Merge pull request #311 from olaservo/bump-version-0-9-0

Bump version to 0.9.0

CONTRIBUTING.md

@@ -7,13 +7,13 @@ Thanks for your interest in contributing! This guide explains how to get involve
 1. Fork the repository and clone it locally
 2. Install dependencies with `npm install`
 3. Run `npm run dev` to start both client and server in development mode
-4. Use the web UI at http://localhost:5173 to interact with the inspector
+4. Use the web UI at http://127.0.0.1:6274 to interact with the inspector
 
 ## Development Process & Pull Requests
 
 1. Create a new branch for your changes
-2. Make your changes following existing code style and conventions
-3. Test changes locally
+2. Make your changes following existing code style and conventions. You can run `npm run prettier-check` and `npm run prettier-fix` as applicable.
+3. Test changes locally by running `npm test`
 4. Update documentation as needed
 5. Use clear commit messages explaining your changes
 6. Verify all changes work as expected

README.md

@@ -2,7 +2,7 @@
 
 The MCP inspector is a developer tool for testing and debugging MCP servers.
 
-![MCP Inspector Screenshot](mcp-inspector.png)
+![MCP Inspector Screenshot](https://raw.githubusercontent.com/modelcontextprotocol/inspector/main/mcp-inspector.png)
 
 ## Running the Inspector
 
@@ -30,7 +30,7 @@ npx @modelcontextprotocol/inspector -e KEY=value -e KEY2=$VALUE2 node build/inde
 npx @modelcontextprotocol/inspector -e KEY=$VALUE -- node build/index.js -e server-flag
 ```
 
-The inspector runs both a client UI (default port 5173) and an MCP proxy server (default port 3000). Open the client UI in your browser to use the inspector. You can customize the ports if needed:
+The inspector runs both an MCP Inspector (MCPI) client UI (default port 6274) and an MCP Proxy (MCPP) server (default port 6277). Open the MCPI client UI in your browser to use the inspector. (These ports are derived from the T9 dialpad mapping of MCPI and MCPP respectively, as a mnemonic). You can customize the ports if needed:
 
 ```bash
 CLIENT_PORT=8080 SERVER_PORT=9000 npx @modelcontextprotocol/inspector node build/index.js
@@ -42,6 +42,23 @@ For more details on ways to use the inspector, see the [Inspector section of the
 
 The inspector supports bearer token authentication for SSE connections. Enter your token in the UI when connecting to an MCP server, and it will be sent in the Authorization header.
 
+### Security Considerations
+
+The MCP Inspector includes a proxy server that can run and communicate with local MCP processes. The proxy server should not be exposed to untrusted networks as it has permissions to spawn local processes and can connect to any specified MCP server.
+
+### Configuration
+
+The MCP Inspector supports the following configuration settings. To change them, click on the `Configuration` button in the MCP Inspector UI:
+
+| Setting                                 | Description                                                                                                  | Default |
+| --------------------------------------- | ------------------------------------------------------------------------------------------------------------ | ------- |
+| `MCP_SERVER_REQUEST_TIMEOUT`            | Timeout for requests to the MCP server (ms)                                                                  | 10000   |
+| `MCP_REQUEST_TIMEOUT_RESET_ON_PROGRESS` | Reset timeout on progress notifications                                                                      | true    |
+| `MCP_REQUEST_MAX_TOTAL_TIMEOUT`         | Maximum total timeout for requests sent to the MCP server (ms) (Use with progress notifications)             | 60000   |
+| `MCP_PROXY_FULL_ADDRESS`                | Set this if you are running the MCP Inspector Proxy on a non-default address. Example: http://10.1.1.22:5577 | ""      |
+
+These settings can be adjusted in real-time through the UI and will persist across sessions.
+
 ### From this repository
 
 If you're working on the inspector itself:

bin/cli.js

@@ -7,7 +7,7 @@ import { fileURLToPath } from "url";
 const __dirname = dirname(fileURLToPath(import.meta.url));
 
 function delay(ms) {
-  return new Promise((resolve) => setTimeout(resolve, ms));
+  return new Promise((resolve) => setTimeout(resolve, ms, true));
 }
 
 async function main() {
@@ -61,8 +61,8 @@ async function main() {
     "cli.js",
   );
 
-  const CLIENT_PORT = process.env.CLIENT_PORT ?? "5173";
-  const SERVER_PORT = process.env.SERVER_PORT ?? "3000";
+  const CLIENT_PORT = process.env.CLIENT_PORT ?? "6274";
+  const SERVER_PORT = process.env.SERVER_PORT ?? "6277";
 
   console.log("Starting MCP inspector...");
 
@@ -73,8 +73,9 @@ async function main() {
     cancelled = true;
     abort.abort();
   });
-
-  const server = spawnPromise(
+  let server, serverOk;
+  try {
+    server = spawnPromise(
       "node",
       [
         inspectorServerPath,
@@ -92,24 +93,21 @@ async function main() {
       },
     );
 
-  const client = spawnPromise("node", [inspectorClientPath], {
+    // Make sure server started before starting client
+    serverOk = await Promise.race([server, delay(2 * 1000)]);
+  } catch (error) {}
+
+  if (serverOk) {
+    try {
+      await spawnPromise("node", [inspectorClientPath], {
         env: { ...process.env, PORT: CLIENT_PORT },
         signal: abort.signal,
         echoOutput: true,
       });
-
-  // Make sure our server/client didn't immediately fail
-  await Promise.any([server, client, delay(2 * 1000)]);
-  const portParam = SERVER_PORT === "3000" ? "" : `?proxyPort=${SERVER_PORT}`;
-  console.log(
-    `\n🔍 MCP Inspector is up and running at http://localhost:${CLIENT_PORT}${portParam} 🚀`,
-  );
-
-  try {
-    await Promise.any([server, client]);
     } catch (e) {
       if (!cancelled || process.env.DEBUG) throw e;
     }
+  }
 
   return 0;
 }

client/bin/cli.js

@@ -15,5 +15,19 @@ const server = http.createServer((request, response) => {
   });
 });
 
-const port = process.env.PORT || 5173;
-server.listen(port, () => {});
+const port = process.env.PORT || 6274;
+server.on("listening", () => {
+  console.log(
+    `🔍 MCP Inspector is up and running at http://127.0.0.1:${port} 🚀`,
+  );
+});
+server.on("error", (err) => {
+  if (err.message.includes(`EADDRINUSE`)) {
+    console.error(
+      `❌  MCP Inspector PORT IS IN USE at http://127.0.0.1:${port} ❌ `,
+    );
+  } else {
+    throw err;
+  }
+});
+server.listen(port);

client/jest.config.cjs

@@ -3,16 +3,12 @@ module.exports = {
   testEnvironment: "jsdom",
   moduleNameMapper: {
     "^@/(.*)$": "<rootDir>/src/$1",
-    "^../components/DynamicJsonForm$":
-      "<rootDir>/src/utils/__mocks__/DynamicJsonForm.ts",
-    "^../../components/DynamicJsonForm$":
-      "<rootDir>/src/utils/__mocks__/DynamicJsonForm.ts",
+    "\\.css$": "<rootDir>/src/__mocks__/styleMock.js",
   },
   transform: {
     "^.+\\.tsx?$": [
       "ts-jest",
       {
-        useESM: true,
         jsx: "react-jsx",
         tsconfig: "tsconfig.jest.json",
       },

client/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@modelcontextprotocol/inspector-client",
-  "version": "0.7.0",
+  "version": "0.9.0",
   "description": "Client-side application for the Model Context Protocol inspector",
   "license": "MIT",
   "author": "Anthropic, PBC (https://anthropic.com)",
@@ -18,31 +18,31 @@
     "dev": "vite",
     "build": "tsc -b && vite build",
     "lint": "eslint .",
-    "preview": "vite preview",
+    "preview": "vite preview --port 6274",
     "test": "jest --config jest.config.cjs",
     "test:watch": "jest --config jest.config.cjs --watch"
   },
   "dependencies": {
-    "@modelcontextprotocol/sdk": "^1.6.1",
-    "@radix-ui/react-dialog": "^1.1.3",
+    "@modelcontextprotocol/sdk": "^1.9.0",
     "@radix-ui/react-checkbox": "^1.1.4",
+    "@radix-ui/react-dialog": "^1.1.3",
     "@radix-ui/react-icons": "^1.3.0",
     "@radix-ui/react-label": "^2.1.0",
     "@radix-ui/react-popover": "^1.1.3",
     "@radix-ui/react-select": "^2.1.2",
     "@radix-ui/react-slot": "^1.1.0",
     "@radix-ui/react-tabs": "^1.1.1",
-    "@types/prismjs": "^1.26.5",
+    "@radix-ui/react-toast": "^1.2.6",
+    "@radix-ui/react-tooltip": "^1.1.8",
     "class-variance-authority": "^0.7.0",
     "clsx": "^2.1.1",
     "cmdk": "^1.0.4",
     "lucide-react": "^0.447.0",
     "pkce-challenge": "^4.1.0",
-    "prismjs": "^1.29.0",
+    "prismjs": "^1.30.0",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
     "react-simple-code-editor": "^0.14.1",
-    "react-toastify": "^10.0.6",
     "serve-handler": "^6.1.6",
     "tailwind-merge": "^2.5.3",
     "tailwindcss-animate": "^1.0.7",
@@ -50,8 +50,11 @@
   },
   "devDependencies": {
     "@eslint/js": "^9.11.1",
+    "@testing-library/jest-dom": "^6.6.3",
+    "@testing-library/react": "^16.2.0",
     "@types/jest": "^29.5.14",
     "@types/node": "^22.7.5",
+    "@types/prismjs": "^1.26.5",
     "@types/react": "^18.3.10",
     "@types/react-dom": "^18.3.0",
     "@types/serve-handler": "^6.1.4",

client/src/App.tsx

@@ -20,7 +20,6 @@ import {
 import React, { Suspense, useEffect, useRef, useState } from "react";
 import { useConnection } from "./lib/hooks/useConnection";
 import { useDraggablePane } from "./lib/hooks/useDraggablePane";
-
 import { StdErrNotification } from "./lib/notificationTypes";
 
 import { Tabs, TabsList, TabsTrigger } from "@/components/ui/tabs";
@@ -33,7 +32,6 @@ import {
   MessageSquare,
 } from "lucide-react";
 
-import { toast } from "react-toastify";
 import { z } from "zod";
 import "./App.css";
 import ConsoleTab from "./components/ConsoleTab";
@@ -45,23 +43,17 @@ import RootsTab from "./components/RootsTab";
 import SamplingTab, { PendingRequest } from "./components/SamplingTab";
 import Sidebar from "./components/Sidebar";
 import ToolsTab from "./components/ToolsTab";
+import { DEFAULT_INSPECTOR_CONFIG } from "./lib/constants";
+import { InspectorConfig } from "./lib/configurationTypes";
+import { getMCPProxyAddress } from "./utils/configUtils";
+import { useToast } from "@/hooks/use-toast";
 
 const params = new URLSearchParams(window.location.search);
-const PROXY_PORT = params.get("proxyPort") ?? "3000";
-const PROXY_SERVER_URL = `http://${window.location.hostname}:${PROXY_PORT}`;
+const CONFIG_LOCAL_STORAGE_KEY = "inspectorConfig_v1";
 
 const App = () => {
+  const { toast } = useToast();
   // Handle OAuth callback route
-  if (window.location.pathname === "/oauth/callback") {
-    const OAuthCallback = React.lazy(
-      () => import("./components/OAuthCallback"),
-    );
-    return (
-      <Suspense fallback={<div>Loading...</div>}>
-        <OAuthCallback />
-      </Suspense>
-    );
-  }
   const [resources, setResources] = useState<Resource[]>([]);
   const [resourceTemplates, setResourceTemplates] = useState<
     ResourceTemplate[]
@@ -99,6 +91,28 @@ const App = () => {
   >([]);
   const [roots, setRoots] = useState<Root[]>([]);
   const [env, setEnv] = useState<Record<string, string>>({});
+
+  const [config, setConfig] = useState<InspectorConfig>(() => {
+    const savedConfig = localStorage.getItem(CONFIG_LOCAL_STORAGE_KEY);
+    if (savedConfig) {
+      // merge default config with saved config
+      const mergedConfig = {
+        ...DEFAULT_INSPECTOR_CONFIG,
+        ...JSON.parse(savedConfig),
+      } as InspectorConfig;
+
+      // update description of keys to match the new description (in case of any updates to the default config description)
+      Object.entries(mergedConfig).forEach(([key, value]) => {
+        mergedConfig[key as keyof InspectorConfig] = {
+          ...value,
+          label: DEFAULT_INSPECTOR_CONFIG[key as keyof InspectorConfig].label,
+        };
+      });
+
+      return mergedConfig;
+    }
+    return DEFAULT_INSPECTOR_CONFIG;
+  });
   const [bearerToken, setBearerToken] = useState<string>(() => {
     return localStorage.getItem("lastBearerToken") || "";
   });
@@ -114,22 +128,6 @@ const App = () => {
   const nextRequestId = useRef(0);
   const rootsRef = useRef<Root[]>([]);
 
-  const handleApproveSampling = (id: number, result: CreateMessageResult) => {
-    setPendingSampleRequests((prev) => {
-      const request = prev.find((r) => r.id === id);
-      request?.resolve(result);
-      return prev.filter((r) => r.id !== id);
-    });
-  };
-
-  const handleRejectSampling = (id: number) => {
-    setPendingSampleRequests((prev) => {
-      const request = prev.find((r) => r.id === id);
-      request?.reject(new Error("Sampling request rejected"));
-      return prev.filter((r) => r.id !== id);
-    });
-  };
-
   const [selectedResource, setSelectedResource] = useState<Resource | null>(
     null,
   );
@@ -158,11 +156,12 @@ const App = () => {
     serverCapabilities,
     mcpClient,
     requestHistory,
-    makeRequest: makeConnectionRequest,
+    makeRequest,
     sendNotification,
     handleCompletion,
     completionsSupported,
     connect: connectMcpServer,
+    disconnect: disconnectMcpServer,
   } = useConnection({
     transportType,
     command,
@@ -170,7 +169,7 @@ const App = () => {
     sseUrl,
     env,
     bearerToken,
-    proxyServerUrl: PROXY_SERVER_URL,
+    config,
     onNotification: (notification) => {
       setNotifications((prev) => [...prev, notification as ServerNotification]);
     },
@@ -209,8 +208,17 @@ const App = () => {
     localStorage.setItem("lastBearerToken", bearerToken);
   }, [bearerToken]);
 
+  useEffect(() => {
+    localStorage.setItem(CONFIG_LOCAL_STORAGE_KEY, JSON.stringify(config));
+  }, [config]);
+
+  const hasProcessedRef = useRef(false);
   // Auto-connect if serverUrl is provided in URL params (e.g. after OAuth callback)
   useEffect(() => {
+    if (hasProcessedRef.current) {
+      // Only try to connect once
+      return;
+    }
     const serverUrl = params.get("serverUrl");
     if (serverUrl) {
       setSseUrl(serverUrl);
@@ -220,14 +228,18 @@ const App = () => {
       newUrl.searchParams.delete("serverUrl");
       window.history.replaceState({}, "", newUrl.toString());
       // Show success toast for OAuth
-      toast.success("Successfully authenticated with OAuth");
+      toast({
+        title: "Success",
+        description: "Successfully authenticated with OAuth",
+      });
+      hasProcessedRef.current = true;
       // Connect to the server
       connectMcpServer();
     }
-  }, []);
+  }, [connectMcpServer, toast]);
 
   useEffect(() => {
-    fetch(`${PROXY_SERVER_URL}/config`)
+    fetch(`${getMCPProxyAddress(config)}/config`)
       .then((response) => response.json())
       .then((data) => {
         setEnv(data.defaultEnvironment);
@@ -241,6 +253,7 @@ const App = () => {
       .catch((error) =>
         console.error("Error fetching default environment:", error),
       );
+    // eslint-disable-next-line react-hooks/exhaustive-deps
   }, []);
 
   useEffect(() => {
@@ -253,17 +266,33 @@ const App = () => {
     }
   }, []);
 
+  const handleApproveSampling = (id: number, result: CreateMessageResult) => {
+    setPendingSampleRequests((prev) => {
+      const request = prev.find((r) => r.id === id);
+      request?.resolve(result);
+      return prev.filter((r) => r.id !== id);
+    });
+  };
+
+  const handleRejectSampling = (id: number) => {
+    setPendingSampleRequests((prev) => {
+      const request = prev.find((r) => r.id === id);
+      request?.reject(new Error("Sampling request rejected"));
+      return prev.filter((r) => r.id !== id);
+    });
+  };
+
   const clearError = (tabKey: keyof typeof errors) => {
     setErrors((prev) => ({ ...prev, [tabKey]: null }));
   };
 
