SSH MCP

Instructions

Implementation Reference

• src/ubuntu-website-tools.ts:132-182 (handler)

  The main execution function for the ubuntu_update_packages tool. It uses SSH to run apt-get commands for updating package lists, upgrading packages (optionally security-only), and autoremoving unused packages.
  async ubuntu_update_packages(params) { const { connectionId, securityOnly = false, upgrade = true, autoremove = false, sudo = true } = params; try { const conn = getConnection(connectionMap, connectionId); const sudoPrefix = sudo ? 'sudo ' : ''; // Build the update command let commands = []; // Always update package lists first if (securityOnly) { commands.push(`${sudoPrefix}apt-get update -o Dir::Etc::SourceList=/etc/apt/security.sources.list`); } else { commands.push(`${sudoPrefix}apt-get update`); } // Upgrade if requested if (upgrade) { if (securityOnly) { commands.push(`${sudoPrefix}apt-get upgrade -s | grep "^Inst" | grep -i security | awk '{print $2}' | xargs ${sudoPrefix}apt-get install -y`); } else { commands.push(`${sudoPrefix}apt-get upgrade -y`); } } // Auto-remove if requested if (autoremove) { commands.push(`${sudoPrefix}apt-get autoremove -y`); } // Execute all commands in sequence and collect results let output = ''; for (const cmd of commands) { const result = await executeSSHCommand(conn, cmd, 300000); // 5-minute timeout for upgrades output += `Command: ${cmd}\nExit code: ${result.code}\nOutput:\n${result.stdout || result.stderr}\n\n`; } return { content: [{ type: 'text', text: `Package update completed.\n\n${output}` }] }; } catch (error: any) { return { content: [{ type: 'text', text: `Package update error: ${error.message}` }], isError: true }; } },
• src/ubuntu-website-tools.ts:538-566 (schema)

  Input schema defining parameters for the ubuntu_update_packages tool, including connection ID and optional flags for update behavior.
  ubuntu_update_packages: { description: 'Update system packages on Ubuntu', inputSchema: { type: 'object', properties: { connectionId: { type: 'string', description: 'ID of an active SSH connection' }, securityOnly: { type: 'boolean', description: 'Whether to update only security packages (default: false)' }, upgrade: { type: 'boolean', description: 'Whether to upgrade packages after update (default: true)' }, autoremove: { type: 'boolean', description: 'Whether to remove unused packages after update (default: false)' }, sudo: { type: 'boolean', description: 'Whether to run the command with sudo (default: true)' } }, required: ['connectionId'] } },
• src/index.ts:293-299 (registration)

  Tool dispatch logic in the CallToolRequestSchema handler that routes calls to 'ubuntu_' prefixed tools, including ubuntu_update_packages, to the corresponding handler in ubuntuToolHandlers.
  // Handle Ubuntu tools directly if (toolName.startsWith('ubuntu_') && ubuntuToolHandlers[toolName]) { return ubuntuToolHandlers[toolName](request.params.arguments); } throw new Error(`Unknown tool: ${toolName}`); });
• src/ubuntu-website-tools.ts:18-58 (helper)

  Utility helper function for executing SSH commands with timeout handling, capturing stdout/stderr, and proper error management. Used by the tool handler.
  async function executeSSHCommand(conn: Client, command: string, timeout = 60000): Promise<{ code: number; signal: string; stdout: string; stderr: string; }> { return new Promise((resolve, reject) => { // Set up timeout const timeoutId = setTimeout(() => { reject(new Error(`Command execution timed out after ${timeout}ms`)); }, timeout); conn.exec(command, {}, (err: Error | undefined, stream: any) => { if (err) { clearTimeout(timeoutId); return reject(new Error(`Failed to execute command: ${err.message}`)); } let stdout = ''; let stderr = ''; stream.on('close', (code: number, signal: string) => { clearTimeout(timeoutId); resolve({ code, signal, stdout: stdout.trim(), stderr: stderr.trim() }); }); stream.on('data', (data: Buffer) => { stdout += data.toString(); }); stream.stderr.on('data', (data: Buffer) => { stderr += data.toString(); }); }); }); }