diff --git a/internal/agent/loop.go b/internal/agent/loop.go
index 69f72749..86744794 100644
--- a/internal/agent/loop.go
+++ b/internal/agent/loop.go
@@ -1193,6 +1193,7 @@ func (l *Loop) runLoop(ctx context.Context, req RunRequest) (*RunResult, error)
 					Role:       "tool",
 					Content:    r.result.ForLLM,
 					ToolCallID: r.tc.ID,
+					IsError:    r.result.IsError,
 				}
 				messages = append(messages, toolMsg)
 				pendingMsgs = append(pendingMsgs, toolMsg)