-  const makeRequest = async <T extends z.ZodType>(
+  const sendMCPRequest = async <T extends z.ZodType>(
     request: ClientRequest,
     schema: T,
     tabKey?: keyof typeof errors,
   ) => {
     try {
-      const response = await makeConnectionRequest(request, schema);
+      const response = await makeRequest(request, schema);
       if (tabKey !== undefined) {
         clearError(tabKey);
       }
@@ -281,7 +310,7 @@ const App = () => {
   };
 
   const listResources = async () => {
-    const response = await makeRequest(
+    const response = await sendMCPRequest(
       {
         method: "resources/list" as const,
         params: nextResourceCursor ? { cursor: nextResourceCursor } : {},
@@ -294,7 +323,7 @@ const App = () => {
   };
 
   const listResourceTemplates = async () => {
-    const response = await makeRequest(
+    const response = await sendMCPRequest(
       {
         method: "resources/templates/list" as const,
         params: nextResourceTemplateCursor
@@ -311,7 +340,7 @@ const App = () => {
   };
 
   const readResource = async (uri: string) => {
-    const response = await makeRequest(
+    const response = await sendMCPRequest(
       {
         method: "resources/read" as const,
         params: { uri },
@@ -324,7 +353,7 @@ const App = () => {
 
   const subscribeToResource = async (uri: string) => {
     if (!resourceSubscriptions.has(uri)) {
-      await makeRequest(
+      await sendMCPRequest(
         {
           method: "resources/subscribe" as const,
           params: { uri },
@@ -340,7 +369,7 @@ const App = () => {
 
   const unsubscribeFromResource = async (uri: string) => {
     if (resourceSubscriptions.has(uri)) {
-      await makeRequest(
+      await sendMCPRequest(
         {
           method: "resources/unsubscribe" as const,
           params: { uri },
@@ -355,7 +384,7 @@ const App = () => {
   };
 
   const listPrompts = async () => {
-    const response = await makeRequest(
+    const response = await sendMCPRequest(
       {
         method: "prompts/list" as const,
         params: nextPromptCursor ? { cursor: nextPromptCursor } : {},
@@ -368,7 +397,7 @@ const App = () => {
   };
 
   const getPrompt = async (name: string, args: Record<string, string> = {}) => {
-    const response = await makeRequest(
+    const response = await sendMCPRequest(
       {
         method: "prompts/get" as const,
         params: { name, arguments: args },
@@ -380,7 +409,7 @@ const App = () => {
   };
 
   const listTools = async () => {
-    const response = await makeRequest(
+    const response = await sendMCPRequest(
       {
         method: "tools/list" as const,
         params: nextToolCursor ? { cursor: nextToolCursor } : {},
@@ -393,7 +422,8 @@ const App = () => {
   };
 
   const callTool = async (name: string, params: Record<string, unknown>) => {
-    const response = await makeRequest(
+    try {
+      const response = await sendMCPRequest(
         {
           method: "tools/call" as const,
           params: {
@@ -408,6 +438,18 @@ const App = () => {
         "tools",
       );
       setToolResult(response);
+    } catch (e) {
+      const toolResult: CompatibilityCallToolResult = {
+        content: [
+          {
+            type: "text",
+            text: (e as Error).message ?? String(e),
+          },
+        ],
+        isError: true,
+      };
+      setToolResult(toolResult);
+    }
   };
 
   const handleRootsChange = async () => {
@@ -415,7 +457,7 @@ const App = () => {
   };
 
   const sendLogLevelRequest = async (level: LoggingLevel) => {
-    await makeRequest(
+    await sendMCPRequest(
       {
         method: "logging/setLevel" as const,
         params: { level },
@@ -425,6 +467,17 @@ const App = () => {
     setLogLevel(level);
   };
 
+  if (window.location.pathname === "/oauth/callback") {
+    const OAuthCallback = React.lazy(
+      () => import("./components/OAuthCallback"),
+    );
+    return (
+      <Suspense fallback={<div>Loading...</div>}>
+        <OAuthCallback />
+      </Suspense>
+    );
+  }
+
   return (
     <div className="flex h-screen bg-background">
       <Sidebar
@@ -439,9 +492,12 @@ const App = () => {
         setSseUrl={setSseUrl}
         env={env}
         setEnv={setEnv}
+        config={config}
+        setConfig={setConfig}
         bearerToken={bearerToken}
         setBearerToken={setBearerToken}
         onConnect={connectMcpServer}
+        onDisconnect={disconnectMcpServer}
         stdErrNotifications={stdErrNotifications}
         logLevel={logLevel}
         sendLogLevelRequest={sendLogLevelRequest}
@@ -601,9 +657,10 @@ const App = () => {
                         setTools([]);
                         setNextToolCursor(undefined);
                       }}
-                      callTool={(name, params) => {
+                      callTool={async (name, params) => {
                         clearError("tools");
-                        callTool(name, params);
+                        setToolResult(null);
+                        await callTool(name, params);
                       }}
                       selectedTool={selectedTool}
                       setSelectedTool={(tool) => {
@@ -618,7 +675,7 @@ const App = () => {
                     <ConsoleTab />
                     <PingTab
                       onPingClick={() => {
-                        void makeRequest(
+                        void sendMCPRequest(
                           {
                             method: "ping" as const,
                           },

client/src/__mocks__/styleMock.js

@@ -0,0 +1 @@
+module.exports = {};

client/src/components/DynamicJsonForm.tsx

@@ -3,33 +3,9 @@ import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Label } from "@/components/ui/label";
 import JsonEditor from "./JsonEditor";
-import { updateValueAtPath, JsonObject } from "@/utils/jsonPathUtils";
+import { updateValueAtPath } from "@/utils/jsonUtils";
 import { generateDefaultValue, formatFieldLabel } from "@/utils/schemaUtils";
-
-export type JsonValue =
-  | string
-  | number
-  | boolean
-  | null
-  | undefined
-  | JsonValue[]
-  | { [key: string]: JsonValue };
-
-export type JsonSchemaType = {
-  type:
-    | "string"
-    | "number"
-    | "integer"
-    | "boolean"
-    | "array"
-    | "object"
-    | "null";
-  description?: string;
-  required?: boolean;
-  default?: JsonValue;
-  properties?: Record<string, JsonSchemaType>;
-  items?: JsonSchemaType;
-};
+import type { JsonValue, JsonSchemaType, JsonObject } from "@/utils/jsonUtils";
 
 interface DynamicJsonFormProps {
   schema: JsonSchemaType;
@@ -108,6 +84,21 @@ const DynamicJsonForm = ({
     }
   };
 
+  const formatJson = () => {
+    try {
+      const jsonStr = rawJsonValue.trim();
+      if (!jsonStr) {
+        return;
+      }
+      const formatted = JSON.stringify(JSON.parse(jsonStr), null, 2);
+      setRawJsonValue(formatted);
+      debouncedUpdateParent(formatted);
+      setJsonError(undefined);
+    } catch (err) {
+      setJsonError(err instanceof Error ? err.message : "Invalid JSON");
+    }
+  };
+
   const renderFormFields = (
     propSchema: JsonSchemaType,
     currentValue: JsonValue,
@@ -353,7 +344,12 @@ const DynamicJsonForm = ({
 
   return (
     <div className="space-y-4">
-      <div className="flex justify-end">
+      <div className="flex justify-end space-x-2">
+        {isJsonMode && (
+          <Button variant="outline" size="sm" onClick={formatJson}>
+            Format JSON
+          </Button>
+        )}
         <Button variant="outline" size="sm" onClick={handleSwitchToFormMode}>
           {isJsonMode ? "Switch to Form" : "Switch to JSON"}
         </Button>

client/src/components/History.tsx

@@ -1,6 +1,6 @@
 import { ServerNotification } from "@modelcontextprotocol/sdk/types.js";
-import { Copy } from "lucide-react";
 import { useState } from "react";
+import JsonView from "./JsonView";
 
 const HistoryAndNotifications = ({
   requestHistory,
@@ -24,10 +24,6 @@ const HistoryAndNotifications = ({
     setExpandedNotifications((prev) => ({ ...prev, [index]: !prev[index] }));
   };
 
-  const copyToClipboard = (text: string) => {
-    navigator.clipboard.writeText(text);
-  };
-
   return (
     <div className="bg-card overflow-hidden flex h-full">
       <div className="flex-1 overflow-y-auto p-4 border-r">
@@ -67,16 +63,12 @@ const HistoryAndNotifications = ({
                           <span className="font-semibold text-blue-600">
                             Request:
                           </span>
-                          <button
-                            onClick={() => copyToClipboard(request.request)}
-                            className="text-blue-500 hover:text-blue-700"
-                          >
-                            <Copy size={16} />
-                          </button>
                         </div>
-                        <pre className="whitespace-pre-wrap break-words bg-background p-2 rounded">
-                          {JSON.stringify(JSON.parse(request.request), null, 2)}
-                        </pre>
+
+                        <JsonView
+                          data={request.request}
+                          className="bg-background"
+                        />
                       </div>
                       {request.response && (
                         <div className="mt-2">
@@ -84,20 +76,11 @@ const HistoryAndNotifications = ({
                             <span className="font-semibold text-green-600">
                               Response:
                             </span>
-                            <button
-                              onClick={() => copyToClipboard(request.response!)}
-                              className="text-blue-500 hover:text-blue-700"
-                            >
-                              <Copy size={16} />
-                            </button>
                           </div>
-                          <pre className="whitespace-pre-wrap break-words bg-background p-2 rounded">
-                            {JSON.stringify(
-                              JSON.parse(request.response),
-                              null,
-                              2,
-                            )}
-                          </pre>
+                          <JsonView
+                            data={request.response}
+                            className="bg-background"
+                          />
                         </div>
                       )}
                     </>
@@ -137,18 +120,11 @@ const HistoryAndNotifications = ({
                         <span className="font-semibold text-purple-600">
                           Details:
                         </span>
-                        <button
-                          onClick={() =>
-                            copyToClipboard(JSON.stringify(notification))
-                          }
-                          className="text-blue-500 hover:text-blue-700"
-                        >
-                          <Copy size={16} />
-                        </button>
                       </div>
-                      <pre className="whitespace-pre-wrap break-words bg-background p-2 rounded">
-                        {JSON.stringify(notification, null, 2)}
-                      </pre>
+                      <JsonView
+                        data={JSON.stringify(notification, null, 2)}
+                        className="bg-background"
+                      />
                     </div>
                   )}
                 </li>

client/src/components/JsonEditor.tsx

@@ -3,7 +3,6 @@ import Editor from "react-simple-code-editor";
 import Prism from "prismjs";
 import "prismjs/components/prism-json";
 import "prismjs/themes/prism.css";
-import { Button } from "@/components/ui/button";
 
 interface JsonEditorProps {
   value: string;
@@ -16,49 +15,25 @@ const JsonEditor = ({
   onChange,
   error: externalError,
 }: JsonEditorProps) => {
-  const [editorContent, setEditorContent] = useState(value);
+  const [editorContent, setEditorContent] = useState(value || "");
   const [internalError, setInternalError] = useState<string | undefined>(
     undefined,
   );
 
   useEffect(() => {
-    setEditorContent(value);
+    setEditorContent(value || "");
   }, [value]);
 
-  const formatJson = (json: string): string => {
-    try {
-      return JSON.stringify(JSON.parse(json), null, 2);
-    } catch {
-      return json;
-    }
-  };
-
   const handleEditorChange = (newContent: string) => {
     setEditorContent(newContent);
     setInternalError(undefined);
     onChange(newContent);
   };
 
-  const handleFormatJson = () => {
-    try {
-      const formatted = formatJson(editorContent);
-      setEditorContent(formatted);
-      onChange(formatted);
-      setInternalError(undefined);
-    } catch (err) {
-      setInternalError(err instanceof Error ? err.message : "Invalid JSON");
-    }
-  };
-
   const displayError = internalError || externalError;
 
   return (
-    <div className="relative space-y-2">
-      <div className="flex justify-end">
-        <Button variant="outline" size="sm" onClick={handleFormatJson}>
-          Format JSON
-        </Button>
-      </div>
+    <div className="relative">
       <div
         className={`border rounded-md ${
           displayError

client/src/components/JsonView.tsx

@@ -0,0 +1,286 @@
+import { useState, memo, useMemo, useCallback, useEffect } from "react";
+import type { JsonValue } from "@/utils/jsonUtils";
+import clsx from "clsx";
+import { Copy, CheckCheck } from "lucide-react";
+import { Button } from "@/components/ui/button";
+import { useToast } from "@/hooks/use-toast";
+import { getDataType, tryParseJson } from "@/utils/jsonUtils";
+
+interface JsonViewProps {
+  data: unknown;
+  name?: string;
+  initialExpandDepth?: number;
+  className?: string;
+  withCopyButton?: boolean;
+  isError?: boolean;
+}
+
+const JsonView = memo(
+  ({
+    data,
+    name,
+    initialExpandDepth = 3,
+    className,
+    withCopyButton = true,
+    isError = false,
+  }: JsonViewProps) => {
+    const { toast } = useToast();
+    const [copied, setCopied] = useState(false);
+
+    useEffect(() => {
+      let timeoutId: NodeJS.Timeout;
+      if (copied) {
+        timeoutId = setTimeout(() => {
+          setCopied(false);
+        }, 500);
+      }
+      return () => {
+        if (timeoutId) {
+          clearTimeout(timeoutId);
+        }
+      };
+    }, [copied]);
+
+    const normalizedData = useMemo(() => {
+      return typeof data === "string"
+        ? tryParseJson(data).success
+          ? tryParseJson(data).data
+          : data
+        : data;
+    }, [data]);
+
+    const handleCopy = useCallback(() => {
+      try {
+        navigator.clipboard.writeText(
+          typeof normalizedData === "string"
+            ? normalizedData
+            : JSON.stringify(normalizedData, null, 2),
+        );
+        setCopied(true);
+      } catch (error) {
+        toast({
+          title: "Error",
+          description: `There was an error coping result into the clipboard: ${error instanceof Error ? error.message : String(error)}`,
+          variant: "destructive",
+        });
+      }
+    }, [toast, normalizedData]);
+
+    return (
+      <div className={clsx("p-4 border rounded relative", className)}>
+        {withCopyButton && (
+          <Button
+            size="icon"
+            variant="ghost"
+            className="absolute top-2 right-2"
+            onClick={handleCopy}
+          >
+            {copied ? (
+              <CheckCheck className="size-4 dark:text-green-700 text-green-600" />
+            ) : (
+              <Copy className="size-4 text-foreground" />
+            )}
+          </Button>
+        )}
+        <div className="font-mono text-sm transition-all duration-300">
+          <JsonNode
+            data={normalizedData as JsonValue}
+            name={name}
+            depth={0}
+            initialExpandDepth={initialExpandDepth}
+            isError={isError}
+          />
+        </div>
+      </div>
+    );
+  },
+);
+
+JsonView.displayName = "JsonView";
+
+interface JsonNodeProps {
+  data: JsonValue;
+  name?: string;
+  depth: number;
+  initialExpandDepth: number;
+  isError?: boolean;
+}
+
+const JsonNode = memo(
+  ({
+    data,
+    name,
+    depth = 0,
+    initialExpandDepth,
+    isError = false,
+  }: JsonNodeProps) => {
+    const [isExpanded, setIsExpanded] = useState(depth < initialExpandDepth);
+    const [typeStyleMap] = useState<Record<string, string>>({
+      number: "text-blue-600",
+      boolean: "text-amber-600",
+      null: "text-purple-600",
+      undefined: "text-gray-600",
+      string: "text-green-600 group-hover:text-green-500",
+      error: "text-red-600 group-hover:text-red-500",
+      default: "text-gray-700",
+    });
+    const dataType = getDataType(data);
+
+    const renderCollapsible = (isArray: boolean) => {
+      const items = isArray
+        ? (data as JsonValue[])
+        : Object.entries(data as Record<string, JsonValue>);
+      const itemCount = items.length;
+      const isEmpty = itemCount === 0;
+
+      const symbolMap = {
+        open: isArray ? "[" : "{",
+        close: isArray ? "]" : "}",
+        collapsed: isArray ? "[ ... ]" : "{ ... }",
+        empty: isArray ? "[]" : "{}",
+      };
+
+      if (isEmpty) {
+        return (
+          <div className="flex items-center">
+            {name && (
+              <span className="mr-1 text-gray-600 dark:text-gray-400">
+                {name}:
+              </span>
+            )}
+            <span className="text-gray-500">{symbolMap.empty}</span>
+          </div>
+        );
+      }
+
+      return (
+        <div className="flex flex-col">
+          <div
+            className="flex items-center mr-1 rounded cursor-pointer group hover:bg-gray-800/10 dark:hover:bg-gray-800/20"
+            onClick={() => setIsExpanded(!isExpanded)}
+          >
+            {name && (
+              <span className="mr-1 text-gray-600 dark:text-gray-400 dark:group-hover:text-gray-100 group-hover:text-gray-400">
+                {name}:
+              </span>
+            )}
+            {isExpanded ? (
+              <span className="text-gray-600 dark:text-gray-400 dark:group-hover:text-gray-100 group-hover:text-gray-400">
+                {symbolMap.open}
+              </span>
+            ) : (
+              <>
+                <span className="text-gray-600 dark:group-hover:text-gray-100 group-hover:text-gray-400">
+                  {symbolMap.collapsed}
+                </span>
+                <span className="ml-1 text-gray-700 dark:group-hover:text-gray-100 group-hover:text-gray-400">
+                  {itemCount} {itemCount === 1 ? "item" : "items"}
+                </span>
+              </>
+            )}
+          </div>
+          {isExpanded && (
+            <>
+              <div className="pl-2 ml-4 border-l border-gray-200 dark:border-gray-800">
+                {isArray
+                  ? (items as JsonValue[]).map((item, index) => (
+                      <div key={index} className="my-1">
+                        <JsonNode
+                          data={item}
+                          name={`${index}`}
+                          depth={depth + 1}
+                          initialExpandDepth={initialExpandDepth}
+                        />
+                      </div>
+                    ))
+                  : (items as [string, JsonValue][]).map(([key, value]) => (
+                      <div key={key} className="my-1">
+                        <JsonNode
+                          data={value}
+                          name={key}
+                          depth={depth + 1}
+                          initialExpandDepth={initialExpandDepth}
+                        />
+                      </div>
+                    ))}
+              </div>
+              <div className="text-gray-600 dark:text-gray-400">
+                {symbolMap.close}
+              </div>
+            </>
+          )}
+        </div>
+      );
+    };
+
+    const renderString = (value: string) => {
+      const maxLength = 100;
+      const isTooLong = value.length > maxLength;
+
+      if (!isTooLong) {
+        return (
+          <div className="flex mr-1 rounded hover:bg-gray-800/20">
+            {name && (
+              <span className="mr-1 text-gray-600 dark:text-gray-400">
+                {name}:
+              </span>
+            )}
+            <pre
+              className={clsx(
+                typeStyleMap.string,
+                "break-all whitespace-pre-wrap",
+              )}
+            >
+              "{value}"
+            </pre>
+          </div>
+        );
+      }
+
+      return (
+        <div className="flex mr-1 rounded group hover:bg-gray-800/20">
+          {name && (
+            <span className="mr-1 text-gray-600 dark:text-gray-400 dark:group-hover:text-gray-100 group-hover:text-gray-400">
+              {name}:
+            </span>
+          )}
+          <pre
+            className={clsx(
+              isError ? typeStyleMap.error : typeStyleMap.string,
+              "cursor-pointer break-all whitespace-pre-wrap",
+            )}
+            onClick={() => setIsExpanded(!isExpanded)}
+            title={isExpanded ? "Click to collapse" : "Click to expand"}
+          >
+            {isExpanded ? `"${value}"` : `"${value.slice(0, maxLength)}..."`}
+          </pre>
+        </div>
+      );
+    };
+
+    switch (dataType) {
+      case "object":
+      case "array":
+        return renderCollapsible(dataType === "array");
+      case "string":
+        return renderString(data as string);
+      default:
+        return (
+          <div className="flex items-center mr-1 rounded hover:bg-gray-800/20">
+            {name && (
+              <span className="mr-1 text-gray-600 dark:text-gray-400">
+                {name}:
+              </span>
+            )}
+            <span className={typeStyleMap[dataType] || typeStyleMap.default}>
+              {data === null ? "null" : String(data)}
+            </span>
+          </div>
+        );
+    }
+  },
+);
+
+JsonNode.displayName = "JsonNode";
+
+export default JsonView;

