mcp-core.php
5 months ago
mcp-rest.php
1 year ago
mcp.conf
1 year ago
mcp.js
8 months ago
mcp.md
8 months ago
mcp.php
5 months ago
mcp.php
1400 lines
| 1 | <?php |
| 2 | |
| 3 | /** |
| 4 | * AI Engine MCP Server |
| 5 | * |
| 6 | * This class implements a Model Context Protocol (MCP) server for AI Engine. |
| 7 | * |
| 8 | * Current Implementation: |
| 9 | * - Works reliably with Claude App through the mcp.js relay |
| 10 | * - Works directly with Claude.ai and ChatGPT via SSE connections |
| 11 | * - Properly handles agent cancellation signals (notifications/cancelled) to free workers immediately |
| 12 | * - Uses 30-second timeout to prevent worker exhaustion from abandoned connections |
| 13 | * - Sends heartbeat signals to detect dead connections quickly |
| 14 | * - OAuth authentication flow is currently disabled due to security concerns |
| 15 | * (only static bearer tokens are supported) |
| 16 | * |
| 17 | * Connection Management: |
| 18 | * - Agents send notifications/cancelled when done, triggering immediate SSE closure |
| 19 | * - 30-second timeout ensures workers are freed even if agents forget to disconnect |
| 20 | * - Heartbeat comments (every 10s) help proxies and connection_aborted() detect dead sockets |
| 21 | * - Both the mcp.js relay and direct agent connections work reliably |
| 22 | */ |
| 23 | |
| 24 | class Meow_MWAI_Labs_MCP { |
| 25 | private $core = null; |
| 26 | private $namespace = 'mcp/v1'; |
| 27 | private $server_version = '0.0.1'; |
| 28 | private $protocol_version = '2025-06-18'; // Updated to match official MCP SDK |
| 29 | private $queue_key = 'mwai_mcp_msg'; |
| 30 | private $session_id = null; |
| 31 | private $logging = false; |
| 32 | private $last_action_time = 0; |
| 33 | private $bearer_token = null; |
| 34 | // Placeholder for OAuth integration. Currently unused and kept for |
| 35 | // future implementation once the security model is revised. |
| 36 | private $oauth = null; |
| 37 | |
| 38 | #region Initialize |
| 39 | public function __construct( $core ) { |
| 40 | $this->core = $core; |
| 41 | |
| 42 | // Set logging based on option |
| 43 | $this->logging = $this->core->get_option( 'mcp_debug_mode', false ); |
| 44 | |
| 45 | // OAuth support is temporarily disabled due to security concerns. |
| 46 | // The previous implementation allowed unvalidated redirect URIs which |
| 47 | // introduced an open redirect vulnerability and the possibility to |
| 48 | // steal authorization codes. Until proper client registration with |
| 49 | // strict redirect URI validation is implemented, the OAuth feature is |
| 50 | // not loaded. See labs/oauth.php for the previous code and take care |
| 51 | // when re‑enabling it in the future. |
| 52 | |
| 53 | add_action( 'rest_api_init', [ $this, 'rest_api_init' ] ); |
| 54 | } |
| 55 | |
| 56 | public function is_logging_enabled() { |
| 57 | return $this->logging; |
| 58 | } |
| 59 | |
| 60 | public function rest_api_init() { |
| 61 | // Load bearer token if not already loaded |
| 62 | if ( $this->bearer_token === null ) { |
| 63 | $this->bearer_token = $this->core->get_option( 'mcp_bearer_token' ); |
| 64 | } |
| 65 | |
| 66 | // Only add filter once |
| 67 | static $filter_added = false; |
| 68 | if ( !empty( $this->bearer_token ) && !$filter_added ) { |
| 69 | add_filter( 'mwai_allow_mcp', [ $this, 'auth_via_bearer_token' ], 10, 2 ); |
| 70 | $filter_added = true; |
| 71 | } |
| 72 | register_rest_route( $this->namespace, '/sse', [ |
| 73 | 'methods' => [ 'GET', 'POST', 'HEAD' ], // Support HEAD for client endpoint checks |
| 74 | 'callback' => [ $this, 'handle_sse' ], |
| 75 | 'permission_callback' => function ( $request ) { |
| 76 | return $this->can_access_mcp( $request ); |
| 77 | }, |
| 78 | ] ); |
| 79 | |
