From 28eaa934f3430aacd5d0151e07e8ae86274a4148 Mon Sep 17 00:00:00 2001
From: Sabiha Khan <sabihak89@gmail.com>
Date: Mon, 16 Feb 2026 16:20:55 +0530
Subject: [PATCH] fix: llm generation to annouce failed transfer call

---
 .../workflow/pipecat_engine_custom_tools.py   | 30 ++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/api/services/workflow/pipecat_engine_custom_tools.py b/api/services/workflow/pipecat_engine_custom_tools.py
index e07fb6b..e843471 100644
--- a/api/services/workflow/pipecat_engine_custom_tools.py
+++ b/api/services/workflow/pipecat_engine_custom_tools.py
@@ -494,6 +494,7 @@ class CustomToolManager:
         """Handle different transfer call outcomes and take appropriate action."""
         action = result.get("action", "")
         status = result.get("status", "")
+        message = result.get("message", "")
 
         logger.info(f"Handling transfer result: action={action}, status={status}")
 
@@ -527,13 +528,40 @@ class CustomToolManager:
             reason = result.get("reason", "unknown")
             logger.info(f"Transfer failed ({reason}), informing user")
 
+            from pipecat.frames.frames import LLMMessagesAppendFrame
+
+            # Create system message with clear instructions for transfer failure
+            failure_instruction = {
+                "role": "system",
+                "content": f"IMPORTANT: The transfer call has FAILED. Reason: {reason}. You must inform the customer about this failure using this message: '{message}' Then immediately say goodbye and end the conversation. Do NOT ask if they need anything else or continue the conversation. Do NOT continue with transfer language.",
+            }
+            logger.info(f"Transfer failed ({reason}), informing user")
+
+            # Push the system message to LLM context
+            await self._engine.task.queue_frame(
+                LLMMessagesAppendFrame([failure_instruction], run_llm=True)
+            )
+
+            # Send function call result - LLM will be triggered by system message
+            response_properties = FunctionCallResultProperties(run_llm=False)
             await function_call_params.result_callback(
                 {
                     "status": "transfer_failed",
                     "reason": reason,
                     "message": "Transfer failed",
-                }
+                },
+                properties=response_properties,
             )
+
+            # Schedule call end after 5 seconds to allow LLM to speak
+            async def delayed_end_call():
+                await asyncio.sleep(5)
+                await self._engine.end_call_with_reason(
+                    EndTaskReason.TRANSFER_CALL_FAILED.value, abort_immediately=False
+                )
+
+            # Create task to end call asynchronously
+            asyncio.create_task(delayed_end_call())
         else:
             # Unknown action, treat as generic success
             logger.warning(f"Unknown transfer action: {action}, treating as success")