client/src/components/ListPane.tsx

@@ -22,7 +22,7 @@ const ListPane = <T extends object>({
   isButtonDisabled,
 }: ListPaneProps<T>) => (
   <div className="bg-card rounded-lg shadow">
-    <div className="p-4 border-b border-gray-200 dark:border-gray-700">
+    <div className="p-4 border-b border-gray-200 dark:border-gray-800">
       <h3 className="font-semibold dark:text-white">{title}</h3>
     </div>
     <div className="p-4">

client/src/components/PingTab.tsx

@@ -3,7 +3,8 @@ import { Button } from "@/components/ui/button";
 
 const PingTab = ({ onPingClick }: { onPingClick: () => void }) => {
   return (
-    <TabsContent value="ping" className="grid grid-cols-2 gap-4">
+    <TabsContent value="ping">
+      <div className="grid grid-cols-2 gap-4">
         <div className="col-span-2 flex justify-center items-center">
           <Button
             onClick={onPingClick}
@@ -12,6 +13,7 @@ const PingTab = ({ onPingClick }: { onPingClick: () => void }) => {
             Ping Server
           </Button>
         </div>
+      </div>
     </TabsContent>
   );
 };

client/src/components/PromptsTab.tsx

@@ -3,7 +3,7 @@ import { Button } from "@/components/ui/button";
 import { Combobox } from "@/components/ui/combobox";
 import { Label } from "@/components/ui/label";
 import { TabsContent } from "@/components/ui/tabs";
-import { Textarea } from "@/components/ui/textarea";
+
 import {
   ListPromptsResult,
   PromptReference,
@@ -13,6 +13,7 @@ import { AlertCircle } from "lucide-react";
 import { useEffect, useState } from "react";
 import ListPane from "./ListPane";
 import { useCompletionState } from "@/lib/hooks/useCompletionState";
+import JsonView from "./JsonView";
 
 export type Prompt = {
   name: string;
@@ -83,7 +84,8 @@ const PromptsTab = ({
   };
 
   return (
-    <TabsContent value="prompts" className="grid grid-cols-2 gap-4">
+    <TabsContent value="prompts">
+      <div className="grid grid-cols-2 gap-4">
         <ListPane
           items={prompts}
           listItems={listPrompts}
@@ -95,7 +97,9 @@ const PromptsTab = ({
           renderItem={(prompt) => (
             <>
               <span className="flex-1">{prompt.name}</span>
-            <span className="text-sm text-gray-500">{prompt.description}</span>
+              <span className="text-sm text-gray-500">
+                {prompt.description}
+              </span>
             </>
           )}
           title="Prompts"
@@ -104,7 +108,7 @@ const PromptsTab = ({
         />
 
         <div className="bg-card rounded-lg shadow">
-        <div className="p-4 border-b border-gray-200">
+          <div className="p-4 border-b border-gray-200 dark:border-gray-800">
             <h3 className="font-semibold">
               {selectedPrompt ? selectedPrompt.name : "Select a prompt"}
             </h3>
@@ -151,11 +155,7 @@ const PromptsTab = ({
                   Get Prompt
                 </Button>
                 {promptContent && (
-                <Textarea
-                  value={promptContent}
-                  readOnly
-                  className="h-64 font-mono"
-                />
+                  <JsonView data={promptContent} withCopyButton={false} />
                 )}
               </div>
             ) : (
@@ -167,6 +167,7 @@ const PromptsTab = ({
             )}
           </div>
         </div>
+      </div>
     </TabsContent>
   );
 };

client/src/components/ResourcesTab.tsx

@@ -15,6 +15,7 @@ import { AlertCircle, ChevronRight, FileText, RefreshCw } from "lucide-react";
 import ListPane from "./ListPane";
 import { useEffect, useState } from "react";
 import { useCompletionState } from "@/lib/hooks/useCompletionState";
+import JsonView from "./JsonView";
 
 const ResourcesTab = ({
   resources,
@@ -110,7 +111,8 @@ const ResourcesTab = ({
   };
 
   return (
-    <TabsContent value="resources" className="grid grid-cols-3 gap-4">
+    <TabsContent value="resources">
+      <div className="grid grid-cols-3 gap-4">
         <ListPane
           items={resources}
           listItems={listResources}
@@ -160,7 +162,7 @@ const ResourcesTab = ({
         />
 
         <div className="bg-card rounded-lg shadow">
-        <div className="p-4 border-b border-gray-200 flex justify-between items-center">
+          <div className="p-4 border-b border-gray-200 dark:border-gray-800 flex justify-between items-center">
             <h3
               className="font-semibold truncate"
               title={selectedResource?.name || selectedTemplate?.name}
@@ -214,9 +216,10 @@ const ResourcesTab = ({
                 <AlertDescription>{error}</AlertDescription>
               </Alert>
             ) : selectedResource ? (
-            <pre className="bg-gray-50 dark:bg-gray-800 p-4 rounded text-sm overflow-auto max-h-96 whitespace-pre-wrap break-words text-gray-900 dark:text-gray-100">
-              {resourceContent}
-            </pre>
+              <JsonView
+                data={resourceContent}
+                className="bg-gray-50 dark:bg-gray-800 p-4 rounded text-sm overflow-auto max-h-96 text-gray-900 dark:text-gray-100"
+              />
             ) : selectedTemplate ? (
               <div className="space-y-4">
                 <p className="text-sm text-gray-600">
@@ -254,12 +257,14 @@ const ResourcesTab = ({
             ) : (
               <Alert>
                 <AlertDescription>
-                Select a resource or template from the list to view its contents
+                  Select a resource or template from the list to view its
+                  contents
                 </AlertDescription>
               </Alert>
             )}
           </div>
         </div>
+      </div>
     </TabsContent>
   );
 };

client/src/components/RootsTab.tsx

@@ -35,7 +35,8 @@ const RootsTab = ({
   };
 
   return (
-    <TabsContent value="roots" className="space-y-4">
+    <TabsContent value="roots">
+      <div className="space-y-4">
         <Alert>
           <AlertDescription>
             Configure the root directories that the server can access
@@ -70,6 +71,7 @@ const RootsTab = ({
             Save Changes
           </Button>
         </div>
+      </div>
     </TabsContent>
   );
 };

client/src/components/SamplingTab.tsx

@@ -5,6 +5,7 @@ import {
   CreateMessageRequest,
   CreateMessageResult,
 } from "@modelcontextprotocol/sdk/types.js";
+import JsonView from "./JsonView";
 
 export type PendingRequest = {
   id: number;
@@ -32,7 +33,8 @@ const SamplingTab = ({ pendingRequests, onApprove, onReject }: Props) => {
   };
 
   return (
-    <TabsContent value="sampling" className="h-96">
+    <TabsContent value="sampling">
+      <div className="h-96">
         <Alert>
           <AlertDescription>
             When the server requests LLM sampling, requests will appear here for
@@ -43,11 +45,15 @@ const SamplingTab = ({ pendingRequests, onApprove, onReject }: Props) => {
           <h3 className="text-lg font-semibold">Recent Requests</h3>
           {pendingRequests.map((request) => (
             <div key={request.id} className="p-4 border rounded-lg space-y-4">
-            <pre className="bg-gray-50 dark:bg-gray-800 dark:text-gray-100 p-2 rounded">
-              {JSON.stringify(request.request, null, 2)}
-            </pre>
+              <JsonView
+                className="bg-gray-50 dark:bg-gray-800 dark:text-gray-100 rounded"
+                data={JSON.stringify(request.request)}
+              />
+
               <div className="flex space-x-2">
-              <Button onClick={() => handleApprove(request.id)}>Approve</Button>
+                <Button onClick={() => handleApprove(request.id)}>
+                  Approve
+                </Button>
                 <Button variant="outline" onClick={() => onReject(request.id)}>
                   Reject
                 </Button>
@@ -58,6 +64,7 @@ const SamplingTab = ({ pendingRequests, onApprove, onReject }: Props) => {
             <p className="text-gray-500">No pending requests</p>
           )}
         </div>
+      </div>
     </TabsContent>
   );
 };

client/src/components/Sidebar.tsx

@@ -8,6 +8,10 @@ import {
   Github,
   Eye,
   EyeOff,
+  RotateCcw,
+  Settings,
+  HelpCircle,
+  RefreshCwOff,
 } from "lucide-react";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
@@ -23,12 +27,18 @@ import {
   LoggingLevel,
   LoggingLevelSchema,
 } from "@modelcontextprotocol/sdk/types.js";
-
+import { InspectorConfig } from "@/lib/configurationTypes";
+import { ConnectionStatus } from "@/lib/constants";
 import useTheme from "../lib/useTheme";
 import { version } from "../../../package.json";
+import {
+  Tooltip,
+  TooltipTrigger,
+  TooltipContent,
+} from "@/components/ui/tooltip";
 
 interface SidebarProps {
-  connectionStatus: "disconnected" | "connected" | "error";
+  connectionStatus: ConnectionStatus;
   transportType: "stdio" | "sse";
   setTransportType: (type: "stdio" | "sse") => void;
   command: string;
@@ -42,10 +52,13 @@ interface SidebarProps {
   bearerToken: string;
   setBearerToken: (token: string) => void;
   onConnect: () => void;
+  onDisconnect: () => void;
   stdErrNotifications: StdErrNotification[];
   logLevel: LoggingLevel;
   sendLogLevelRequest: (level: LoggingLevel) => void;
   loggingSupported: boolean;
+  config: InspectorConfig;
+  setConfig: (config: InspectorConfig) => void;
 }
 
 const Sidebar = ({
@@ -63,19 +76,23 @@ const Sidebar = ({
   bearerToken,
   setBearerToken,
   onConnect,
+  onDisconnect,
   stdErrNotifications,
   logLevel,
   sendLogLevelRequest,
   loggingSupported,
+  config,
+  setConfig,
 }: SidebarProps) => {
   const [theme, setTheme] = useTheme();
   const [showEnvVars, setShowEnvVars] = useState(false);
   const [showBearerToken, setShowBearerToken] = useState(false);
+  const [showConfig, setShowConfig] = useState(false);
   const [shownEnvVars, setShownEnvVars] = useState<Set<string>>(new Set());
 
   return (
     <div className="w-80 bg-card border-r border-border flex flex-col h-full">
-      <div className="flex items-center justify-between p-4 border-b border-gray-200">
+      <div className="flex items-center justify-between p-4 border-b border-gray-200 dark:border-gray-800">
         <div className="flex items-center">
           <h1 className="ml-2 text-lg font-semibold">
             MCP Inspector v{version}
@@ -86,14 +103,19 @@ const Sidebar = ({
       <div className="p-4 flex-1 overflow-auto">
         <div className="space-y-4">
           <div className="space-y-2">
-            <label className="text-sm font-medium">Transport Type</label>
+            <label
+              className="text-sm font-medium"
+              htmlFor="transport-type-select"
+            >
+              Transport Type
+            </label>
             <Select
               value={transportType}
               onValueChange={(value: "stdio" | "sse") =>
                 setTransportType(value)
               }
             >
-              <SelectTrigger>
+              <SelectTrigger id="transport-type-select">
                 <SelectValue placeholder="Select transport type" />
               </SelectTrigger>
               <SelectContent>
@@ -106,8 +128,11 @@ const Sidebar = ({
           {transportType === "stdio" ? (
             <>
               <div className="space-y-2">
-                <label className="text-sm font-medium">Command</label>
+                <label className="text-sm font-medium" htmlFor="command-input">
+                  Command
+                </label>
                 <Input
+                  id="command-input"
                   placeholder="Command"
                   value={command}
                   onChange={(e) => setCommand(e.target.value)}
@@ -115,8 +140,14 @@ const Sidebar = ({
                 />
               </div>
               <div className="space-y-2">
-                <label className="text-sm font-medium">Arguments</label>
+                <label
+                  className="text-sm font-medium"
+                  htmlFor="arguments-input"
+                >
+                  Arguments
+                </label>
                 <Input
+                  id="arguments-input"
                   placeholder="Arguments (space-separated)"
                   value={args}
                   onChange={(e) => setArgs(e.target.value)}
@@ -127,8 +158,11 @@ const Sidebar = ({
           ) : (
             <>
               <div className="space-y-2">
-                <label className="text-sm font-medium">URL</label>
+                <label className="text-sm font-medium" htmlFor="sse-url-input">
+                  URL
+                </label>
                 <Input
+                  id="sse-url-input"
                   placeholder="URL"
                   value={sseUrl}
                   onChange={(e) => setSseUrl(e.target.value)}
@@ -140,6 +174,7 @@ const Sidebar = ({
                   variant="outline"
                   onClick={() => setShowBearerToken(!showBearerToken)}
                   className="flex items-center w-full"
+                  aria-expanded={showBearerToken}
                 >
                   {showBearerToken ? (
                     <ChevronDown className="w-4 h-4 mr-2" />
@@ -150,8 +185,14 @@ const Sidebar = ({
                 </Button>
                 {showBearerToken && (
                   <div className="space-y-2">
-                    <label className="text-sm font-medium">Bearer Token</label>
+                    <label
+                      className="text-sm font-medium"
+                      htmlFor="bearer-token-input"
+                    >
+                      Bearer Token
+                    </label>
                     <Input
+                      id="bearer-token-input"
                       placeholder="Bearer Token"
                       value={bearerToken}
                       onChange={(e) => setBearerToken(e.target.value)}
@@ -169,6 +210,8 @@ const Sidebar = ({
                 variant="outline"
                 onClick={() => setShowEnvVars(!showEnvVars)}
                 className="flex items-center w-full"
+                data-testid="env-vars-button"
+                aria-expanded={showEnvVars}
               >
                 {showEnvVars ? (
                   <ChevronDown className="w-4 h-4 mr-2" />
@@ -183,6 +226,7 @@ const Sidebar = ({
                     <div key={idx} className="space-y-2 pb-4">
                       <div className="flex gap-2">
                         <Input
+                          aria-label={`Environment variable key ${idx + 1}`}
                           placeholder="Key"
                           value={key}
                           onChange={(e) => {
@@ -225,6 +269,7 @@ const Sidebar = ({
                       </div>
                       <div className="flex gap-2">
                         <Input
+                          aria-label={`Environment variable value ${idx + 1}`}
                           type={shownEnvVars.has(key) ? "text" : "password"}
                           placeholder="Value"
                           value={value}
@@ -284,41 +329,177 @@ const Sidebar = ({
             </div>
           )}
 
+          {/* Configuration */}
           <div className="space-y-2">
+            <Button
+              variant="outline"
+              onClick={() => setShowConfig(!showConfig)}
+              className="flex items-center w-full"
+              data-testid="config-button"
+              aria-expanded={showConfig}
+            >
+              {showConfig ? (
+                <ChevronDown className="w-4 h-4 mr-2" />
+              ) : (
+                <ChevronRight className="w-4 h-4 mr-2" />
+              )}
+              <Settings className="w-4 h-4 mr-2" />
+              Configuration
+            </Button>
+            {showConfig && (
+              <div className="space-y-2">
+                {Object.entries(config).map(([key, configItem]) => {
+                  const configKey = key as keyof InspectorConfig;
+                  return (
+                    <div key={key} className="space-y-2">
+                      <div className="flex items-center gap-1">
+                        <label
+                          className="text-sm font-medium text-green-600 break-all"
+                          htmlFor={`${configKey}-input`}
+                        >
+                          {configItem.label}
+                        </label>
+                        <Tooltip>
+                          <TooltipTrigger asChild>
+                            <HelpCircle className="h-4 w-4 text-muted-foreground" />
+                          </TooltipTrigger>
+                          <TooltipContent>
+                            {configItem.description}
+                          </TooltipContent>
+                        </Tooltip>
+                      </div>
+                      {typeof configItem.value === "number" ? (
+                        <Input
+                          id={`${configKey}-input`}
+                          type="number"
+                          data-testid={`${configKey}-input`}
+                          value={configItem.value}
+                          onChange={(e) => {
+                            const newConfig = { ...config };
+                            newConfig[configKey] = {
+                              ...configItem,
+                              value: Number(e.target.value),
+                            };
+                            setConfig(newConfig);
+                          }}
+                          className="font-mono"
+                        />
+                      ) : typeof configItem.value === "boolean" ? (
+                        <Select
+                          data-testid={`${configKey}-select`}
+                          value={configItem.value.toString()}
+                          onValueChange={(val) => {
+                            const newConfig = { ...config };
+                            newConfig[configKey] = {
+                              ...configItem,
+                              value: val === "true",
+                            };
+                            setConfig(newConfig);
+                          }}
+                        >
+                          <SelectTrigger id={`${configKey}-input`}>
+                            <SelectValue />
+                          </SelectTrigger>
+                          <SelectContent>
+                            <SelectItem value="true">True</SelectItem>
+                            <SelectItem value="false">False</SelectItem>
+                          </SelectContent>
+                        </Select>
+                      ) : (
+                        <Input
+                          id={`${configKey}-input`}
+                          data-testid={`${configKey}-input`}
+                          value={configItem.value}
+                          onChange={(e) => {
+                            const newConfig = { ...config };
+                            newConfig[configKey] = {
+                              ...configItem,
+                              value: e.target.value,
+                            };
+                            setConfig(newConfig);
+                          }}
+                          className="font-mono"
+                        />
+                      )}
+                    </div>
+                  );
+                })}
+              </div>
+            )}
+          </div>
+
+          <div className="space-y-2">
+            {connectionStatus === "connected" && (
+              <div className="grid grid-cols-2 gap-4">
+                <Button
+                  data-testid="connect-button"
+                  onClick={() => {
+                    onDisconnect();
+                    onConnect();
+                  }}
+                >
+                  <RotateCcw className="w-4 h-4 mr-2" />
+                  {transportType === "stdio" ? "Restart" : "Reconnect"}
+                </Button>
+                <Button onClick={onDisconnect}>
+                  <RefreshCwOff className="w-4 h-4 mr-2" />
+                  Disconnect
+                </Button>
+              </div>
+            )}
+            {connectionStatus !== "connected" && (
               <Button className="w-full" onClick={onConnect}>
                 <Play className="w-4 h-4 mr-2" />
                 Connect
               </Button>
+            )}
 
