Fix: Store auth tokens with server-specific keys

client/src/components/OAuthCallback.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useRef } from "react";
-import { authProvider } from "../lib/auth";
+import { InspectorOAuthClientProvider } from "../lib/auth";
 import { SESSION_KEYS } from "../lib/constants";
 import { auth } from "@modelcontextprotocol/sdk/client/auth.js";
 
@@ -25,7 +25,10 @@ const OAuthCallback = () => {
       }
 
       try {
-        const result = await auth(authProvider, {
+        // Create an auth provider with the current server URL
+        const serverAuthProvider = new InspectorOAuthClientProvider(serverUrl);
+
+        const result = await auth(serverAuthProvider, {
           serverUrl,
           authorizationCode: code,
         });

client/src/lib/auth.ts

@@ -5,9 +5,14 @@ import {
   OAuthTokens,
   OAuthTokensSchema,
 } from "@modelcontextprotocol/sdk/shared/auth.js";
-import { SESSION_KEYS } from "./constants";
+import { SESSION_KEYS, getServerSpecificKey } from "./constants";
+
+export class InspectorOAuthClientProvider implements OAuthClientProvider {
+  constructor(private serverUrl: string) {
+    // Save the server URL to session storage
+    sessionStorage.setItem(SESSION_KEYS.SERVER_URL, serverUrl);
+  }
 
-class InspectorOAuthClientProvider implements OAuthClientProvider {
   get redirectUrl() {
     return window.location.origin + "/oauth/callback";
   }
@@ -24,7 +29,11 @@ class InspectorOAuthClientProvider implements OAuthClientProvider {
   }
 
   async clientInformation() {
-    const value = sessionStorage.getItem(SESSION_KEYS.CLIENT_INFORMATION);
+    const key = getServerSpecificKey(
+      SESSION_KEYS.CLIENT_INFORMATION,
+      this.serverUrl,
+    );
+    const value = sessionStorage.getItem(key);
     if (!value) {
       return undefined;
     }
@@ -33,14 +42,16 @@ class InspectorOAuthClientProvider implements OAuthClientProvider {
   }
 
   saveClientInformation(clientInformation: OAuthClientInformation) {
-    sessionStorage.setItem(
+    const key = getServerSpecificKey(
       SESSION_KEYS.CLIENT_INFORMATION,
-      JSON.stringify(clientInformation),
+      this.serverUrl,
     );
+    sessionStorage.setItem(key, JSON.stringify(clientInformation));
   }
 
   async tokens() {
-    const tokens = sessionStorage.getItem(SESSION_KEYS.TOKENS);
+    const key = getServerSpecificKey(SESSION_KEYS.TOKENS, this.serverUrl);
+    const tokens = sessionStorage.getItem(key);
     if (!tokens) {
       return undefined;
     }
@@ -49,25 +60,32 @@ class InspectorOAuthClientProvider implements OAuthClientProvider {
   }
 
   saveTokens(tokens: OAuthTokens) {
-    sessionStorage.setItem(SESSION_KEYS.TOKENS, JSON.stringify(tokens));
+    const key = getServerSpecificKey(SESSION_KEYS.TOKENS, this.serverUrl);
+    sessionStorage.setItem(key, JSON.stringify(tokens));
   }
 
   redirectToAuthorization(authorizationUrl: URL) {
     window.location.href = authorizationUrl.href;
   }
 
   saveCodeVerifier(codeVerifier: string) {
-    sessionStorage.setItem(SESSION_KEYS.CODE_VERIFIER, codeVerifier);
+    const key = getServerSpecificKey(
+      SESSION_KEYS.CODE_VERIFIER,
+      this.serverUrl,
+    );
+    sessionStorage.setItem(key, codeVerifier);
   }
 
   codeVerifier() {
-    const verifier = sessionStorage.getItem(SESSION_KEYS.CODE_VERIFIER);
+    const key = getServerSpecificKey(
+      SESSION_KEYS.CODE_VERIFIER,
+      this.serverUrl,
+    );
+    const verifier = sessionStorage.getItem(key);
     if (!verifier) {
       throw new Error("No code verifier saved for session");
     }
 
     return verifier;
   }
 }
-
-export const authProvider = new InspectorOAuthClientProvider();

client/src/lib/constants.ts

@@ -8,6 +8,15 @@ export const SESSION_KEYS = {
   CLIENT_INFORMATION: "mcp_client_information",
 } as const;
 
+// Generate server-specific session storage keys
+export const getServerSpecificKey = (
+  baseKey: string,
+  serverUrl?: string,
+): string => {
+  if (!serverUrl) return baseKey;
+  return `[${serverUrl}] ${baseKey}`;
+};
+
 export type ConnectionStatus =
   | "disconnected"
   | "connected"

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

@@ -45,9 +45,9 @@ jest.mock("@/hooks/use-toast", () => ({
 
 // Mock the auth provider
 jest.mock("../../auth", () => ({
-  authProvider: {
+  InspectorOAuthClientProvider: jest.fn().mockImplementation(() => ({
     tokens: jest.fn().mockResolvedValue({ access_token: "mock-token" }),
-  },
+  })),
 }));
 
 describe("useConnection", () => {

client/src/lib/hooks/useConnection.ts

@@ -28,10 +28,10 @@ import { RequestOptions } from "@modelcontextprotocol/sdk/shared/protocol.js";
 import { useState } from "react";
 import { useToast } from "@/hooks/use-toast";
 import { z } from "zod";
-import { ConnectionStatus, SESSION_KEYS } from "../constants";
+import { ConnectionStatus } from "../constants";
 import { Notification, StdErrNotificationSchema } from "../notificationTypes";
 import { auth } from "@modelcontextprotocol/sdk/client/auth.js";
-import { authProvider } from "../auth";
+import { InspectorOAuthClientProvider } from "../auth";
 import packageJson from "../../../package.json";
 import {
   getMCPProxyAddress,
@@ -246,9 +246,10 @@ export function useConnection({
 
   const handleAuthError = async (error: unknown) => {
     if (error instanceof SseError && error.code === 401) {
-      sessionStorage.setItem(SESSION_KEYS.SERVER_URL, sseUrl);
+      // Create a new auth provider with the current server URL
+      const serverAuthProvider = new InspectorOAuthClientProvider(sseUrl);
 
-      const result = await auth(authProvider, { serverUrl: sseUrl });
+      const result = await auth(serverAuthProvider, { serverUrl: sseUrl });
       return result === "AUTHORIZED";
     }
 
@@ -292,8 +293,12 @@ export function useConnection({
       // proxying through the inspector server first.
       const headers: HeadersInit = {};
 
+      // Create an auth provider with the current server URL
+      const serverAuthProvider = new InspectorOAuthClientProvider(sseUrl);
+
       // Use manually provided bearer token if available, otherwise use OAuth tokens
-      const token = bearerToken || (await authProvider.tokens())?.access_token;
+      const token =
+        bearerToken || (await serverAuthProvider.tokens())?.access_token;
       if (token) {
         const authHeaderName = headerName || "Authorization";
         headers[authHeaderName] = `Bearer ${token}`;