From 6cc5470f5eb5ff039d5a0cd0a84903371eb5246e Mon Sep 17 00:00:00 2001
From: duwenxin99 <duwenxin@google.com>
Date: Wed, 4 Feb 2026 16:23:54 -0500
Subject: [PATCH] add error formatting

---
 internal/util/errors.go | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/internal/util/errors.go b/internal/util/errors.go
index ef4f9ea6db..1f61aa1887 100644
--- a/internal/util/errors.go
+++ b/internal/util/errors.go
@@ -44,7 +44,12 @@ type AgentError struct {
 
 var _ ToolboxError = &AgentError{}
 
-func (e *AgentError) Error() string { return e.Msg }
+func (e *AgentError) Error() string {
+	if e.Cause != nil {
+		return fmt.Sprintf("%s: %v", e.Msg, e.Cause)
+	}
+	return e.Msg
+}
 
 func (e *AgentError) Category() ErrorCategory { return CategoryAgent }
 
@@ -63,7 +68,12 @@ type ClientServerError struct {
 
 var _ ToolboxError = &ClientServerError{}
 
-func (e *ClientServerError) Error() string { return fmt.Sprintf("%s: %v", e.Msg, e.Cause) }
+func (e *ClientServerError) Error() string {
+	if e.Cause != nil {
+		return fmt.Sprintf("%s: %v", e.Msg, e.Cause)
+	}
+	return e.Msg
+}
 
 func (e *ClientServerError) Category() ErrorCategory { return CategoryServer }