             <div className="flex items-center justify-center space-x-2 mb-4">
               <div
-                className={`w-2 h-2 rounded-full ${
-                  connectionStatus === "connected"
-                    ? "bg-green-500"
-                    : connectionStatus === "error"
-                      ? "bg-red-500"
-                      : "bg-gray-500"
-                }`}
+                className={`w-2 h-2 rounded-full ${(() => {
+                  switch (connectionStatus) {
+                    case "connected":
+                      return "bg-green-500";
+                    case "error":
+                      return "bg-red-500";
+                    case "error-connecting-to-proxy":
+                      return "bg-red-500";
+                    default:
+                      return "bg-gray-500";
+                  }
+                })()}`}
               />
               <span className="text-sm text-gray-600">
-                {connectionStatus === "connected"
-                  ? "Connected"
-                  : connectionStatus === "error"
-                    ? "Connection Error"
-                    : "Disconnected"}
+                {(() => {
+                  switch (connectionStatus) {
+                    case "connected":
+                      return "Connected";
+                    case "error":
+                      return "Connection Error, is your MCP server running?";
+                    case "error-connecting-to-proxy":
+                      return "Error Connecting to MCP Inspector Proxy - Check Console logs";
+                    default:
+                      return "Disconnected";
+                  }
+                })()}
               </span>
             </div>
 
             {loggingSupported && connectionStatus === "connected" && (
               <div className="space-y-2">
-                <label className="text-sm font-medium">Logging Level</label>
+                <label
+                  className="text-sm font-medium"
+                  htmlFor="logging-level-select"
+                >
+                  Logging Level
+                </label>
                 <Select
                   value={logLevel}
                   onValueChange={(value: LoggingLevel) =>
                     sendLogLevelRequest(value)
                   }
                 >
-                  <SelectTrigger>
+                  <SelectTrigger id="logging-level-select">
                     <SelectValue placeholder="Select logging level" />
                   </SelectTrigger>
                   <SelectContent>
@@ -371,36 +552,37 @@ const Sidebar = ({
           </Select>
 
           <div className="flex items-center space-x-2">
+            <Button variant="ghost" title="Inspector Documentation" asChild>
               <a
                 href="https://modelcontextprotocol.io/docs/tools/inspector"
                 target="_blank"
                 rel="noopener noreferrer"
               >
-              <Button variant="ghost" title="Inspector Documentation">
-                <CircleHelp className="w-4 h-4 text-gray-800" />
-              </Button>
+                <CircleHelp className="w-4 h-4 text-foreground" />
               </a>
+            </Button>
+            <Button variant="ghost" title="Debugging Guide" asChild>
               <a
                 href="https://modelcontextprotocol.io/docs/tools/debugging"
                 target="_blank"
                 rel="noopener noreferrer"
               >
-              <Button variant="ghost" title="Debugging Guide">
-                <Bug className="w-4 h-4 text-gray-800" />
-              </Button>
+                <Bug className="w-4 h-4 text-foreground" />
               </a>
+            </Button>
+            <Button
+              variant="ghost"
+              title="Report bugs or contribute on GitHub"
+              asChild
+            >
               <a
                 href="https://github.com/modelcontextprotocol/inspector"
                 target="_blank"
                 rel="noopener noreferrer"
               >
-              <Button
-                variant="ghost"
-                title="Report bugs or contribute on GitHub"
-              >
-                <Github className="w-4 h-4 text-gray-800" />
-              </Button>
+                <Github className="w-4 h-4 text-foreground" />
               </a>
+            </Button>
           </div>
         </div>
       </div>

client/src/components/ToolsTab.tsx

@@ -1,11 +1,12 @@
-import { Alert, AlertDescription, AlertTitle } from "@/components/ui/alert";
+import { Alert, AlertDescription } from "@/components/ui/alert";
 import { Button } from "@/components/ui/button";
 import { Checkbox } from "@/components/ui/checkbox";
 import { Input } from "@/components/ui/input";
 import { Label } from "@/components/ui/label";
 import { TabsContent } from "@/components/ui/tabs";
 import { Textarea } from "@/components/ui/textarea";
-import DynamicJsonForm, { JsonSchemaType, JsonValue } from "./DynamicJsonForm";
+import DynamicJsonForm from "./DynamicJsonForm";
+import type { JsonValue, JsonSchemaType } from "@/utils/jsonUtils";
 import { generateDefaultValue } from "@/utils/schemaUtils";
 import {
   CallToolResultSchema,
@@ -13,10 +14,10 @@ import {
   ListToolsResult,
   Tool,
 } from "@modelcontextprotocol/sdk/types.js";
-import { AlertCircle, Send } from "lucide-react";
+import { Loader2, Send } from "lucide-react";
 import { useEffect, useState } from "react";
 import ListPane from "./ListPane";
-import { escapeUnicode } from "@/utils/escapeUnicode";
+import JsonView from "./JsonView";
 
 const ToolsTab = ({
   tools,
@@ -27,12 +28,11 @@ const ToolsTab = ({
   setSelectedTool,
   toolResult,
   nextCursor,
-  error,
 }: {
   tools: Tool[];
   listTools: () => void;
   clearTools: () => void;
-  callTool: (name: string, params: Record<string, unknown>) => void;
+  callTool: (name: string, params: Record<string, unknown>) => Promise<void>;
   selectedTool: Tool | null;
   setSelectedTool: (tool: Tool | null) => void;
   toolResult: CompatibilityCallToolResult | null;
@@ -40,6 +40,8 @@ const ToolsTab = ({
   error: string | null;
 }) => {
   const [params, setParams] = useState<Record<string, unknown>>({});
+  const [isToolRunning, setIsToolRunning] = useState(false);
+
   useEffect(() => {
     setParams({});
   }, [selectedTool]);
@@ -53,17 +55,10 @@ const ToolsTab = ({
         return (
           <>
             <h4 className="font-semibold mb-2">Invalid Tool Result:</h4>
-            <pre className="bg-gray-50 dark:bg-gray-800 dark:text-gray-100 p-4 rounded text-sm overflow-auto max-h-64">
-              {escapeUnicode(toolResult)}
-            </pre>
+            <JsonView data={toolResult} />
             <h4 className="font-semibold mb-2">Errors:</h4>
             {parsedResult.error.errors.map((error, idx) => (
-              <pre
-                key={idx}
-                className="bg-gray-50 dark:bg-gray-800 dark:text-gray-100 p-4 rounded text-sm overflow-auto max-h-64"
-              >
-                {escapeUnicode(error)}
-              </pre>
+              <JsonView data={error} key={idx} />
             ))}
           </>
         );
@@ -74,14 +69,17 @@ const ToolsTab = ({
       return (
         <>
           <h4 className="font-semibold mb-2">
-            Tool Result: {isError ? "Error" : "Success"}
+            Tool Result:{" "}
+            {isError ? (
+              <span className="text-red-600 font-semibold">Error</span>
+            ) : (
+              <span className="text-green-600 font-semibold">Success</span>
+            )}
           </h4>
           {structuredResult.content.map((item, index) => (
             <div key={index} className="mb-2">
               {item.type === "text" && (
-                <pre className="bg-gray-50 dark:bg-gray-800 dark:text-gray-100 p-4 rounded text-sm overflow-auto max-h-64">
-                  {item.text}
-                </pre>
+                <JsonView data={item.text} isError={isError} />
               )}
               {item.type === "image" && (
                 <img
@@ -100,9 +98,7 @@ const ToolsTab = ({
                     <p>Your browser does not support audio playback</p>
                   </audio>
                 ) : (
-                  <pre className="bg-gray-50 dark:bg-gray-800 dark:text-gray-100 whitespace-pre-wrap break-words p-4 rounded text-sm overflow-auto max-h-64">
-                    {escapeUnicode(item.resource)}
-                  </pre>
+                  <JsonView data={item.resource} />
                 ))}
             </div>
           ))}
@@ -112,16 +108,16 @@ const ToolsTab = ({
       return (
         <>
           <h4 className="font-semibold mb-2">Tool Result (Legacy):</h4>
-          <pre className="bg-gray-50 dark:bg-gray-800 dark:text-gray-100 p-4 rounded text-sm overflow-auto max-h-64">
-            {escapeUnicode(toolResult.toolResult)}
-          </pre>
+
+          <JsonView data={toolResult.toolResult} />
         </>
       );
     }
   };
 
   return (
-    <TabsContent value="tools" className="grid grid-cols-2 gap-4">
+    <TabsContent value="tools">
+      <div className="grid grid-cols-2 gap-4">
         <ListPane
           items={tools}
           listItems={listTools}
@@ -144,19 +140,13 @@ const ToolsTab = ({
         />
 
         <div className="bg-card rounded-lg shadow">
-        <div className="p-4 border-b border-gray-200">
+          <div className="p-4 border-b border-gray-200 dark:border-gray-800">
             <h3 className="font-semibold">
               {selectedTool ? selectedTool.name : "Select a tool"}
             </h3>
           </div>
           <div className="p-4">
-          {error ? (
-            <Alert variant="destructive">
-              <AlertCircle className="h-4 w-4" />
-              <AlertTitle>Error</AlertTitle>
-              <AlertDescription>{error}</AlertDescription>
-            </Alert>
-          ) : selectedTool ? (
+            {selectedTool ? (
               <div className="space-y-4">
                 <p className="text-sm text-gray-600">
                   {selectedTool.description}
@@ -229,7 +219,11 @@ const ToolsTab = ({
                           </div>
                         ) : (
                           <Input
-                          type={prop.type === "number" ? "number" : "text"}
+                            type={
+                              prop.type === "number" || prop.type === "integer"
+                                ? "number"
+                                : "text"
+                            }
                             id={key}
                             name={key}
                             placeholder={prop.description}
@@ -238,7 +232,8 @@ const ToolsTab = ({
                               setParams({
                                 ...params,
                                 [key]:
-                                prop.type === "number"
+                                  prop.type === "number" ||
+                                  prop.type === "integer"
                                     ? Number(e.target.value)
                                     : e.target.value,
                               })
@@ -250,9 +245,28 @@ const ToolsTab = ({
                     );
                   },
                 )}
-              <Button onClick={() => callTool(selectedTool.name, params)}>
+                <Button
+                  onClick={async () => {
+                    try {
+                      setIsToolRunning(true);
+                      await callTool(selectedTool.name, params);
+                    } finally {
+                      setIsToolRunning(false);
+                    }
+                  }}
+                  disabled={isToolRunning}
+                >
+                  {isToolRunning ? (
+                    <>
+                      <Loader2 className="w-4 h-4 mr-2 animate-spin" />
+                      Running...
+                    </>
+                  ) : (
+                    <>
                       <Send className="w-4 h-4 mr-2" />
                       Run Tool
+                    </>
+                  )}
                 </Button>
                 {toolResult && renderToolResult()}
               </div>
@@ -265,6 +279,7 @@ const ToolsTab = ({
             )}
           </div>
         </div>
+      </div>
     </TabsContent>
   );
 };

client/src/components/__tests__/DynamicJsonForm.test.tsx

@@ -0,0 +1,95 @@
+import { render, screen, fireEvent } from "@testing-library/react";
+import { describe, it, expect, jest } from "@jest/globals";
+import DynamicJsonForm from "../DynamicJsonForm";
+import type { JsonSchemaType } from "@/utils/jsonUtils";
+
+describe("DynamicJsonForm String Fields", () => {
+  const renderForm = (props = {}) => {
+    const defaultProps = {
+      schema: {
+        type: "string" as const,
+        description: "Test string field",
+      } satisfies JsonSchemaType,
+      value: undefined,
+      onChange: jest.fn(),
+    };
+    return render(<DynamicJsonForm {...defaultProps} {...props} />);
+  };
+
+  describe("Type Validation", () => {
+    it("should handle numeric input as string type", () => {
+      const onChange = jest.fn();
+      renderForm({ onChange });
+
+      const input = screen.getByRole("textbox");
+      fireEvent.change(input, { target: { value: "123321" } });
+
+      expect(onChange).toHaveBeenCalledWith("123321");
+      // Verify the value is a string, not a number
+      expect(typeof onChange.mock.calls[0][0]).toBe("string");
+    });
+
+    it("should render as text input, not number input", () => {
+      renderForm();
+      const input = screen.getByRole("textbox");
+      expect(input).toHaveProperty("type", "text");
+    });
+  });
+});
+
+describe("DynamicJsonForm Integer Fields", () => {
+  const renderForm = (props = {}) => {
+    const defaultProps = {
+      schema: {
+        type: "integer" as const,
+        description: "Test integer field",
+      } satisfies JsonSchemaType,
+      value: undefined,
+      onChange: jest.fn(),
+    };
+    return render(<DynamicJsonForm {...defaultProps} {...props} />);
+  };
+
+  describe("Basic Operations", () => {
+    it("should render number input with step=1", () => {
+      renderForm();
+      const input = screen.getByRole("spinbutton");
+      expect(input).toHaveProperty("type", "number");
+      expect(input).toHaveProperty("step", "1");
+    });
+
+    it("should pass integer values to onChange", () => {
+      const onChange = jest.fn();
+      renderForm({ onChange });
+
+      const input = screen.getByRole("spinbutton");
+      fireEvent.change(input, { target: { value: "42" } });
+
+      expect(onChange).toHaveBeenCalledWith(42);
+      // Verify the value is a number, not a string
+      expect(typeof onChange.mock.calls[0][0]).toBe("number");
+    });
+
+    it("should not pass string values to onChange", () => {
+      const onChange = jest.fn();
+      renderForm({ onChange });
+
+      const input = screen.getByRole("spinbutton");
+      fireEvent.change(input, { target: { value: "abc" } });
+
+      expect(onChange).not.toHaveBeenCalled();
+    });
+  });
+
+  describe("Edge Cases", () => {
+    it("should handle non-numeric input by not calling onChange", () => {
+      const onChange = jest.fn();
+      renderForm({ onChange });
+
+      const input = screen.getByRole("spinbutton");
+      fireEvent.change(input, { target: { value: "abc" } });
+
+      expect(onChange).not.toHaveBeenCalled();
+    });
+  });
+});

