime does not support streamed async tool results.",
                     )
                     continue
-                # kind == "final": deliver via the formal tool-result channel
-                # — same path as a synchronous tool result, just delayed.
-                if send_new_results:
-                    sent_new_result = True
-                    await self._send_tool_result(async_payload.tool_call_id, async_payload.result)
-                self._completed_tool_calls.add(async_payload.tool_call_id)
+                if async_payload.kind == "final":
+                    # Deliver via the formal tool-result channel — same path
+                    # as a synchronous tool result, just delayed.
+                    if send_new_results:
+                        sent_new_result = True
+                        await self._send_tool_result(
+                            async_payload.tool_call_id, async_payload.result
+                        )
+                    self._completed_tool_calls.add(async_payload.tool_call_id)
+                    continue
+                # Defensive: any async-tool message must not fall through
+                # to the regular tool-result block below, even if it
+                # carries a kind we don't recognize.
                 continue
 
             # Look for newly-completed "regular" (as opposed to async-tool) results