Add verify_session tool to MCP server

mcp-server.js

@@ -53,6 +53,20 @@ class ReubenOSMCPServer {
             },
           },
         },
+        {
+          name: 'verify_session',
+          description: 'Verify if a session key is valid and active',
+          inputSchema: {
+            type: 'object',
+            properties: {
+              sessionKey: {
+                type: 'string',
+                description: 'Session key to verify',
+              },
+            },
+            required: ['sessionKey'],
+          },
+        },
         {
           name: 'upload_file',
           description: 'Upload a file to session or public folder',
@@ -282,6 +296,8 @@ class ReubenOSMCPServer {
         switch (name) {
           case 'create_session':
             return await this.createSession(args);
+          case 'verify_session':
+            return await this.verifySession(args);
           case 'upload_file':
             return await this.uploadFile(args);
           case 'download_file':
@@ -338,6 +354,36 @@ class ReubenOSMCPServer {
     };
   }
 
+  async verifySession(args) {
+    const response = await fetch(`${BASE_URL}/api/sessions/verify`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ sessionKey: args.sessionKey }),
+    });
+
+    const data = await response.json();
+    
+    if (data.success && data.valid) {
+      return {
+        content: [
+          {
+            type: 'text',
+            text: `✅ Session is VALID!\n\nSession ID: ${data.session.id}\nCreated: ${new Date(data.session.createdAt).toLocaleString()}\nLast Accessed: ${new Date(data.session.lastAccessed).toLocaleString()}\n\nYou can use this session key for file operations.`,
+          },
+        ],
+      };
+    } else {
+      return {
+        content: [
+          {
+            type: 'text',
+            text: `❌ Session is INVALID or EXPIRED\n\nThe session key you provided is not recognized by the server. This can happen if:\n- The Hugging Face Space restarted\n- The session expired (24 hours old)\n- The session key was mistyped\n\nPlease create a new session using the ReubenOS Session Manager.`,
+          },
+        ],
+      };
+    }
+  }
+
   async uploadFile(args) {
     const formData = new FormData();
     const buffer = Buffer.from(args.content, args.content.includes('base64,') ? 'base64' : 'utf8');