client/src/components/__tests__/Sidebar.test.tsx

@@ -0,0 +1,472 @@
+import { render, screen, fireEvent } from "@testing-library/react";
+import { describe, it, beforeEach, jest } from "@jest/globals";
+import Sidebar from "../Sidebar";
+import { DEFAULT_INSPECTOR_CONFIG } from "@/lib/constants";
+import { InspectorConfig } from "@/lib/configurationTypes";
+import { TooltipProvider } from "@/components/ui/tooltip";
+
+// Mock theme hook
+jest.mock("../../lib/useTheme", () => ({
+  __esModule: true,
+  default: () => ["light", jest.fn()],
+}));
+
+describe("Sidebar Environment Variables", () => {
+  const defaultProps = {
+    connectionStatus: "disconnected" as const,
+    transportType: "stdio" as const,
+    setTransportType: jest.fn(),
+    command: "",
+    setCommand: jest.fn(),
+    args: "",
+    setArgs: jest.fn(),
+    sseUrl: "",
+    setSseUrl: jest.fn(),
+    env: {},
+    setEnv: jest.fn(),
+    bearerToken: "",
+    setBearerToken: jest.fn(),
+    onConnect: jest.fn(),
+    onDisconnect: jest.fn(),
+    stdErrNotifications: [],
+    logLevel: "info" as const,
+    sendLogLevelRequest: jest.fn(),
+    loggingSupported: true,
+    config: DEFAULT_INSPECTOR_CONFIG,
+    setConfig: jest.fn(),
+  };
+
+  const renderSidebar = (props = {}) => {
+    return render(
+      <TooltipProvider>
+        <Sidebar {...defaultProps} {...props} />
+      </TooltipProvider>,
+    );
+  };
+
+  const openEnvVarsSection = () => {
+    const button = screen.getByTestId("env-vars-button");
+    fireEvent.click(button);
+  };
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  describe("Basic Operations", () => {
+    it("should add a new environment variable", () => {
+      const setEnv = jest.fn();
+      renderSidebar({ env: {}, setEnv });
+
+      openEnvVarsSection();
+
+      const addButton = screen.getByText("Add Environment Variable");
+      fireEvent.click(addButton);
+
+      expect(setEnv).toHaveBeenCalledWith({ "": "" });
+    });
+
+    it("should remove an environment variable", () => {
+      const setEnv = jest.fn();
+      const initialEnv = { TEST_KEY: "test_value" };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      const removeButton = screen.getByRole("button", { name: "×" });
+      fireEvent.click(removeButton);
+
+      expect(setEnv).toHaveBeenCalledWith({});
+    });
+
+    it("should update environment variable value", () => {
+      const setEnv = jest.fn();
+      const initialEnv = { TEST_KEY: "test_value" };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      const valueInput = screen.getByDisplayValue("test_value");
+      fireEvent.change(valueInput, { target: { value: "new_value" } });
+
+      expect(setEnv).toHaveBeenCalledWith({ TEST_KEY: "new_value" });
+    });
+
+    it("should toggle value visibility", () => {
+      const initialEnv = { TEST_KEY: "test_value" };
+      renderSidebar({ env: initialEnv });
+
+      openEnvVarsSection();
+
+      const valueInput = screen.getByDisplayValue("test_value");
+      expect(valueInput).toHaveProperty("type", "password");
+
+      const toggleButton = screen.getByRole("button", { name: /show value/i });
+      fireEvent.click(toggleButton);
+
+      expect(valueInput).toHaveProperty("type", "text");
+    });
+  });
+
+  describe("Key Editing", () => {
+    it("should maintain order when editing first key", () => {
+      const setEnv = jest.fn();
+      const initialEnv = {
+        FIRST_KEY: "first_value",
+        SECOND_KEY: "second_value",
+        THIRD_KEY: "third_value",
+      };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      const firstKeyInput = screen.getByDisplayValue("FIRST_KEY");
+      fireEvent.change(firstKeyInput, { target: { value: "NEW_FIRST_KEY" } });
+
+      expect(setEnv).toHaveBeenCalledWith({
+        NEW_FIRST_KEY: "first_value",
+        SECOND_KEY: "second_value",
+        THIRD_KEY: "third_value",
+      });
+    });
+
+    it("should maintain order when editing middle key", () => {
+      const setEnv = jest.fn();
+      const initialEnv = {
+        FIRST_KEY: "first_value",
+        SECOND_KEY: "second_value",
+        THIRD_KEY: "third_value",
+      };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      const middleKeyInput = screen.getByDisplayValue("SECOND_KEY");
+      fireEvent.change(middleKeyInput, { target: { value: "NEW_SECOND_KEY" } });
+
+      expect(setEnv).toHaveBeenCalledWith({
+        FIRST_KEY: "first_value",
+        NEW_SECOND_KEY: "second_value",
+        THIRD_KEY: "third_value",
+      });
+    });
+
+    it("should maintain order when editing last key", () => {
+      const setEnv = jest.fn();
+      const initialEnv = {
+        FIRST_KEY: "first_value",
+        SECOND_KEY: "second_value",
+        THIRD_KEY: "third_value",
+      };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      const lastKeyInput = screen.getByDisplayValue("THIRD_KEY");
+      fireEvent.change(lastKeyInput, { target: { value: "NEW_THIRD_KEY" } });
+
+      expect(setEnv).toHaveBeenCalledWith({
+        FIRST_KEY: "first_value",
+        SECOND_KEY: "second_value",
+        NEW_THIRD_KEY: "third_value",
+      });
+    });
+
+    it("should maintain order during key editing", () => {
+      const setEnv = jest.fn();
+      const initialEnv = {
+        KEY1: "value1",
+        KEY2: "value2",
+      };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      // Type "NEW_" one character at a time
+      const key1Input = screen.getByDisplayValue("KEY1");
+      "NEW_".split("").forEach((char) => {
+        fireEvent.change(key1Input, {
+          target: { value: char + "KEY1".slice(1) },
+        });
+      });
+
+      // Verify the last setEnv call maintains the order
+      const lastCall = setEnv.mock.calls[
+        setEnv.mock.calls.length - 1
+      ][0] as Record<string, string>;
+      const entries = Object.entries(lastCall);
+
+      // The values should stay with their original keys
+      expect(entries[0][1]).toBe("value1"); // First entry should still have value1
+      expect(entries[1][1]).toBe("value2"); // Second entry should still have value2
+    });
+  });
+
+  describe("Multiple Operations", () => {
+    it("should maintain state after multiple key edits", () => {
+      const setEnv = jest.fn();
+      const initialEnv = {
+        FIRST_KEY: "first_value",
+        SECOND_KEY: "second_value",
+      };
+      const { rerender } = renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      // First key edit
+      const firstKeyInput = screen.getByDisplayValue("FIRST_KEY");
+      fireEvent.change(firstKeyInput, { target: { value: "NEW_FIRST_KEY" } });
+
+      // Get the updated env from the first setEnv call
+      const updatedEnv = setEnv.mock.calls[0][0] as Record<string, string>;
+
+      // Rerender with the updated env
+      rerender(
+        <TooltipProvider>
+          <Sidebar {...defaultProps} env={updatedEnv} setEnv={setEnv} />
+        </TooltipProvider>,
+      );
+
+      // Second key edit
+      const secondKeyInput = screen.getByDisplayValue("SECOND_KEY");
+      fireEvent.change(secondKeyInput, { target: { value: "NEW_SECOND_KEY" } });
+
+      // Verify the final state matches what we expect
+      expect(setEnv).toHaveBeenLastCalledWith({
+        NEW_FIRST_KEY: "first_value",
+        NEW_SECOND_KEY: "second_value",
+      });
+    });
+
+    it("should maintain visibility state after key edit", () => {
+      const initialEnv = { TEST_KEY: "test_value" };
+      const { rerender } = renderSidebar({ env: initialEnv });
+
+      openEnvVarsSection();
+
+      // Show the value
+      const toggleButton = screen.getByRole("button", { name: /show value/i });
+      fireEvent.click(toggleButton);
+
+      const valueInput = screen.getByDisplayValue("test_value");
+      expect(valueInput).toHaveProperty("type", "text");
+
+      // Edit the key
+      const keyInput = screen.getByDisplayValue("TEST_KEY");
+      fireEvent.change(keyInput, { target: { value: "NEW_KEY" } });
+
+      // Rerender with updated env
+      rerender(
+        <TooltipProvider>
+          <Sidebar {...defaultProps} env={{ NEW_KEY: "test_value" }} />
+        </TooltipProvider>,
+      );
+
+      // Value should still be visible
+      const updatedValueInput = screen.getByDisplayValue("test_value");
+      expect(updatedValueInput).toHaveProperty("type", "text");
+    });
+  });
+
+  describe("Edge Cases", () => {
+    it("should handle empty key", () => {
+      const setEnv = jest.fn();
+      const initialEnv = { TEST_KEY: "test_value" };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      const keyInput = screen.getByDisplayValue("TEST_KEY");
+      fireEvent.change(keyInput, { target: { value: "" } });
+
+      expect(setEnv).toHaveBeenCalledWith({ "": "test_value" });
+    });
+
+    it("should handle special characters in key", () => {
+      const setEnv = jest.fn();
+      const initialEnv = { TEST_KEY: "test_value" };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      const keyInput = screen.getByDisplayValue("TEST_KEY");
+      fireEvent.change(keyInput, { target: { value: "TEST-KEY@123" } });
+
+      expect(setEnv).toHaveBeenCalledWith({ "TEST-KEY@123": "test_value" });
+    });
+
+    it("should handle unicode characters", () => {
+      const setEnv = jest.fn();
+      const initialEnv = { TEST_KEY: "test_value" };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      const keyInput = screen.getByDisplayValue("TEST_KEY");
+      fireEvent.change(keyInput, { target: { value: "TEST_🔑" } });
+
+      expect(setEnv).toHaveBeenCalledWith({ "TEST_🔑": "test_value" });
+    });
+
+    it("should handle very long key names", () => {
+      const setEnv = jest.fn();
+      const initialEnv = { TEST_KEY: "test_value" };
+      renderSidebar({ env: initialEnv, setEnv });
+
+      openEnvVarsSection();
+
+      const keyInput = screen.getByDisplayValue("TEST_KEY");
+      const longKey = "A".repeat(100);
+      fireEvent.change(keyInput, { target: { value: longKey } });
+
+      expect(setEnv).toHaveBeenCalledWith({ [longKey]: "test_value" });
+    });
+  });
+
+  describe("Configuration Operations", () => {
+    const openConfigSection = () => {
+      const button = screen.getByTestId("config-button");
+      fireEvent.click(button);
+    };
+
+    it("should update MCP server request timeout", () => {
+      const setConfig = jest.fn();
+      renderSidebar({ config: DEFAULT_INSPECTOR_CONFIG, setConfig });
+
+      openConfigSection();
+
+      const timeoutInput = screen.getByTestId(
+        "MCP_SERVER_REQUEST_TIMEOUT-input",
+      );
+      fireEvent.change(timeoutInput, { target: { value: "5000" } });
+
+      expect(setConfig).toHaveBeenCalledWith(
+        expect.objectContaining({
+          MCP_SERVER_REQUEST_TIMEOUT: {
+            label: "Request Timeout",
+            description: "Timeout for requests to the MCP server (ms)",
+            value: 5000,
+          },
+        }),
+      );
+    });
+
+    it("should update MCP server proxy address", () => {
+      const setConfig = jest.fn();
+      renderSidebar({ config: DEFAULT_INSPECTOR_CONFIG, setConfig });
+
+      openConfigSection();
+
+      const proxyAddressInput = screen.getByTestId(
+        "MCP_PROXY_FULL_ADDRESS-input",
+      );
+      fireEvent.change(proxyAddressInput, {
+        target: { value: "http://localhost:8080" },
+      });
+
+      expect(setConfig).toHaveBeenCalledWith(
+        expect.objectContaining({
+          MCP_PROXY_FULL_ADDRESS: {
+            label: "Inspector Proxy Address",
+            description:
+              "Set this if you are running the MCP Inspector Proxy on a non-default address. Example: http://10.1.1.22:5577",
+            value: "http://localhost:8080",
+          },
+        }),
+      );
+    });
+
+    it("should update max total timeout", () => {
+      const setConfig = jest.fn();
+      renderSidebar({ config: DEFAULT_INSPECTOR_CONFIG, setConfig });
+
+      openConfigSection();
+
+      const maxTotalTimeoutInput = screen.getByTestId(
+        "MCP_REQUEST_MAX_TOTAL_TIMEOUT-input",
+      );
+      fireEvent.change(maxTotalTimeoutInput, {
+        target: { value: "10000" },
+      });
+
+      expect(setConfig).toHaveBeenCalledWith(
+        expect.objectContaining({
+          MCP_REQUEST_MAX_TOTAL_TIMEOUT: {
+            label: "Maximum Total Timeout",
+            description:
+              "Maximum total timeout for requests sent to the MCP server (ms) (Use with progress notifications)",
+            value: 10000,
+          },
+        }),
+      );
+    });
+
+    it("should handle invalid timeout values entered by user", () => {
+      const setConfig = jest.fn();
+      renderSidebar({ config: DEFAULT_INSPECTOR_CONFIG, setConfig });
+
+      openConfigSection();
+
+      const timeoutInput = screen.getByTestId(
+        "MCP_SERVER_REQUEST_TIMEOUT-input",
+      );
+      fireEvent.change(timeoutInput, { target: { value: "abc1" } });
+
+      expect(setConfig).toHaveBeenCalledWith(
+        expect.objectContaining({
+          MCP_SERVER_REQUEST_TIMEOUT: {
+            label: "Request Timeout",
+            description: "Timeout for requests to the MCP server (ms)",
+            value: 0,
+          },
+        }),
+      );
+    });
+
+    it("should maintain configuration state after multiple updates", () => {
+      const setConfig = jest.fn();
+      const { rerender } = renderSidebar({
+        config: DEFAULT_INSPECTOR_CONFIG,
+        setConfig,
+      });
+
+      openConfigSection();
+      // First update
+      const timeoutInput = screen.getByTestId(
+        "MCP_SERVER_REQUEST_TIMEOUT-input",
+      );
+      fireEvent.change(timeoutInput, { target: { value: "5000" } });
+
+      // Get the updated config from the first setConfig call
+      const updatedConfig = setConfig.mock.calls[0][0] as InspectorConfig;
+
+      // Rerender with the updated config
+      rerender(
+        <TooltipProvider>
+          <Sidebar
+            {...defaultProps}
+            config={updatedConfig}
+            setConfig={setConfig}
+          />
+        </TooltipProvider>,
+      );
+
+      // Second update
+      const updatedTimeoutInput = screen.getByTestId(
+        "MCP_SERVER_REQUEST_TIMEOUT-input",
+      );
+      fireEvent.change(updatedTimeoutInput, { target: { value: "3000" } });
+
+      // Verify the final state matches what we expect
+      expect(setConfig).toHaveBeenLastCalledWith(
+        expect.objectContaining({
+          MCP_SERVER_REQUEST_TIMEOUT: {
+            label: "Request Timeout",
+            description: "Timeout for requests to the MCP server (ms)",
+            value: 3000,
+          },
+        }),
+      );
+    });
+  });
+});

client/src/components/__tests__/ToolsTab.test.tsx

@@ -0,0 +1,144 @@
+import { render, screen, fireEvent, act } from "@testing-library/react";
+import { describe, it, expect, jest } from "@jest/globals";
+import "@testing-library/jest-dom";
+import ToolsTab from "../ToolsTab";
+import { Tool } from "@modelcontextprotocol/sdk/types.js";
+import { Tabs } from "@/components/ui/tabs";
+
+describe("ToolsTab", () => {
+  const mockTools: Tool[] = [
+    {
+      name: "tool1",
+      description: "First tool",
+      inputSchema: {
+        type: "object" as const,
+        properties: {
+          num: { type: "number" as const },
+        },
+      },
+    },
+    {
+      name: "tool3",
+      description: "Integer tool",
+      inputSchema: {
+        type: "object" as const,
+        properties: {
+          count: { type: "integer" as const },
+        },
+      },
+    },
+    {
+      name: "tool2",
+      description: "Second tool",
+      inputSchema: {
+        type: "object" as const,
+        properties: {
+          num: { type: "number" as const },
+        },
+      },
+    },
+  ];
+
+  const defaultProps = {
+    tools: mockTools,
+    listTools: jest.fn(),
+    clearTools: jest.fn(),
+    callTool: jest.fn(async () => {}),
+    selectedTool: null,
+    setSelectedTool: jest.fn(),
+    toolResult: null,
+    nextCursor: "",
+    error: null,
+  };
+
+  const renderToolsTab = (props = {}) => {
+    return render(
+      <Tabs defaultValue="tools">
+        <ToolsTab {...defaultProps} {...props} />
+      </Tabs>,
+    );
+  };
+
+  it("should reset input values when switching tools", async () => {
+    const { rerender } = renderToolsTab({
+      selectedTool: mockTools[0],
+    });
+
+    // Enter a value in the first tool's input
+    const input = screen.getByRole("spinbutton") as HTMLInputElement;
+    await act(async () => {
+      fireEvent.change(input, { target: { value: "42" } });
+    });
+    expect(input.value).toBe("42");
+
+    // Switch to second tool
+    rerender(
+      <Tabs defaultValue="tools">
+        <ToolsTab {...defaultProps} selectedTool={mockTools[2]} />
+      </Tabs>,
+    );
+
+    // Verify input is reset
+    const newInput = screen.getByRole("spinbutton") as HTMLInputElement;
+    expect(newInput.value).toBe("");
+  });
+
+  it("should handle integer type inputs", async () => {
+    renderToolsTab({
+      selectedTool: mockTools[1], // Use the tool with integer type
+    });
+
+    const input = screen.getByRole("spinbutton", {
+      name: /count/i,
+    }) as HTMLInputElement;
+    expect(input).toHaveProperty("type", "number");
+    fireEvent.change(input, { target: { value: "42" } });
+    expect(input.value).toBe("42");
+
+    const submitButton = screen.getByRole("button", { name: /run tool/i });
+    await act(async () => {
+      fireEvent.click(submitButton);
+    });
+
+    expect(defaultProps.callTool).toHaveBeenCalledWith(mockTools[1].name, {
+      count: 42,
+    });
+  });
+
+  it("should disable button and change text while tool is running", async () => {
+    // Create a promise that we can resolve later
+    let resolvePromise: ((value: unknown) => void) | undefined;
+    const mockPromise = new Promise((resolve) => {
+      resolvePromise = resolve;
+    });
+
+    // Mock callTool to return our promise
+    const mockCallTool = jest.fn().mockReturnValue(mockPromise);
+
+    renderToolsTab({
+      selectedTool: mockTools[0],
+      callTool: mockCallTool,
+    });
+
+    const submitButton = screen.getByRole("button", { name: /run tool/i });
+    expect(submitButton.getAttribute("disabled")).toBeNull();
+
+    // Click the button and verify immediate state changes
+    await act(async () => {
+      fireEvent.click(submitButton);
+    });
+
+    // Verify button is disabled and text changed
+    expect(submitButton.getAttribute("disabled")).not.toBeNull();
+    expect(submitButton.textContent).toBe("Running...");
+
+    // Resolve the promise to simulate tool completion
+    await act(async () => {
+      if (resolvePromise) {
+        await resolvePromise({});
+      }
+    });
+
+    expect(submitButton.getAttribute("disabled")).toBeNull();
+  });
+});

client/src/components/ui/button.tsx

@@ -54,4 +54,4 @@ const Button = React.forwardRef<HTMLButtonElement, ButtonProps>(
 );
 Button.displayName = "Button";
 
-export { Button, buttonVariants };
+export { Button };

client/src/components/ui/input.tsx

@@ -2,8 +2,7 @@ import * as React from "react";
 
 import { cn } from "@/lib/utils";
 
