From c326ad019da6ff2c70ec4422dde5ab04b394328a Mon Sep 17 00:00:00 2001
From: Nuno Campos <nuno@langchain.dev>
Date: Thu, 27 Jun 2024 18:10:47 -0700
Subject: [PATCH] Skip bad pending sends

---
 libs/langgraph/langgraph/pregel/__init__.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libs/langgraph/langgraph/pregel/__init__.py b/libs/langgraph/langgraph/pregel/__init__.py
index f34315966..784af417f 100644
--- a/libs/langgraph/langgraph/pregel/__init__.py
+++ b/libs/langgraph/langgraph/pregel/__init__.py
@@ -1816,6 +1816,9 @@ def _prepare_next_tasks(
     tasks: Union[list[PregelTaskDescription], list[PregelExecutableTask]] = []
     # Consume pending packets
     for packet in checkpoint["pending_sends"]:
+        if not isinstance(packet, Send):
+            logger.warn(f"Ignoring invalid packet type {type(packet)} in pending sends")
+            continue
         if for_execution:
             if node := processes[packet.node].get_node():
                 writes = deque()