debug: write gemini raw response to disk-backed /tmp/last_gemini.json for accurate multinode diagnostics

vibn-frontend/app/api/chat/debug/route.ts

@@ -1,14 +1,26 @@
-import { NextResponse } from 'next/server';
+import { NextResponse } from "next/server";
+import fs from "fs";
+import path from "path";
 
-// Global variable to store the last raw Gemini response for easy debugging
-let lastGeminiResponse: any = null;
-
-export function setLastGeminiResponse(resp: any) {
-  lastGeminiResponse = resp;
-}
+const DEBUG_FILE = "/tmp/last_gemini.json";
 
 export async function GET() {
+  try {
+    if (fs.existsSync(DEBUG_FILE)) {
+      const raw = fs.readFileSync(DEBUG_FILE, "utf8");
+      return NextResponse.json({
+        lastResponse: JSON.parse(raw),
+      });
+    }
+  } catch (e) {
+    return NextResponse.json({
+      error: "Failed to read debug file",
+      details: String(e),
+    });
+  }
+
   return NextResponse.json({
-    lastResponse: lastGeminiResponse || "No requests captured yet since last deploy. Send a message from the desktop first."
+    lastResponse:
+      "No requests captured on disk yet since last deploy. Send a message from the desktop first.",
   });
 }

vibn-frontend/lib/ai/gemini-chat.ts

@@ -1,4 +1,5 @@
 import { GoogleGenAI } from "@google/genai";
+import fs from "fs";
 
 const GEMINI_API_KEY = process.env.GOOGLE_API_KEY || "";
 const GEMINI_MODEL = process.env.VIBN_CHAT_MODEL || "gemini-3.1-pro-preview";
@@ -139,11 +140,13 @@ export async function callGeminiChat(opts: {
     );
 
     try {
-      const { setLastGeminiResponse } =
-        await import("../../app/api/chat/debug/route");
-      setLastGeminiResponse(response);
+      fs.writeFileSync(
+        "/tmp/last_gemini.json",
+        JSON.stringify(response, null, 2),
+        "utf8",
+      );
     } catch (e) {
-      console.warn("Failed to set debug response:", e);
+      console.warn("Failed to write debug response to disk:", e);
     }
 
     let text = "";