-export interface InputProps
-  extends React.InputHTMLAttributes<HTMLInputElement> {}
+export type InputProps = React.InputHTMLAttributes<HTMLInputElement>;
 
 const Input = React.forwardRef<HTMLInputElement, InputProps>(
   ({ className, type, ...props }, ref) => {

client/src/components/ui/select.tsx

@@ -22,7 +22,7 @@ const SelectTrigger = React.forwardRef<
   <SelectPrimitive.Trigger
     ref={ref}
     className={cn(
-      "flex h-9 w-full items-center justify-between whitespace-nowrap rounded-md border border-input bg-transparent px-3 py-2 text-sm shadow-sm ring-offset-background placeholder:text-muted-foreground focus:outline-none focus:ring-1 focus:ring-ring disabled:cursor-not-allowed disabled:opacity-50 [&>span]:line-clamp-1",
+      "flex h-9 w-full items-center justify-between whitespace-nowrap rounded-md border border-input bg-transparent px-3 py-2 text-sm shadow-sm ring-offset-background placeholder:text-muted-foreground focus:outline-none focus:ring-1 focus:ring-ring disabled:cursor-not-allowed disabled:opacity-50 [&>span]:line-clamp-1 hover:border-[#646cff] hover:border-1",
       className,
     )}
     {...props}

client/src/components/ui/textarea.tsx

@@ -2,8 +2,7 @@ import * as React from "react";
 
 import { cn } from "@/lib/utils";
 
-export interface TextareaProps
-  extends React.TextareaHTMLAttributes<HTMLTextAreaElement> {}
+export type TextareaProps = React.TextareaHTMLAttributes<HTMLTextAreaElement>;
 
 const Textarea = React.forwardRef<HTMLTextAreaElement, TextareaProps>(
   ({ className, ...props }, ref) => {

client/src/components/ui/toast.tsx

@@ -0,0 +1,126 @@
+import * as React from "react";
+import * as ToastPrimitives from "@radix-ui/react-toast";
+import { cva, type VariantProps } from "class-variance-authority";
+import { cn } from "@/lib/utils";
+import { Cross2Icon } from "@radix-ui/react-icons";
+
+const ToastProvider = ToastPrimitives.Provider;
+
+const ToastViewport = React.forwardRef<
+  React.ElementRef<typeof ToastPrimitives.Viewport>,
+  React.ComponentPropsWithoutRef<typeof ToastPrimitives.Viewport>
+>(({ className, ...props }, ref) => (
+  <ToastPrimitives.Viewport
+    ref={ref}
+    className={cn(
+      "fixed top-0 z-[100] flex max-h-screen w-full flex-col-reverse p-4 sm:bottom-0 sm:right-0 sm:top-auto sm:flex-col md:max-w-[420px]",
+      className,
+    )}
+    {...props}
+  />
+));
+ToastViewport.displayName = ToastPrimitives.Viewport.displayName;
+
+const toastVariants = cva(
+  "group pointer-events-auto relative flex w-full items-center justify-between space-x-2 overflow-hidden rounded-md border p-4 pr-6 shadow-lg transition-all data-[swipe=cancel]:translate-x-0 data-[swipe=end]:translate-x-[var(--radix-toast-swipe-end-x)] data-[swipe=move]:translate-x-[var(--radix-toast-swipe-move-x)] data-[swipe=move]:transition-none data-[state=open]:animate-in data-[state=closed]:animate-out data-[swipe=end]:animate-out data-[state=closed]:fade-out-80 data-[state=closed]:slide-out-to-right-full data-[state=open]:slide-in-from-top-full data-[state=open]:sm:slide-in-from-bottom-full",
+  {
+    variants: {
+      variant: {
+        default: "border bg-background text-foreground",
+        destructive:
+          "destructive group border-destructive bg-destructive text-destructive-foreground",
+      },
+    },
+    defaultVariants: {
+      variant: "default",
+    },
+  },
+);
+
+const Toast = React.forwardRef<
+  React.ElementRef<typeof ToastPrimitives.Root>,
+  React.ComponentPropsWithoutRef<typeof ToastPrimitives.Root> &
+    VariantProps<typeof toastVariants>
+>(({ className, variant, ...props }, ref) => {
+  return (
+    <ToastPrimitives.Root
+      ref={ref}
+      className={cn(toastVariants({ variant }), className)}
+      {...props}
+    />
+  );
+});
+Toast.displayName = ToastPrimitives.Root.displayName;
+
+const ToastAction = React.forwardRef<
+  React.ElementRef<typeof ToastPrimitives.Action>,
+  React.ComponentPropsWithoutRef<typeof ToastPrimitives.Action>
+>(({ className, ...props }, ref) => (
+  <ToastPrimitives.Action
+    ref={ref}
+    className={cn(
+      "inline-flex h-8 shrink-0 items-center justify-center rounded-md border bg-transparent px-3 text-sm font-medium transition-colors hover:bg-secondary focus:outline-none focus:ring-1 focus:ring-ring disabled:pointer-events-none disabled:opacity-50 group-[.destructive]:border-muted/40 group-[.destructive]:hover:border-destructive/30 group-[.destructive]:hover:bg-destructive group-[.destructive]:hover:text-destructive-foreground group-[.destructive]:focus:ring-destructive",
+      className,
+    )}
+    {...props}
+  />
+));
+ToastAction.displayName = ToastPrimitives.Action.displayName;
+
+const ToastClose = React.forwardRef<
+  React.ElementRef<typeof ToastPrimitives.Close>,
+  React.ComponentPropsWithoutRef<typeof ToastPrimitives.Close>
+>(({ className, ...props }, ref) => (
+  <ToastPrimitives.Close
+    ref={ref}
+    className={cn(
+      "absolute right-1 top-1 rounded-md p-1 text-foreground/50 opacity-0 transition-opacity hover:text-foreground focus:opacity-100 focus:outline-none focus:ring-1 group-hover:opacity-100 group-[.destructive]:text-red-300 group-[.destructive]:hover:text-red-50 group-[.destructive]:focus:ring-red-400 group-[.destructive]:focus:ring-offset-red-600",
+      className,
+    )}
+    toast-close=""
+    {...props}
+  >
+    <Cross2Icon className="h-4 w-4" />
+  </ToastPrimitives.Close>
+));
+ToastClose.displayName = ToastPrimitives.Close.displayName;
+
+const ToastTitle = React.forwardRef<
+  React.ElementRef<typeof ToastPrimitives.Title>,
+  React.ComponentPropsWithoutRef<typeof ToastPrimitives.Title>
+>(({ className, ...props }, ref) => (
+  <ToastPrimitives.Title
+    ref={ref}
+    className={cn("text-sm font-semibold [&+div]:text-xs", className)}
+    {...props}
+  />
+));
+ToastTitle.displayName = ToastPrimitives.Title.displayName;
+
+const ToastDescription = React.forwardRef<
+  React.ElementRef<typeof ToastPrimitives.Description>,
+  React.ComponentPropsWithoutRef<typeof ToastPrimitives.Description>
+>(({ className, ...props }, ref) => (
+  <ToastPrimitives.Description
+    ref={ref}
+    className={cn("text-sm opacity-90", className)}
+    {...props}
+  />
+));
+ToastDescription.displayName = ToastPrimitives.Description.displayName;
+
+type ToastProps = React.ComponentPropsWithoutRef<typeof Toast>;
+
+type ToastActionElement = React.ReactElement<typeof ToastAction>;
+
+export {
+  type ToastProps,
+  type ToastActionElement,
+  ToastProvider,
+  ToastViewport,
+  Toast,
+  ToastTitle,
+  ToastDescription,
+  ToastClose,
+  ToastAction,
+};

client/src/components/ui/toaster.tsx

@@ -0,0 +1,33 @@
+import { useToast } from "@/hooks/use-toast";
+import {
+  Toast,
+  ToastClose,
+  ToastDescription,
+  ToastProvider,
+  ToastTitle,
+  ToastViewport,
+} from "@/components/ui/toast";
+
+export function Toaster() {
+  const { toasts } = useToast();
+
+  return (
+    <ToastProvider>
+      {toasts.map(function ({ id, title, description, action, ...props }) {
+        return (
+          <Toast key={id} {...props}>
+            <div className="grid gap-1">
+              {title && <ToastTitle>{title}</ToastTitle>}
+              {description && (
+                <ToastDescription>{description}</ToastDescription>
+              )}
+            </div>
+            {action}
+            <ToastClose />
+          </Toast>
+        );
+      })}
+      <ToastViewport />
+    </ToastProvider>
+  );
+}

client/src/components/ui/tooltip.tsx

@@ -0,0 +1,30 @@
+"use client";
+
+import * as React from "react";
+import * as TooltipPrimitive from "@radix-ui/react-tooltip";
+
+import { cn } from "@/lib/utils";
+
+const TooltipProvider = TooltipPrimitive.Provider;
+
+const Tooltip = TooltipPrimitive.Root;
+
+const TooltipTrigger = TooltipPrimitive.Trigger;
+
+const TooltipContent = React.forwardRef<
+  React.ElementRef<typeof TooltipPrimitive.Content>,
+  React.ComponentPropsWithoutRef<typeof TooltipPrimitive.Content>
+>(({ className, sideOffset = 4, ...props }, ref) => (
+  <TooltipPrimitive.Content
+    ref={ref}
+    sideOffset={sideOffset}
+    className={cn(
+      "z-50 overflow-hidden rounded-md border bg-popover px-3 py-1.5 text-sm text-popover-foreground shadow-md animate-in fade-in-0 zoom-in-95 data-[state=closed]:animate-out data-[state=closed]:fade-out-0 data-[state=closed]:zoom-out-95 data-[side=bottom]:slide-in-from-top-2 data-[side=left]:slide-in-from-right-2 data-[side=right]:slide-in-from-left-2 data-[side=top]:slide-in-from-bottom-2 origin-[--radix-tooltip-content-transform-origin]",
+      className,
+    )}
+    {...props}
+  />
+));
+TooltipContent.displayName = TooltipPrimitive.Content.displayName;
+
+export { Tooltip, TooltipTrigger, TooltipContent, TooltipProvider };

client/src/hooks/use-toast.ts

@@ -0,0 +1,191 @@
+"use client";
+
+// Inspired by react-hot-toast library
+import * as React from "react";
+
+import type { ToastActionElement, ToastProps } from "@/components/ui/toast";
+
+const TOAST_LIMIT = 1;
+const TOAST_REMOVE_DELAY = 1000000;
+
+type ToasterToast = ToastProps & {
+  id: string;
+  title?: React.ReactNode;
+  description?: React.ReactNode;
+  action?: ToastActionElement;
+};
+
+let count = 0;
+
+function genId() {
+  count = (count + 1) % Number.MAX_SAFE_INTEGER;
+  return count.toString();
+}
+
+const enum ActionType {
+  ADD_TOAST = "ADD_TOAST",
+  UPDATE_TOAST = "UPDATE_TOAST",
+  DISMISS_TOAST = "DISMISS_TOAST",
+  REMOVE_TOAST = "REMOVE_TOAST",
+}
+
+type Action =
+  | {
+      type: ActionType.ADD_TOAST;
+      toast: ToasterToast;
+    }
+  | {
+      type: ActionType.UPDATE_TOAST;
+      toast: Partial<ToasterToast>;
+    }
+  | {
+      type: ActionType.DISMISS_TOAST;
+      toastId?: ToasterToast["id"];
+    }
+  | {
+      type: ActionType.REMOVE_TOAST;
+      toastId?: ToasterToast["id"];
+    };
+
+interface State {
+  toasts: ToasterToast[];
+}
+
+const toastTimeouts = new Map<string, ReturnType<typeof setTimeout>>();
+
+const addToRemoveQueue = (toastId: string) => {
+  if (toastTimeouts.has(toastId)) {
+    return;
+  }
+
+  const timeout = setTimeout(() => {
+    toastTimeouts.delete(toastId);
+    dispatch({
+      type: ActionType.REMOVE_TOAST,
+      toastId: toastId,
+    });
+  }, TOAST_REMOVE_DELAY);
+
+  toastTimeouts.set(toastId, timeout);
+};
+
+export const reducer = (state: State, action: Action): State => {
+  switch (action.type) {
+    case ActionType.ADD_TOAST:
+      return {
+        ...state,
+        toasts: [action.toast, ...state.toasts].slice(0, TOAST_LIMIT),
+      };
+
+    case ActionType.UPDATE_TOAST:
+      return {
+        ...state,
+        toasts: state.toasts.map((t) =>
+          t.id === action.toast.id ? { ...t, ...action.toast } : t,
+        ),
+      };
+
+    case ActionType.DISMISS_TOAST: {
+      const { toastId } = action;
+
+      // ! Side effects ! - This could be extracted into a dismissToast() action,
+      // but I'll keep it here for simplicity
+      if (toastId) {
+        addToRemoveQueue(toastId);
+      } else {
+        state.toasts.forEach((toast) => {
+          addToRemoveQueue(toast.id);
+        });
+      }
+
+      return {
+        ...state,
+        toasts: state.toasts.map((t) =>
+          t.id === toastId || toastId === undefined
+            ? {
+                ...t,
+                open: false,
+              }
+            : t,
+        ),
+      };
+    }
+    case ActionType.REMOVE_TOAST:
+      if (action.toastId === undefined) {
+        return {
+          ...state,
+          toasts: [],
+        };
+      }
+      return {
+        ...state,
+        toasts: state.toasts.filter((t) => t.id !== action.toastId),
+      };
+  }
+};
+
+const listeners: Array<(state: State) => void> = [];
+
+let memoryState: State = { toasts: [] };
+
+function dispatch(action: Action) {
+  memoryState = reducer(memoryState, action);
+  listeners.forEach((listener) => {
+    listener(memoryState);
+  });
+}
+
+type Toast = Omit<ToasterToast, "id">;
+
+function toast({ ...props }: Toast) {
+  const id = genId();
+
+  const update = (props: ToasterToast) =>
+    dispatch({
+      type: ActionType.UPDATE_TOAST,
+      toast: { ...props, id },
+    });
+  const dismiss = () =>
+    dispatch({ type: ActionType.DISMISS_TOAST, toastId: id });
+
+  dispatch({
+    type: ActionType.ADD_TOAST,
+    toast: {
+      ...props,
+      id,
+      open: true,
+      onOpenChange: (open) => {
+        if (!open) dismiss();
+      },
+    },
+  });
+
+  return {
+    id: id,
+    dismiss,
+    update,
+  };
+}
+
+function useToast() {
+  const [state, setState] = React.useState<State>(memoryState);
+
+  React.useEffect(() => {
+    listeners.push(setState);
+    return () => {
+      const index = listeners.indexOf(setState);
+      if (index > -1) {
+        listeners.splice(index, 1);
+      }
+    };
+  }, [state]);
+
+  return {
+    ...state,
+    toast,
+    dismiss: (toastId?: string) =>
+      dispatch({ type: ActionType.DISMISS_TOAST, toastId }),
+  };
+}
+
+export { useToast, toast };

client/src/index.css

@@ -38,29 +38,6 @@ h1 {
   line-height: 1.1;
 }
 
-button {
-  border-radius: 8px;
-  border: 1px solid transparent;
-  padding: 0.6em 1.2em;
-  font-size: 1em;
-  font-weight: 500;
-  font-family: inherit;
-  background-color: #1a1a1a;
-  cursor: pointer;
-  transition: border-color 0.25s;
-}
-button:hover {
-  border-color: #646cff;
-}
-button:focus,
-button:focus-visible {
-  outline: 4px auto -webkit-focus-ring-color;
-}
-
-button[role="checkbox"] {
-  padding: 0;
-}
-
 @media (prefers-color-scheme: light) {
   :root {
     color: #213547;
@@ -69,9 +46,6 @@ button[role="checkbox"] {
   a:hover {
     color: #747bff;
   }
-  button {
-    background-color: #f9f9f9;
-  }
 }
 