| 80 | register_rest_route( $this->namespace, '/messages', [ |
| 81 | 'methods' => 'POST', |
| 82 | 'callback' => [ $this, 'handle_message' ], |
| 83 | 'permission_callback' => function ( $request ) { |
| 84 | return $this->can_access_mcp( $request ); |
| 85 | }, |
| 86 | ] ); |
| 87 | |
| 88 | // No-Auth URL endpoints (with token in path) - Legacy SSE |
| 89 | $noauth_enabled = $this->core->get_option( 'mcp_noauth_url' ); |
| 90 | if ( $noauth_enabled && !empty( $this->bearer_token ) ) { |
| 91 | register_rest_route( $this->namespace, '/' . $this->bearer_token . '/sse', [ |
| 92 | 'methods' => 'GET', |
| 93 | 'callback' => [ $this, 'handle_sse' ], |
| 94 | 'permission_callback' => function ( $request ) { |
| 95 | return $this->handle_noauth_access( $request ); |
| 96 | }, |
| 97 | 'show_in_index' => false, |
| 98 | ] ); |
| 99 | |
| 100 | register_rest_route( $this->namespace, '/' . $this->bearer_token . '/sse', [ |
| 101 | 'methods' => 'POST', |
| 102 | 'callback' => [ $this, 'handle_sse' ], |
| 103 | 'permission_callback' => function ( $request ) { |
| 104 | return $this->handle_noauth_access( $request ); |
| 105 | }, |
| 106 | 'show_in_index' => false, |
| 107 | ] ); |
| 108 | |
| 109 | register_rest_route( $this->namespace, '/' . $this->bearer_token . '/messages', [ |
| 110 | 'methods' => 'POST', |
| 111 | 'callback' => [ $this, 'handle_message' ], |
| 112 | 'permission_callback' => function ( $request ) { |
| 113 | return $this->handle_noauth_access( $request ); |
| 114 | }, |
| 115 | 'show_in_index' => false, |
| 116 | ] ); |
| 117 | } |
| 118 | |
| 119 | // Streamable HTTP endpoint (Modern transport for Claude Code) |
| 120 | // Uses Authorization: Bearer header for authentication |
| 121 | // Automatically enabled when MCP module is active and bearer token is set |
| 122 | if ( !empty( $this->bearer_token ) ) { |
| 123 | // Main endpoint with Authorization header (at /http path) |
| 124 | register_rest_route( $this->namespace, '/http', [ |
| 125 | 'methods' => [ 'GET', 'POST', 'DELETE' ], |
| 126 | 'callback' => [ $this, 'handle_streamable_http' ], |
| 127 | 'permission_callback' => function ( $request ) { |
| 128 | return $this->can_access_mcp( $request ); |
| 129 | }, |
| 130 | 'show_in_index' => false, |
| 131 | ] ); |
| 132 | |
| 133 | // Alternative endpoint with token in URL (for clients that don't support headers) |
| 134 | register_rest_route( $this->namespace, '/' . $this->bearer_token, [ |
| 135 | 'methods' => [ 'GET', 'POST', 'DELETE' ], |
| 136 | 'callback' => [ $this, 'handle_streamable_http' ], |
| 137 | 'permission_callback' => function ( $request ) { |
| 138 | return $this->handle_noauth_access_streamable( $request ); |
| 139 | }, |
| 140 | 'show_in_index' => false, |
| 141 | ] ); |
| 142 | } |
| 143 | } |
| 144 | #endregion |
| 145 | |
| 146 | #region Auth (Bearer token) |
| 147 | /** |
| 148 | * SECURITY: MCP provides powerful WordPress management capabilities, so access must be strictly controlled. |
| 149 | * |
| 150 | * By default, only administrators can access MCP endpoints. This prevents lower-privileged users |
| 151 | * (subscribers, contributors, etc.) from executing dangerous operations like creating admin users, |
| 152 | * deleting content, or modifying settings. |
| 153 | * |
| 154 | * When a bearer token is configured, it overrides the default admin check, but access is DENIED |
| 155 | * unless a valid token is provided. This ensures MCP is secure even with default settings. |
| 156 | */ |
| 157 | public function can_access_mcp( $request ) { |
| 158 | // Default to requiring administrator capability for security |
| 159 | $is_admin = current_user_can( 'administrator' ); |
| 160 | return apply_filters( 'mwai_allow_mcp', $is_admin, $request ); |
| 161 | } |
| 162 | |
