From 1731fdacf24218242dbe68af86c33124ee185147 Mon Sep 17 00:00:00 2001
From: "." <oncwnuHvp1y_TkT6Meg-PU6gKA44@git.weixin.qq.com>
Date: Mon, 9 Mar 2026 00:28:59 +0800
Subject: [PATCH] fix: add try-catch around JSON.parse calls to prevent crashes
 on malformed data

The TCP data handler and child process script both called JSON.parse
without error handling. If the MCP server sends malformed or partial
JSON, the process would crash with an unhandled exception. Now
malformed lines are skipped gracefully, and the discovery response
parse gives a clear error message.
---
 index.ts | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/index.ts b/index.ts
index bba3593..6cc6487 100644
--- a/index.ts
+++ b/index.ts
@@ -85,7 +85,7 @@ client.on('data',d=>{
   buf=lines.pop()||'';
   for(const line of lines){
     if(!line.trim())continue;
-    const msg=JSON.parse(line);
+    let msg;try{msg=JSON.parse(line);}catch{continue;}
     if(msg.id===1){
       client.write(JSON.stringify({jsonrpc:'2.0',id:2,method:'tools/list',params:{}})+'\\n');
     }else if(msg.id===2){
@@ -100,7 +100,11 @@ client.on('error',e=>{process.stderr.write(e.message);process.exit(1);});
     timeout: 10_000,
     encoding: "utf-8",
   });
-  return JSON.parse(result);
+  try {
+    return JSON.parse(result);
+  } catch {
+    throw new Error(`Failed to parse MCP tool discovery response: ${result.slice(0, 200)}`);
+  }
 }
 
 /** Call an MCP tool via direct TCP connection to the DimOS server. */
@@ -140,7 +144,12 @@ async function callTool(
       buf = lines.pop() || "";
       for (const line of lines) {
         if (!line.trim()) continue;
-        const msg = JSON.parse(line);
+        let msg: { id?: number; result?: { content?: unknown }; error?: { message: string } };
+        try {
+          msg = JSON.parse(line);
+        } catch {
+          continue; // skip malformed JSON lines
+        }
         if (phase === "init" && msg.id === 1) {
           phase = "call";
           client.write(