From 60f885e1eb7ca49cc1fed887b535b2c2f7d5f898 Mon Sep 17 00:00:00 2001
From: Taksh Pratap Singh <taksh001@gmail.com>
Date: Fri, 14 Nov 2025 15:56:36 -0500
Subject: [PATCH] Improve error message with JSON.stringify

---
 modal-js/src/sandbox.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modal-js/src/sandbox.ts b/modal-js/src/sandbox.ts
index 1f9961ec..6810d151 100644
--- a/modal-js/src/sandbox.ts
+++ b/modal-js/src/sandbox.ts
@@ -764,7 +764,7 @@ export class Sandbox {
       }
       if (resp.taskResult) {
         throw new Error(
-          `Sandbox ${this.sandboxId} has already completed with result: ${resp.taskResult}`,
+          `Sandbox ${this.sandboxId} has already completed with result: ${JSON.stringify(resp.taskResult)}`,
         );
       }
       this.#taskId = resp.taskId;