| 163 | public function auth_via_bearer_token( $allow, $request ) { |
| 164 | // Skip if already authenticated as admin |
| 165 | if ( $allow ) { |
| 166 | return $allow; |
| 167 | } |
| 168 | |
| 169 | $hdr = $request->get_header( 'authorization' ); |
| 170 | |
| 171 | // If no authorization header but bearer token is configured, deny access |
| 172 | if ( !$hdr && !empty( $this->bearer_token ) ) { |
| 173 | if ( $this->logging ) { |
| 174 | error_log( '[AI Engine MCP] ❌ No authorization header provided. Server may be stripping headers.' ); |
| 175 | } |
| 176 | return false; |
| 177 | } |
| 178 | |
| 179 | // Check for Bearer token in header |
| 180 | if ( $hdr && preg_match( '/Bearer\s+(.+)/i', $hdr, $m ) ) { |
| 181 | $token = trim( $m[1] ); |
| 182 | $auth_result = 'none'; |
| 183 | |
| 184 | // Check if it's an OAuth token |
| 185 | if ( $this->oauth ) { |
| 186 | $token_data = $this->oauth->validate_token( $token ); |
| 187 | if ( $token_data ) { |
| 188 | // Set current user based on OAuth token |
| 189 | wp_set_current_user( $token_data['user_id'] ); |
| 190 | $auth_result = 'oauth'; |
| 191 | // Only log auth for SSE endpoint |
| 192 | if ( $this->logging && strpos( $request->get_route(), '/sse' ) !== false ) { |
| 193 | error_log( '[AI Engine MCP] 🔐 OAuth OK (user: ' . $token_data['user_id'] . ')' ); |
| 194 | } |
| 195 | return true; |
| 196 | } |
| 197 | } |
| 198 | |
| 199 | // Fall back to static bearer token if configured |
| 200 | if ( !empty( $this->bearer_token ) && hash_equals( $this->bearer_token, $token ) ) { |
| 201 | if ( $admin = $this->core->get_admin_user() ) { |
| 202 | wp_set_current_user( $admin->ID, $admin->user_login ); |
| 203 | } |
| 204 | $auth_result = 'static'; |
| 205 | if ( $this->logging ) { |
| 206 | error_log( '[AI Engine MCP] 🔐 Bearer token auth OK' ); |
| 207 | } |
| 208 | return true; |
| 209 | } |
| 210 | |
| 211 | if ( $this->logging && $auth_result === 'none' ) { |
| 212 | error_log( '[AI Engine MCP] ❌ Bearer token invalid.' ); |
| 213 | } |
| 214 | // Explicitly deny access for invalid tokens |
| 215 | return false; |
| 216 | } |
| 217 | |
| 218 | // ?token=xyz fallback (optional) - only for static bearer token |
| 219 | if ( !empty( $this->bearer_token ) ) { |
| 220 | $q = sanitize_text_field( $request->get_param( 'token' ) ); |
| 221 | if ( $q && hash_equals( $this->bearer_token, $q ) ) { |
| 222 | if ( $admin = $this->core->get_admin_user() ) { |
| 223 | wp_set_current_user( $admin->ID, $admin->user_login ); |
| 224 | } |
| 225 | return true; |
| 226 | } |
| 227 | } |
| 228 | |
| 229 | // If bearer token is configured but no valid auth provided, deny access |
| 230 | if ( !empty( $this->bearer_token ) ) { |
| 231 | return false; |
| 232 | } |
| 233 | |
| 234 | return $allow; |
| 235 | } |
| 236 | |
| 237 | public function handle_noauth_access( $request ) { |
| 238 | // For no-auth URLs, the token is already verified by being in the URL path |
| 239 | // Double-check that the route actually contains the token |
| 240 | $route = $request->get_route(); |
| 241 | if ( strpos( $route, '/' . $this->bearer_token . '/' ) === false ) { |
| 242 | if ( $this->logging ) { |
| 243 | error_log( '[AI Engine MCP] ❌ Invalid no-auth URL access attempt.' ); |
| 244 | } |
| 245 | return false; |
| 246 | } |
| 247 | |
| 248 | // Set the current user to admin since token is valid |
| 249 | if ( $admin = $this->core->get_admin_user() ) { |
| 250 | wp_set_current_user( $admin->ID, $admin->user_login ); |
| 251 | } |
| 252 | return true; |
| 253 | } |
| 254 | |
| 255 | public function handle_noauth_access_streamable( $request ) { |
| 256 | // For Streamable HTTP with token in URL path (no trailing slash) |
| 257 | $route = $request->get_route(); |
| 258 | $expected = '/' . $this->namespace . '/' . $this->bearer_token; |