 @layer base {

client/src/lib/configurationTypes.ts

@@ -0,0 +1,36 @@
+export type ConfigItem = {
+  label: string;
+  description: string;
+  value: string | number | boolean;
+};
+
+/**
+ * Configuration interface for the MCP Inspector, including settings for the MCP Client,
+ * Proxy Server, and Inspector UI/UX.
+ *
+ * Note: Configuration related to which MCP Server to use or any other MCP Server
+ * specific settings are outside the scope of this interface as of now.
+ */
+export type InspectorConfig = {
+  /**
+   * Maximum time in milliseconds to wait for a response from the MCP server before timing out.
+   */
+  MCP_SERVER_REQUEST_TIMEOUT: ConfigItem;
+
+  /**
+   * Whether to reset the timeout on progress notifications. Useful for long-running operations that send periodic progress updates.
+   * Refer: https://spec.modelcontextprotocol.io/specification/2025-03-26/basic/utilities/progress/#progress-flow
+   */
+  MCP_REQUEST_TIMEOUT_RESET_ON_PROGRESS: ConfigItem;
+
+  /**
+   * Maximum total time in milliseconds to wait for a response from the MCP server before timing out. Used in conjunction with MCP_SERVER_REQUEST_TIMEOUT_RESET_ON_PROGRESS.
+   * Refer: https://spec.modelcontextprotocol.io/specification/2025-03-26/basic/utilities/progress/#progress-flow
+   */
+  MCP_REQUEST_MAX_TOTAL_TIMEOUT: ConfigItem;
+
+  /**
+   * The full address of the MCP Proxy Server, in case it is running on a non-default address. Example: http://10.1.1.22:5577
+   */
+  MCP_PROXY_FULL_ADDRESS: ConfigItem;
+};

client/src/lib/constants.ts

@@ -1,3 +1,5 @@
+import { InspectorConfig } from "./configurationTypes";
+
 // OAuth-related session storage keys
 export const SESSION_KEYS = {
   CODE_VERIFIER: "mcp_code_verifier",
@@ -5,3 +7,40 @@ export const SESSION_KEYS = {
   TOKENS: "mcp_tokens",
   CLIENT_INFORMATION: "mcp_client_information",
 } as const;
+
+export type ConnectionStatus =
+  | "disconnected"
+  | "connected"
+  | "error"
+  | "error-connecting-to-proxy";
+
+export const DEFAULT_MCP_PROXY_LISTEN_PORT = "6277";
+
+/**
+ * Default configuration for the MCP Inspector, Currently persisted in local_storage in the Browser.
+ * Future plans: Provide json config file + Browser local_storage to override default values
+ **/
+export const DEFAULT_INSPECTOR_CONFIG: InspectorConfig = {
+  MCP_SERVER_REQUEST_TIMEOUT: {
+    label: "Request Timeout",
+    description: "Timeout for requests to the MCP server (ms)",
+    value: 10000,
+  },
+  MCP_REQUEST_TIMEOUT_RESET_ON_PROGRESS: {
+    label: "Reset Timeout on Progress",
+    description: "Reset timeout on progress notifications",
+    value: true,
+  },
+  MCP_REQUEST_MAX_TOTAL_TIMEOUT: {
+    label: "Maximum Total Timeout",
+    description:
+      "Maximum total timeout for requests sent to the MCP server (ms) (Use with progress notifications)",
+    value: 60000,
+  },
+  MCP_PROXY_FULL_ADDRESS: {
+    label: "Inspector Proxy Address",
+    description:
+      "Set this if you are running the MCP Inspector Proxy on a non-default address. Example: http://10.1.1.22:5577",
+    value: "",
+  },
+} as const;

client/src/lib/hooks/__tests__/useConnection.test.tsx

@@ -0,0 +1,164 @@
+import { renderHook, act } from "@testing-library/react";
+import { useConnection } from "../useConnection";
+import { z } from "zod";
+import { ClientRequest } from "@modelcontextprotocol/sdk/types.js";
+import { DEFAULT_INSPECTOR_CONFIG } from "../../constants";
+
+// Mock fetch
+global.fetch = jest.fn().mockResolvedValue({
+  json: () => Promise.resolve({ status: "ok" }),
+});
+
+// Mock the SDK dependencies
+const mockRequest = jest.fn().mockResolvedValue({ test: "response" });
+const mockClient = {
+  request: mockRequest,
+  notification: jest.fn(),
+  connect: jest.fn().mockResolvedValue(undefined),
+  close: jest.fn(),
+  getServerCapabilities: jest.fn(),
+  setNotificationHandler: jest.fn(),
+  setRequestHandler: jest.fn(),
+};
+
+jest.mock("@modelcontextprotocol/sdk/client/index.js", () => ({
+  Client: jest.fn().mockImplementation(() => mockClient),
+}));
+
+jest.mock("@modelcontextprotocol/sdk/client/sse.js", () => ({
+  SSEClientTransport: jest.fn(),
+  SseError: jest.fn(),
+}));
+
+jest.mock("@modelcontextprotocol/sdk/client/auth.js", () => ({
+  auth: jest.fn().mockResolvedValue("AUTHORIZED"),
+}));
+
+// Mock the toast hook
+jest.mock("@/hooks/use-toast", () => ({
+  useToast: () => ({
+    toast: jest.fn(),
+  }),
+}));
+
+// Mock the auth provider
+jest.mock("../../auth", () => ({
+  authProvider: {
+    tokens: jest.fn().mockResolvedValue({ access_token: "mock-token" }),
+  },
+}));
+
+describe("useConnection", () => {
+  const defaultProps = {
+    transportType: "sse" as const,
+    command: "",
+    args: "",
+    sseUrl: "http://localhost:8080",
+    env: {},
+    config: DEFAULT_INSPECTOR_CONFIG,
+  };
+
+  describe("Request Configuration", () => {
+    beforeEach(() => {
+      jest.clearAllMocks();
+    });
+
+    test("uses the default config values in makeRequest", async () => {
+      const { result } = renderHook(() => useConnection(defaultProps));
+
+      // Connect the client
+      await act(async () => {
+        await result.current.connect();
+      });
+
+      // Wait for state update
+      await act(async () => {
+        await new Promise((resolve) => setTimeout(resolve, 0));
+      });
+
+      const mockRequest: ClientRequest = {
+        method: "ping",
+        params: {},
+      };
+
+      const mockSchema = z.object({
+        test: z.string(),
+      });
+
+      await act(async () => {
+        await result.current.makeRequest(mockRequest, mockSchema);
+      });
+
+      expect(mockClient.request).toHaveBeenCalledWith(
+        mockRequest,
+        mockSchema,
+        expect.objectContaining({
+          timeout: DEFAULT_INSPECTOR_CONFIG.MCP_SERVER_REQUEST_TIMEOUT.value,
+          maxTotalTimeout:
+            DEFAULT_INSPECTOR_CONFIG.MCP_REQUEST_MAX_TOTAL_TIMEOUT.value,
+          resetTimeoutOnProgress:
+            DEFAULT_INSPECTOR_CONFIG.MCP_REQUEST_TIMEOUT_RESET_ON_PROGRESS
+              .value,
+        }),
+      );
+    });
+
+    test("overrides the default config values when passed in options in makeRequest", async () => {
+      const { result } = renderHook(() => useConnection(defaultProps));
+
+      // Connect the client
+      await act(async () => {
+        await result.current.connect();
+      });
+
+      // Wait for state update
+      await act(async () => {
+        await new Promise((resolve) => setTimeout(resolve, 0));
+      });
+
+      const mockRequest: ClientRequest = {
+        method: "ping",
+        params: {},
+      };
+
+      const mockSchema = z.object({
+        test: z.string(),
+      });
+
+      await act(async () => {
+        await result.current.makeRequest(mockRequest, mockSchema, {
+          timeout: 1000,
+          maxTotalTimeout: 2000,
+          resetTimeoutOnProgress: false,
+        });
+      });
+
+      expect(mockClient.request).toHaveBeenCalledWith(
+        mockRequest,
+        mockSchema,
+        expect.objectContaining({
+          timeout: 1000,
+          maxTotalTimeout: 2000,
+          resetTimeoutOnProgress: false,
+        }),
+      );
+    });
+  });
+
+  test("throws error when mcpClient is not connected", async () => {
+    const { result } = renderHook(() => useConnection(defaultProps));
+
+    const mockRequest: ClientRequest = {
+      method: "ping",
+      params: {},
+    };
+
+    const mockSchema = z.object({
+      test: z.string(),
+    });
+
+    await expect(
+      result.current.makeRequest(mockRequest, mockSchema),
+    ).rejects.toThrow("MCP client not connected");
+  });
+});

client/src/lib/hooks/useCompletionState.ts

@@ -1,4 +1,4 @@
-import { useState, useCallback, useEffect, useRef } from "react";
+import { useState, useCallback, useEffect, useRef, useMemo } from "react";
 import {
   ResourceReference,
   PromptReference,
@@ -15,9 +15,11 @@ function debounce<T extends (...args: any[]) => PromiseLike<void>>(
   wait: number,
 ): (...args: Parameters<T>) => void {
   let timeout: ReturnType<typeof setTimeout>;
-  return function (...args: Parameters<T>) {
+  return (...args: Parameters<T>) => {
     clearTimeout(timeout);
-    timeout = setTimeout(() => func(...args), wait);
+    timeout = setTimeout(() => {
+      void func(...args);
+    }, wait);
   };
 }
 
@@ -58,8 +60,8 @@ export function useCompletionState(
     });
   }, [cleanup]);
 
-  const requestCompletions = useCallback(
-    debounce(
+  const requestCompletions = useMemo(() => {
+    return debounce(
       async (
         ref: ResourceReference | PromptReference,
         argName: string,
@@ -94,7 +96,7 @@ export function useCompletionState(
               loading: { ...prev.loading, [argName]: false },
             }));
           }
-        } catch (err) {
+        } catch {
           if (!abortController.signal.aborted) {
             setState((prev) => ({
               ...prev,
@@ -108,9 +110,8 @@ export function useCompletionState(
         }
       },
       debounceMs,
-    ),
-    [handleCompletion, completionsSupported, cleanup, debounceMs],
     );
+  }, [handleCompletion, completionsSupported, cleanup, debounceMs]);
 
   // Clear completions when support status changes
   useEffect(() => {

client/src/lib/hooks/useConnection.ts

@@ -8,7 +8,6 @@ import {
   ClientRequest,
   CreateMessageRequestSchema,
   ListRootsRequestSchema,
-  ProgressNotificationSchema,
   ResourceUpdatedNotificationSchema,
   LoggingMessageNotificationSchema,
   Request,
@@ -19,19 +18,28 @@ import {
   McpError,
   CompleteResultSchema,
   ErrorCode,
+  CancelledNotificationSchema,
+  ResourceListChangedNotificationSchema,
+  ToolListChangedNotificationSchema,
+  PromptListChangedNotificationSchema,
+  Progress,
 } from "@modelcontextprotocol/sdk/types.js";
+import { RequestOptions } from "@modelcontextprotocol/sdk/shared/protocol.js";
 import { useState } from "react";
-import { toast } from "react-toastify";
+import { useToast } from "@/hooks/use-toast";
 import { z } from "zod";
-import { SESSION_KEYS } from "../constants";
+import { ConnectionStatus, SESSION_KEYS } from "../constants";
 import { Notification, StdErrNotificationSchema } from "../notificationTypes";
 import { auth } from "@modelcontextprotocol/sdk/client/auth.js";
 import { authProvider } from "../auth";
 import packageJson from "../../../package.json";
-
-const params = new URLSearchParams(window.location.search);
-const DEFAULT_REQUEST_TIMEOUT_MSEC =
-  parseInt(params.get("timeout") ?? "") || 10000;
+import {
+  getMCPProxyAddress,
+  getMCPServerRequestMaxTotalTimeout,
+  resetRequestTimeoutOnProgress,
+} from "@/utils/configUtils";
+import { getMCPServerRequestTimeout } from "@/utils/configUtils";
+import { InspectorConfig } from "../configurationTypes";
 
 interface UseConnectionOptions {
   transportType: "stdio" | "sse";
@@ -39,38 +47,32 @@ interface UseConnectionOptions {
   args: string;
   sseUrl: string;
   env: Record<string, string>;
-  proxyServerUrl: string;
   bearerToken?: string;
-  requestTimeout?: number;
+  config: InspectorConfig;
   onNotification?: (notification: Notification) => void;
   onStdErrNotification?: (notification: Notification) => void;
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   onPendingRequest?: (request: any, resolve: any, reject: any) => void;
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   getRoots?: () => any[];
 }
 
-interface RequestOptions {
-  signal?: AbortSignal;
-  timeout?: number;
-  suppressToast?: boolean;
-}
-
 export function useConnection({
   transportType,
   command,
   args,
   sseUrl,
   env,
-  proxyServerUrl,
   bearerToken,
-  requestTimeout = DEFAULT_REQUEST_TIMEOUT_MSEC,
+  config,
   onNotification,
   onStdErrNotification,
   onPendingRequest,
   getRoots,
 }: UseConnectionOptions) {
-  const [connectionStatus, setConnectionStatus] = useState<
-    "disconnected" | "connected" | "error"
-  >("disconnected");
+  const [connectionStatus, setConnectionStatus] =
+    useState<ConnectionStatus>("disconnected");
+  const { toast } = useToast();
   const [serverCapabilities, setServerCapabilities] =
     useState<ServerCapabilities | null>(null);
   const [mcpClient, setMcpClient] = useState<Client | null>(null);
@@ -92,38 +94,61 @@ export function useConnection({
   const makeRequest = async <T extends z.ZodType>(
     request: ClientRequest,
     schema: T,
-    options?: RequestOptions,
+    options?: RequestOptions & { suppressToast?: boolean },
   ): Promise<z.output<T>> => {
     if (!mcpClient) {
       throw new Error("MCP client not connected");
     }
-
     try {
       const abortController = new AbortController();
-      const timeoutId = setTimeout(() => {
-        abortController.abort("Request timed out");
-      }, options?.timeout ?? requestTimeout);
+
+      // prepare MCP Client request options
+      const mcpRequestOptions: RequestOptions = {
+        signal: options?.signal ?? abortController.signal,
+        resetTimeoutOnProgress:
+          options?.resetTimeoutOnProgress ??
+          resetRequestTimeoutOnProgress(config),
+        timeout: options?.timeout ?? getMCPServerRequestTimeout(config),
+        maxTotalTimeout:
+          options?.maxTotalTimeout ??
+          getMCPServerRequestMaxTotalTimeout(config),
+      };
+
+      // If progress notifications are enabled, add an onprogress hook to the MCP Client request options
+      // This is required by SDK to reset the timeout on progress notifications
+      if (mcpRequestOptions.resetTimeoutOnProgress) {
+        mcpRequestOptions.onprogress = (params: Progress) => {
+          // Add progress notification to `Server Notification` window in the UI
+          if (onNotification) {
+            onNotification({
+              method: "notification/progress",
+              params,
+            });
+          }
+        };
+      }
 
       let response;
       try {
-        response = await mcpClient.request(request, schema, {
-          signal: options?.signal ?? abortController.signal,
-        });
+        response = await mcpClient.request(request, schema, mcpRequestOptions);
+
         pushHistory(request, response);
       } catch (error) {
         const errorMessage =
           error instanceof Error ? error.message : String(error);
         pushHistory(request, { error: errorMessage });
         throw error;
-      } finally {
-        clearTimeout(timeoutId);
       }
 
       return response;
     } catch (e: unknown) {
       if (!options?.suppressToast) {
         const errorString = (e as Error).message ?? String(e);
-        toast.error(errorString);
+        toast({
+          title: "Error",
+          description: errorString,
+          variant: "destructive",
+        });
       }
       throw e;
     }
@@ -165,7 +190,11 @@ export function useConnection({
       }
 
       // Unexpected errors - show toast and rethrow
-      toast.error(e instanceof Error ? e.message : String(e));
+      toast({
+        title: "Error",
+        description: e instanceof Error ? e.message : String(e),
+        variant: "destructive",
+      });
       throw e;
     }
   };
@@ -173,7 +202,11 @@ export function useConnection({
   const sendNotification = async (notification: ClientNotification) => {
     if (!mcpClient) {
       const error = new Error("MCP client not connected");
-      toast.error(error.message);
+      toast({
+        title: "Error",
+        description: error.message,
+        variant: "destructive",
+      });
       throw error;
     }
 
@@ -186,7 +219,25 @@ export function useConnection({
         // Log MCP protocol errors
         pushHistory(notification, { error: e.message });
       }
-      toast.error(e instanceof Error ? e.message : String(e));
+      toast({
+        title: "Error",
+        description: e instanceof Error ? e.message : String(e),
+        variant: "destructive",
+      });
+      throw e;
+    }
+  };
+
+  const checkProxyHealth = async () => {
+    try {
+      const proxyHealthUrl = new URL(`${getMCPProxyAddress(config)}/health`);
+      const proxyHealthResponse = await fetch(proxyHealthUrl);
+      const proxyHealth = await proxyHealthResponse.json();
+      if (proxyHealth?.status !== "ok") {
+        throw new Error("MCP Proxy Server is not healthy");
+      }
+    } catch (e) {
+      console.error("Couldn't connect to MCP Proxy Server", e);
       throw e;
     }
   };
@@ -203,7 +254,6 @@ export function useConnection({
   };
 
   const connect = async (_e?: unknown, retryCount: number = 0) => {
-    try {
     const client = new Client<Request, Notification, Result>(
       {
         name: "mcp-inspector",
@@ -219,17 +269,23 @@ export function useConnection({
       },
     );
 
-      const backendUrl = new URL(`${proxyServerUrl}/sse`);
-
-      backendUrl.searchParams.append("transportType", transportType);
+    try {
+      await checkProxyHealth();
+    } catch {
+      setConnectionStatus("error-connecting-to-proxy");
+      return;
+    }
+    const mcpProxyServerUrl = new URL(`${getMCPProxyAddress(config)}/sse`);
+    mcpProxyServerUrl.searchParams.append("transportType", transportType);
     if (transportType === "stdio") {
-        backendUrl.searchParams.append("command", command);
-        backendUrl.searchParams.append("args", args);
-        backendUrl.searchParams.append("env", JSON.stringify(env));
+      mcpProxyServerUrl.searchParams.append("command", command);
+      mcpProxyServerUrl.searchParams.append("args", args);
+      mcpProxyServerUrl.searchParams.append("env", JSON.stringify(env));
     } else {
-        backendUrl.searchParams.append("url", sseUrl);
+      mcpProxyServerUrl.searchParams.append("url", sseUrl);
     }
 
+    try {
       // Inject auth manually instead of using SSEClientTransport, because we're
       // proxying through the inspector server first.
       const headers: HeadersInit = {};
@@ -240,7 +296,7 @@ export function useConnection({
         headers["Authorization"] = `Bearer ${token}`;
       }
 
-      const clientTransport = new SSEClientTransport(backendUrl, {
+      const clientTransport = new SSEClientTransport(mcpProxyServerUrl, {
         eventSourceInit: {
           fetch: (url, init) => fetch(url, { ...init, headers }),
         },
@@ -250,20 +306,23 @@ export function useConnection({
       });
 
       if (onNotification) {
-        client.setNotificationHandler(
-          ProgressNotificationSchema,
-          onNotification,
-        );
-
-        client.setNotificationHandler(
-          ResourceUpdatedNotificationSchema,
-          onNotification,
-        );
-
-        client.setNotificationHandler(
+        [
+          CancelledNotificationSchema,
           LoggingMessageNotificationSchema,
-          onNotification,
-        );
+          ResourceUpdatedNotificationSchema,
+          ResourceListChangedNotificationSchema,
+          ToolListChangedNotificationSchema,
+          PromptListChangedNotificationSchema,
+        ].forEach((notificationSchema) => {
+          client.setNotificationHandler(notificationSchema, onNotification);
+        });
+
+        client.fallbackNotificationHandler = (
+          notification: Notification,
+        ): Promise<void> => {
+          onNotification(notification);
+          return Promise.resolve();
+        };
       }
 
       if (onStdErrNotification) {
@@ -276,7 +335,10 @@ export function useConnection({
       try {
         await client.connect(clientTransport);
       } catch (error) {
-        console.error("Failed to connect to MCP server:", error);
+        console.error(
+          `Failed to connect to MCP Server via the MCP Inspector Proxy: ${mcpProxyServerUrl}:`,
+          error,
+        );
         const shouldRetry = await handleAuthError(error);
         if (shouldRetry) {
           return connect(undefined, retryCount + 1);
@@ -315,6 +377,14 @@ export function useConnection({
     }
   };
 
