feat: add toggleable tool source diagnostics

src/app/(dashboard)/dashboard/profile/page.js

@@ -462,6 +462,21 @@ export default function ProfilePage() {
     }
   };
 
+  const updateLogToolSources = async (enabled) => {
+    try {
+      const res = await fetch("/api/settings", {
+        method: "PATCH",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ logToolSources: enabled }),
+      });
+      if (res.ok) {
+        setSettings(prev => ({ ...prev, logToolSources: enabled }));
+      }
+    } catch (err) {
+      console.error("Failed to update logToolSources:", err);
+    }
+  };
+
   const reloadSettings = async () => {
     try {
       const res = await fetch("/api/settings");
@@ -553,6 +568,7 @@ export default function ProfilePage() {
   };
 
   const observabilityEnabled = settings.enableObservability === true;
+  const logToolSourcesEnabled = settings.logToolSources === true;
 
   const handleShutdown = async () => {
     setIsShuttingDown(true);
@@ -1089,18 +1105,34 @@ export default function ProfilePage() {
             </div>
             <h3 className="text-base sm:text-lg font-semibold">Observability</h3>
           </div>
-          <div className="flex items-start sm:items-center justify-between gap-4">
-            <div className="flex-1 min-w-0">
-              <p className="font-medium text-sm sm:text-base">Enable Observability</p>
-              <p className="text-xs sm:text-sm text-text-muted">
-                Record request details for inspection in the logs view
-              </p>
+          <div className="flex flex-col gap-4">
+            <div className="flex items-start sm:items-center justify-between gap-4">
+              <div className="flex-1 min-w-0">
+                <p className="font-medium text-sm sm:text-base">Enable Observability</p>
+                <p className="text-xs sm:text-sm text-text-muted">
+                  Record request details for inspection in the logs view
+                </p>
+              </div>
+              <Toggle
+                checked={observabilityEnabled}
+                onChange={updateObservabilityEnabled}
+                disabled={loading}
+              />
+            </div>
+
+            <div className="flex items-start sm:items-center justify-between gap-4 pt-4 border-t border-border/50">
+              <div className="flex-1 min-w-0">
+                <p className="font-medium text-sm sm:text-base">Log Tool Sources</p>
+                <p className="text-xs sm:text-sm text-text-muted">
+                  Add a diagnostic [TOOLS] line with tool names and MCP/source counts for each request
+                </p>
+              </div>
+              <Toggle
+                checked={logToolSourcesEnabled}
+                onChange={updateLogToolSources}
+                disabled={loading}
+              />
             </div>
-            <Toggle
-              checked={observabilityEnabled}
-              onChange={updateObservabilityEnabled}
-              disabled={loading}
-            />
           </div>
         </Card>
 

src/lib/db/repos/settingsRepo.js

@@ -24,6 +24,7 @@ const DEFAULT_SETTINGS = {
   oidcScopes: "openid profile email",
   oidcLoginLabel: "Sign in with OIDC",
   enableObservability: true,
+  logToolSources: false,
   observabilityMaxRecords: 1000,
   observabilityBatchSize: 20,
   observabilityFlushIntervalMs: 5000,

src/sse/handlers/chat.js

@@ -20,6 +20,52 @@ import * as log from "../utils/logger.js";
 import { updateProviderCredentials, checkAndRefreshToken } from "../services/tokenRefresh.js";
 import { getProjectIdForConnection } from "open-sse/services/projectId.js";
 
+function getToolName(tool) {
+  return tool?.name || tool?.function?.name || tool?.type || "unknown";
+}
+
+function getToolSource(name) {
+  if (name.startsWith("mcp__")) {
+    const parts = name.split("__");
+    return parts[1] ? `mcp:${parts[1]}` : "mcp";
+  }
+  if (name.startsWith("web_search") || name.startsWith("web_fetch")) return "hosted:web";
+  if (name.startsWith("computer_") || name.startsWith("str_replace_")) return "hosted:computer";
+  return "client";
+}
+
+function summarizeToolSources(tools) {
+  if (!Array.isArray(tools) || tools.length === 0) return null;
+  const names = tools.map(getToolName);
+  const sourceCounts = new Map();
+  for (const name of names) {
+    const source = getToolSource(name);
+    sourceCounts.set(source, (sourceCounts.get(source) || 0) + 1);
+  }
+  const sources = Array.from(sourceCounts.entries())
+    .map(([source, count]) => `${source}=${count}`)
+    .join(", ");
+  const visibleNames = names.slice(0, 80).join(", ");
+  const suffix = names.length > 80 ? `, ... +${names.length - 80} more` : "";
+  return `${tools.length} tools | sources: ${sources} | names: ${visibleNames}${suffix}`;
+}
+
+function isDeterministicPayloadError(status, errorText) {
+  if (status !== HTTP_STATUS.BAD_REQUEST) return false;
+  const text = typeof errorText === "string" ? errorText.toLowerCase() : "";
+  return text.includes("content_length_exceeds_threshold") ||
+    text.includes("input is too long") ||
+    text.includes("context length") ||
+    text.includes("maximum context") ||
+    text.includes("too many tokens");
+}
+
+function isNonAccountRecoverableError(provider, status, errorText) {
+  if (isDeterministicPayloadError(status, errorText)) return true;
+  const text = typeof errorText === "string" ? errorText.toLowerCase() : "";
+  return provider === "nvidia" && status === HTTP_STATUS.BAD_GATEWAY && text.includes("fetch connect timeout");
+}
+
 /**
  * Handle chat completion request
  * Supports: OpenAI, Claude, Gemini, OpenAI Responses API formats
@@ -67,6 +113,11 @@ export async function handleChat(request, clientRawRequest = null) {
 
   // Enforce API key if enabled in settings
   const settings = await getSettings();
+  if (settings.logToolSources === true) {
+    const toolSummary = summarizeToolSources(body.tools);
+    if (toolSummary) log.debug("TOOLS", toolSummary);
+  }
+
   if (settings.requireApiKey) {
     if (!apiKey) {
       log.warn("AUTH", "Missing API key (requireApiKey=true)");