Chapter 28: Building Custom MCP Servers#

use Tina4\McpServer;​$mcp = new McpServer("/api/my-tools", name: "My App Tools", version: "1.0.0");

$mcp->registerRoutes($router);

use Tina4\McpServer;use Tina4\McpTool;​$mcp = new McpServer("/crm/mcp", name: "CRM Tools");​class CrmTools{    #[McpTool("lookup_customer", description: "Find a customer by email", server: "crm")]    public function lookupCustomer(string $email): array    {        global $db;        return $db->fetchOne("SELECT * FROM customers WHERE email = ?", [$email]);    }​    #[McpTool("recent_orders", description: "Get recent orders for a customer", server: "crm")]    public function recentOrders(int $customerId, int $limit = 10): array    {        global $db;        $result = $db->fetch(            "SELECT * FROM orders WHERE customer_id = ? ORDER BY created_at DESC",            [$customerId], $limit        );        return $result->toArray();    }}

{  "name": "lookup_customer",  "description": "Find a customer by email",  "inputSchema": {    "type": "object",    "properties": {      "email": {"type": "string"}    },    "required": ["email"]  }}

use Tina4\McpResource;​class CrmResources{    #[McpResource("crm://product-catalog", description: "All active products", server: "crm")]    public function productCatalog(): array    {        global $db;        return $db->fetch("SELECT id, name, price, category FROM products WHERE active = 1")->toArray();    }​    #[McpResource("crm://tax-rates", description: "Current tax rates by region", server: "crm")]    public function taxRates(): array    {        global $db;        return $db->fetch("SELECT region, rate FROM tax_rates")->toArray();    }}

use Tina4\McpServer;use Tina4\McpTool;​$mcp = new McpServer("/accounting/mcp", name: "Accounting Tools");​class AccountingService{    private $db;​    public function __construct($db)    {        $this->db = $db;    }​    #[McpTool("invoice_lookup", description: "Find an invoice by number", server: "accounting")]    public function lookup(string $invoiceNo): ?array    {        return $this->db->fetchOne(            "SELECT * FROM invoices WHERE invoice_no = ?", [$invoiceNo]        );    }​    #[McpTool("outstanding_balances", description: "List all unpaid invoices", server: "accounting")]    public function balances(float $minAmount = 0.0): array    {        return $this->db->fetch(            "SELECT * FROM invoices WHERE paid = 0 AND total >= ?", [$minAmount]        )->toArray();    }​    #[McpTool("monthly_summary", description: "Revenue summary for a month", server: "accounting")]    public function summary(int $year, int $month): ?array    {        return $this->db->fetchOne(            "SELECT SUM(total) as revenue, COUNT(*) as invoice_count "            . "FROM invoices WHERE strftime('%Y', created_at) = ? "            . "AND strftime('%m', created_at) = ?",            [(string)$year, str_pad($month, 2, '0', STR_PAD_LEFT)]        );    }}​// Create the service instance - methods are already registered via attributes$accounting = new AccountingService($db);

use Tina4\Secured;use Tina4\Middleware;​// Secure the entire MCP path#[Secured]#[Middleware(AuthMiddleware::class)]function registerMcp() {    global $mcp, $router;    $mcp->registerRoutes($router);}

#[McpTool("sensitive_data", description: "Access restricted data", server: "crm")]public function sensitiveData(string $token): array{    global $db;    $payload = Auth::validToken($token);    if (!$payload) {        return ["error" => "Unauthorized"];    }    return $db->fetch("SELECT * FROM sensitive_table")->toArray();}

// Test the tool method directlypublic function testLookupCustomer(): void{    $tools = new CrmTools();    $result = $tools->lookupCustomer("alice@example.com");    $this->assertNotNull($result);    $this->assertEquals("alice@example.com", $result["email"]);}​// Test via MCP protocolpublic function testMcpToolCall(): void{    $resp = json_decode($mcp->handleMessage([        "jsonrpc" => "2.0",        "id" => 1,        "method" => "tools/call",        "params" => [            "name" => "lookup_customer",            "arguments" => ["email" => "alice@example.com"]        ]    ]), true);    $this->assertArrayHasKey("result", $resp);    $content = $resp["result"]["content"][0]["text"];    $this->assertStringContainsString("alice", strtolower($content));}

<?php// app.phprequire_once "vendor/autoload.php";​use Tina4\McpServer;use Tina4\McpTool;use Tina4\McpResource;use Tina4\Database;use Tina4\ORM;​$db = new Database("sqlite:///crm.db");ORM::bind($db);​// Create MCP server$crmMcp = new McpServer("/crm/mcp", name: "CRM Assistant", version: "1.0.0");​class CrmService{    private $db;​    public function __construct($db)    {        $this->db = $db;    }​    // Tools    #[McpTool("find_customer", description: "Search customers by name or email", server: "crm")]    public function findCustomer(string $query): array    {        return $this->db->fetch(            "SELECT * FROM customers WHERE name LIKE ? OR email LIKE ?",            ["%{$query}%", "%{$query}%"]        )->toArray();    }​    #[McpTool("customer_orders", description: "Get all orders for a customer", server: "crm")]    public function customerOrders(int $customerId): array    {        return $this->db->fetch(            "SELECT o.*, GROUP_CONCAT(oi.product_name) as items "            . "FROM orders o LEFT JOIN order_items oi ON o.id = oi.order_id "            . "WHERE o.customer_id = ? GROUP BY o.id ORDER BY o.created_at DESC",            [$customerId]        )->toArray();    }​    #[McpTool("create_note", description: "Add a note to a customer record", server: "crm")]    public function createNote(int $customerId, string $note): array    {        $this->db->insert("customer_notes", ["customer_id" => $customerId, "note" => $note]);        return ["success" => true];    }​    // Resources    #[McpResource("crm://products", description: "Product catalog", server: "crm")]    public function products(): array    {        return $this->db->fetch("SELECT * FROM products WHERE active = 1")->toArray();    }​    #[McpResource("crm://stats", description: "CRM statistics", server: "crm")]    public function stats(): array    {        $customers = $this->db->fetchOne("SELECT COUNT(*) as count FROM customers");        $orders = $this->db->fetchOne("SELECT COUNT(*) as count, SUM(total) as revenue FROM orders");        return [            "customers" => $customers["count"],            "orders" => $orders["count"],            "revenue" => $orders["revenue"],        ];    }}​// Create the service and register routes$crm = new CrmService($db);$crmMcp->registerRoutes($router);​Tina4\run();