+  const disconnect = async () => {
+    await mcpClient?.close();
+    setMcpClient(null);
+    setConnectionStatus("disconnected");
+    setCompletionsSupported(false);
+    setServerCapabilities(null);
+  };
+
   return {
     connectionStatus,
     serverCapabilities,
@@ -325,5 +395,6 @@ export function useConnection({
     handleCompletion,
     completionsSupported,
     connect,
+    disconnect,
   };
 }

client/src/lib/notificationTypes.ts

@@ -14,7 +14,9 @@ export const StdErrNotificationSchema = BaseNotificationSchema.extend({
 
 export const NotificationSchema = ClientNotificationSchema.or(
   StdErrNotificationSchema,
-).or(ServerNotificationSchema);
+)
+  .or(ServerNotificationSchema)
+  .or(BaseNotificationSchema);
 
 export type StdErrNotification = z.infer<typeof StdErrNotificationSchema>;
 export type Notification = z.infer<typeof NotificationSchema>;

client/src/lib/useTheme.ts

@@ -1,4 +1,4 @@
-import { useCallback, useEffect, useState } from "react";
+import { useCallback, useEffect, useMemo, useState } from "react";
 
 type Theme = "light" | "dark" | "system";
 
@@ -36,16 +36,17 @@ const useTheme = (): [Theme, (mode: Theme) => void] => {
     };
   }, [theme]);
 
-  return [
-    theme,
-    useCallback((newTheme: Theme) => {
+  const setThemeWithSideEffect = useCallback((newTheme: Theme) => {
     setTheme(newTheme);
     localStorage.setItem("theme", newTheme);
     if (newTheme !== "system") {
       document.documentElement.classList.toggle("dark", newTheme === "dark");
     }
-    }, []),
-  ];
+  }, []);
+  return useMemo(
+    () => [theme, setThemeWithSideEffect],
+    [theme, setThemeWithSideEffect],
+  );
 };
 
 export default useTheme;

client/src/main.tsx

@@ -1,13 +1,15 @@
 import { StrictMode } from "react";
 import { createRoot } from "react-dom/client";
-import { ToastContainer } from "react-toastify";
-import "react-toastify/dist/ReactToastify.css";
+import { Toaster } from "@/components/ui/toaster.tsx";
 import App from "./App.tsx";
 import "./index.css";
+import { TooltipProvider } from "./components/ui/tooltip.tsx";
 
 createRoot(document.getElementById("root")!).render(
   <StrictMode>
+    <TooltipProvider>
       <App />
-    <ToastContainer />
+    </TooltipProvider>
+    <Toaster />
   </StrictMode>,
 );

client/src/utils/__tests__/jsonUtils.test.ts

@@ -1,5 +1,146 @@
-import { updateValueAtPath, getValueAtPath } from "../jsonPathUtils";
-import { JsonValue } from "../../components/DynamicJsonForm";
+import {
+  getDataType,
+  tryParseJson,
+  updateValueAtPath,
+  getValueAtPath,
+} from "../jsonUtils";
+import type { JsonValue } from "../jsonUtils";
+
+describe("getDataType", () => {
+  test("should return 'string' for string values", () => {
+    expect(getDataType("hello")).toBe("string");
+    expect(getDataType("")).toBe("string");
+  });
+
+  test("should return 'number' for number values", () => {
+    expect(getDataType(123)).toBe("number");
+    expect(getDataType(0)).toBe("number");
+    expect(getDataType(-10)).toBe("number");
+    expect(getDataType(1.5)).toBe("number");
+    expect(getDataType(NaN)).toBe("number");
+    expect(getDataType(Infinity)).toBe("number");
+  });
+
+  test("should return 'boolean' for boolean values", () => {
+    expect(getDataType(true)).toBe("boolean");
+    expect(getDataType(false)).toBe("boolean");
+  });
+
+  test("should return 'undefined' for undefined value", () => {
+    expect(getDataType(undefined)).toBe("undefined");
+  });
+
+  test("should return 'object' for object values", () => {
+    expect(getDataType({})).toBe("object");
+    expect(getDataType({ key: "value" })).toBe("object");
+  });
+
+  test("should return 'array' for array values", () => {
+    expect(getDataType([])).toBe("array");
+    expect(getDataType([1, 2, 3])).toBe("array");
+    expect(getDataType(["a", "b", "c"])).toBe("array");
+    expect(getDataType([{}, { nested: true }])).toBe("array");
+  });
+
+  test("should return 'null' for null value", () => {
+    expect(getDataType(null)).toBe("null");
+  });
+});
+
+describe("tryParseJson", () => {
+  test("should correctly parse valid JSON object", () => {
+    const jsonString = '{"name":"test","value":123}';
+    const result = tryParseJson(jsonString);
+
+    expect(result.success).toBe(true);
+    expect(result.data).toEqual({ name: "test", value: 123 });
+  });
+
+  test("should correctly parse valid JSON array", () => {
+    const jsonString = '[1,2,3,"test"]';
+    const result = tryParseJson(jsonString);
+
+    expect(result.success).toBe(true);
+    expect(result.data).toEqual([1, 2, 3, "test"]);
+  });
+
+  test("should correctly parse JSON with whitespace", () => {
+    const jsonString = '  {  "name"  :  "test"  }  ';
+    const result = tryParseJson(jsonString);
+
+    expect(result.success).toBe(true);
+    expect(result.data).toEqual({ name: "test" });
+  });
+
+  test("should correctly parse nested JSON structures", () => {
+    const jsonString =
+      '{"user":{"name":"test","details":{"age":30}},"items":[1,2,3]}';
+    const result = tryParseJson(jsonString);
+
+    expect(result.success).toBe(true);
+    expect(result.data).toEqual({
+      user: {
+        name: "test",
+        details: {
+          age: 30,
+        },
+      },
+      items: [1, 2, 3],
+    });
+  });
+
+  test("should correctly parse empty objects and arrays", () => {
+    expect(tryParseJson("{}").success).toBe(true);
+    expect(tryParseJson("{}").data).toEqual({});
+
+    expect(tryParseJson("[]").success).toBe(true);
+    expect(tryParseJson("[]").data).toEqual([]);
+  });
+
+  test("should return failure for non-JSON strings", () => {
+    const nonJsonString = "this is not json";
+    const result = tryParseJson(nonJsonString);
+
+    expect(result.success).toBe(false);
+    expect(result.data).toBe(nonJsonString);
+  });
+
+  test("should return failure for malformed JSON", () => {
+    const malformedJson = '{"name":"test",}';
+    const result = tryParseJson(malformedJson);
+
+    expect(result.success).toBe(false);
+    expect(result.data).toBe(malformedJson);
+  });
+
+  test("should return failure for strings with correct delimiters but invalid JSON", () => {
+    const invalidJson = "{name:test}";
+    const result = tryParseJson(invalidJson);
+
+    expect(result.success).toBe(false);
+    expect(result.data).toBe(invalidJson);
+  });
+
+  test("should handle edge cases", () => {
+    expect(tryParseJson("").success).toBe(false);
+    expect(tryParseJson("").data).toBe("");
+
+    expect(tryParseJson("   ").success).toBe(false);
+    expect(tryParseJson("   ").data).toBe("   ");
+
+    expect(tryParseJson("null").success).toBe(false);
+    expect(tryParseJson("null").data).toBe("null");
+
+    expect(tryParseJson('"string"').success).toBe(false);
+    expect(tryParseJson('"string"').data).toBe('"string"');
+
+    expect(tryParseJson("123").success).toBe(false);
+    expect(tryParseJson("123").data).toBe("123");
+
+    expect(tryParseJson("true").success).toBe(false);
+    expect(tryParseJson("true").data).toBe("true");
+  });
+});
 
 describe("updateValueAtPath", () => {
   // Basic functionality tests
@@ -8,17 +149,17 @@ describe("updateValueAtPath", () => {
   });
 
   test("initializes an empty object when input is null/undefined and path starts with a string", () => {
-    expect(updateValueAtPath(null as any, ["foo"], "bar")).toEqual({
+    expect(updateValueAtPath(null, ["foo"], "bar")).toEqual({
       foo: "bar",
     });
-    expect(updateValueAtPath(undefined as any, ["foo"], "bar")).toEqual({
+    expect(updateValueAtPath(undefined, ["foo"], "bar")).toEqual({
       foo: "bar",
     });
   });
 
   test("initializes an empty array when input is null/undefined and path starts with a number", () => {
-    expect(updateValueAtPath(null as any, ["0"], "bar")).toEqual(["bar"]);
-    expect(updateValueAtPath(undefined as any, ["0"], "bar")).toEqual(["bar"]);
+    expect(updateValueAtPath(null, ["0"], "bar")).toEqual(["bar"]);
+    expect(updateValueAtPath(undefined, ["0"], "bar")).toEqual(["bar"]);
   });
 
   // Object update tests
@@ -152,10 +293,8 @@ describe("getValueAtPath", () => {
   });
 
   test("returns default value when input is null/undefined", () => {
-    expect(getValueAtPath(null as any, ["foo"], "default")).toBe("default");
-    expect(getValueAtPath(undefined as any, ["foo"], "default")).toBe(
-      "default",
-    );
+    expect(getValueAtPath(null, ["foo"], "default")).toBe("default");
+    expect(getValueAtPath(undefined, ["foo"], "default")).toBe("default");
   });
 
   test("handles array indices correctly", () => {

client/src/utils/__tests__/schemaUtils.test.ts

@@ -1,5 +1,5 @@
 import { generateDefaultValue, formatFieldLabel } from "../schemaUtils";
-import { JsonSchemaType } from "../../components/DynamicJsonForm";
+import type { JsonSchemaType } from "../jsonUtils";
 
 describe("generateDefaultValue", () => {
   test("generates default string", () => {

client/src/utils/configUtils.ts

@@ -0,0 +1,26 @@
+import { InspectorConfig } from "@/lib/configurationTypes";
+import { DEFAULT_MCP_PROXY_LISTEN_PORT } from "@/lib/constants";
+
+export const getMCPProxyAddress = (config: InspectorConfig): string => {
+  const proxyFullAddress = config.MCP_PROXY_FULL_ADDRESS.value as string;
+  if (proxyFullAddress) {
+    return proxyFullAddress;
+  }
+  return `${window.location.protocol}//${window.location.hostname}:${DEFAULT_MCP_PROXY_LISTEN_PORT}`;
+};
+
+export const getMCPServerRequestTimeout = (config: InspectorConfig): number => {
+  return config.MCP_SERVER_REQUEST_TIMEOUT.value as number;
+};
+
+export const resetRequestTimeoutOnProgress = (
+  config: InspectorConfig,
+): boolean => {
+  return config.MCP_REQUEST_TIMEOUT_RESET_ON_PROGRESS.value as boolean;
+};
+
+export const getMCPServerRequestMaxTotalTimeout = (
+  config: InspectorConfig,
+): number => {
+  return config.MCP_REQUEST_MAX_TOTAL_TIMEOUT.value as number;
+};

client/src/utils/jsonUtils.ts

@@ -1,7 +1,66 @@
-import { JsonValue } from "../components/DynamicJsonForm";
+export type JsonValue =
+  | string
+  | number
+  | boolean
+  | null
+  | undefined
+  | JsonValue[]
+  | { [key: string]: JsonValue };
+
+export type JsonSchemaType = {
+  type:
+    | "string"
+    | "number"
+    | "integer"
+    | "boolean"
+    | "array"
+    | "object"
+    | "null";
+  description?: string;
+  required?: boolean;
+  default?: JsonValue;
+  properties?: Record<string, JsonSchemaType>;
+  items?: JsonSchemaType;
+};
 
 export type JsonObject = { [key: string]: JsonValue };
 
+export type DataType =
+  | "string"
+  | "number"
+  | "bigint"
+  | "boolean"
+  | "symbol"
+  | "undefined"
+  | "object"
+  | "function"
+  | "array"
+  | "null";
+
+export function getDataType(value: JsonValue): DataType {
+  if (Array.isArray(value)) return "array";
+  if (value === null) return "null";
+  return typeof value;
+}
+
+export function tryParseJson(str: string): {
+  success: boolean;
+  data: JsonValue;
+} {
+  const trimmed = str.trim();
+  if (
+    !(trimmed.startsWith("{") && trimmed.endsWith("}")) &&
+    !(trimmed.startsWith("[") && trimmed.endsWith("]"))
+  ) {
+    return { success: false, data: str };
+  }
+  try {
+    return { success: true, data: JSON.parse(str) };
+  } catch {
+    return { success: false, data: str };
+  }
+}
+
 /**
  * Updates a value at a specific path in a nested JSON structure
  * @param obj The original JSON value

client/src/utils/schemaUtils.ts

@@ -1,5 +1,4 @@
-import { JsonValue, JsonSchemaType } from "../components/DynamicJsonForm";
-import { JsonObject } from "./jsonPathUtils";
+import type { JsonValue, JsonSchemaType, JsonObject } from "./jsonUtils";
 
 /**
  * Generates a default value based on a JSON schema type

client/tsconfig.app.json

@@ -24,7 +24,8 @@
     "noUnusedLocals": true,
     "noUnusedParameters": true,
     "noFallthroughCasesInSwitch": true,
-    "resolveJsonModule": true
+    "resolveJsonModule": true,
+    "types": ["jest", "@testing-library/jest-dom", "node"]
   },
   "include": ["src"]
 }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@modelcontextprotocol/inspector",
-  "version": "0.7.0",
+  "version": "0.9.0",
   "description": "Model Context Protocol inspector",
   "license": "MIT",
   "author": "Anthropic, PBC (https://anthropic.com)",
@@ -23,6 +23,7 @@
   "scripts": {
     "dev": "concurrently \"cd client && npm run dev\" \"cd server && npm run dev\"",
     "dev:windows": "concurrently \"cd client && npm run dev\" \"cd server && npm run dev:windows",
+    "test": "npm run prettier-check && cd client && npm test",
     "build-server": "cd server && npm run build",
     "build-client": "cd client && npm run build",
     "build": "npm run build-server && npm run build-client",
@@ -31,11 +32,12 @@
     "start": "node ./bin/cli.js",
     "prepare": "npm run build",
     "prettier-fix": "prettier --write .",
+    "prettier-check": "prettier --check .",
     "publish-all": "npm publish --workspaces --access public && npm publish --access public"
   },
   "dependencies": {
-    "@modelcontextprotocol/inspector-client": "^0.7.0",
-    "@modelcontextprotocol/inspector-server": "^0.7.0",
+    "@modelcontextprotocol/inspector-client": "^0.9.0",
+    "@modelcontextprotocol/inspector-server": "^0.9.0",
     "concurrently": "^9.0.1",
     "shell-quote": "^1.8.2",
     "spawn-rx": "^5.1.2",

server/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@modelcontextprotocol/inspector-server",
-  "version": "0.7.0",
+  "version": "0.9.0",
   "description": "Server-side application for the Model Context Protocol inspector",
   "license": "MIT",
   "author": "Anthropic, PBC (https://anthropic.com)",
@@ -27,7 +27,7 @@
     "typescript": "^5.6.2"
   },
   "dependencies": {
-    "@modelcontextprotocol/sdk": "^1.6.1",
+    "@modelcontextprotocol/sdk": "^1.9.0",
     "cors": "^2.8.5",
     "express": "^4.21.0",
     "ws": "^8.18.0",

server/src/index.ts

@@ -12,6 +12,7 @@ import {
   StdioClientTransport,
   getDefaultEnvironment,
 } from "@modelcontextprotocol/sdk/client/stdio.js";
+import { Transport } from "@modelcontextprotocol/sdk/shared/transport.js";
 import { SSEServerTransport } from "@modelcontextprotocol/sdk/server/sse.js";
 import express from "express";
 import { findActualExecutable } from "spawn-rx";
@@ -37,7 +38,7 @@ app.use(cors());
 
 let webAppTransports: SSEServerTransport[] = [];
 
-const createTransport = async (req: express.Request) => {
+const createTransport = async (req: express.Request): Promise<Transport> => {
   const query = req.query;
   console.log("Query parameters:", query);
 
@@ -69,6 +70,7 @@ const createTransport = async (req: express.Request) => {
     const headers: HeadersInit = {
       Accept: "text/event-stream",
     };
+
     for (const key of SSE_HEADERS_PASSTHROUGH) {
       if (req.headers[key] === undefined) {
         continue;
@@ -98,12 +100,14 @@ const createTransport = async (req: express.Request) => {
   }
 };
 
+let backingServerTransport: Transport | undefined;
+
 app.get("/sse", async (req, res) => {
   try {
     console.log("New SSE connection");
 
-    let backingServerTransport;
     try {
+      await backingServerTransport?.close();
       backingServerTransport = await createTransport(req);
     } catch (error) {
       if (error instanceof SseError && error.code === 401) {
@@ -169,6 +173,12 @@ app.post("/message", async (req, res) => {
   }
 });
 
+app.get("/health", (req, res) => {
+  res.json({
+    status: "ok",
+  });
+});
+
 app.get("/config", (req, res) => {
   try {
     res.json({
@@ -182,17 +192,17 @@ app.get("/config", (req, res) => {
   }
 });
 
-const PORT = process.env.PORT || 3000;
+const PORT = process.env.PORT || 6277;
 
-try {
-  const server = app.listen(PORT);
-
-  server.on("listening", () => {
-    const addr = server.address();
-    const port = typeof addr === "string" ? addr : addr?.port;
-    console.log(`Proxy server listening on port ${port}`);
-  });
-} catch (error) {
-  console.error("Failed to start server:", error);
+const server = app.listen(PORT);
+server.on("listening", () => {
+  console.log(`⚙️ Proxy server listening on port ${PORT}`);
+});
+server.on("error", (err) => {
+  if (err.message.includes(`EADDRINUSE`)) {
+    console.error(`❌  Proxy Server PORT IS IN USE at port ${PORT} ❌ `);
+  } else {
+    console.error(err.message);
+  }
   process.exit(1);
-}
+});