| 259 | if ( $route !== $expected ) { |
| 260 | if ( $this->logging ) { |
| 261 | error_log( '[AI Engine MCP] ❌ Invalid Streamable HTTP no-auth URL access attempt.' ); |
| 262 | } |
| 263 | return false; |
| 264 | } |
| 265 | |
| 266 | // Set the current user to admin since token is valid |
| 267 | if ( $admin = $this->core->get_admin_user() ) { |
| 268 | wp_set_current_user( $admin->ID, $admin->user_login ); |
| 269 | } |
| 270 | return true; |
| 271 | } |
| 272 | |
| 273 | #endregion |
| 274 | |
| 275 | #region Helpers (log / JSON-RPC utils) |
| 276 | private function log( $msg ) { |
| 277 | // This method is for internal UI logs - keep it minimal |
| 278 | if ( $this->logging ) { |
| 279 | // Only log important messages to UI |
| 280 | if ( strpos( $msg, 'queued' ) === false && strpos( $msg, 'flush' ) === false ) { |
| 281 | Meow_MWAI_Logging::log( "[AI Engine MCP] {$msg}" ); |
| 282 | } |
| 283 | } |
| 284 | } |
| 285 | |
| 286 | /** Wrap a JSON-RPC error object */ |
| 287 | private function rpc_error( $id, int $code, string $msg, $extra = null ): array { |
| 288 | $err = [ 'code' => $code, 'message' => $msg ]; |
| 289 | if ( $extra !== null ) { |
| 290 | $err['data'] = $extra; |
| 291 | } |
| 292 | return [ 'jsonrpc' => '2.0', 'id' => $id, 'error' => $err ]; |
| 293 | } |
| 294 | |
| 295 | /** Queue an error for SSE delivery */ |
| 296 | private function queue_error( $sess, $id, int $code, string $msg, $extra = null ): void { |
| 297 | $this->store_message( $sess, $this->rpc_error( $id, $code, $msg, $extra ) ); |
| 298 | } |
| 299 | |
| 300 | /** Format tool result for MCP protocol */ |
| 301 | private function format_tool_result( $result ): array { |
| 302 | // If result is a string, wrap it in the MCP content format |
| 303 | if ( is_string( $result ) ) { |
| 304 | return [ |
| 305 | 'content' => [ |
| 306 | [ |
| 307 | 'type' => 'text', |
| 308 | 'text' => $result, |
| 309 | ], |
| 310 | ], |
| 311 | ]; |
| 312 | } |
| 313 | |
| 314 | // If result has 'content' key, assume it's already properly formatted |
| 315 | if ( is_array( $result ) && isset( $result['content'] ) ) { |
| 316 | return $result; |
| 317 | } |
| 318 | |
| 319 | // If result is an array without 'content' key, wrap it as JSON |
| 320 | if ( is_array( $result ) ) { |
| 321 | return [ |
| 322 | 'content' => [ |
| 323 | [ |
| 324 | 'type' => 'text', |
| 325 | 'text' => wp_json_encode( $result, JSON_PRETTY_PRINT ), |
| 326 | ], |
| 327 | ], |
| 328 | 'data' => $result, |
| 329 | ]; |
| 330 | } |
| 331 | |
| 332 | // For any other type, convert to string and wrap |
| 333 | return [ |
| 334 | 'content' => [ |
| 335 | [ |
| 336 | 'type' => 'text', |
| 337 | 'text' => (string) $result, |
| 338 | ], |
| 339 | ], |
| 340 | ]; |
| 341 | } |
| 342 | #endregion |
| 343 | |
| 344 | #region Handle direct JSON-RPC (for Claude's MCP client) |
| 345 | /** |
| 346 | * Claude's MCP client (via Anthropic API) sends JSON-RPC requests directly to the SSE endpoint |
| 347 | * as POST requests, rather than following the typical SSE flow: |
| 348 | * - Normal flow: GET /sse → establish SSE stream → POST /messages for JSON-RPC |
| 349 | * - Claude's flow: POST /sse with JSON-RPC body → expect immediate JSON response |
| 350 | * |
| 351 | * This method handles the direct JSON-RPC requests to maintain compatibility with Claude. |
| 352 | */ |
| 353 | private function handle_direct_jsonrpc( WP_REST_Request $request, $data ) { |
| 354 | $id = $data['id'] ?? null; |
| 355 | $method = $data['method'] ?? null; |
| 356 | |
| 357 | if ( json_last_error() !== JSON_ERROR_NONE ) { |
| 358 | $response = new WP_REST_Response( [ |
| 359 | 'jsonrpc' => '2.0', |
| 360 | 'id' => null, |
| 361 | 'error' => [ 'code' => -32700, 'message' => 'Parse error: invalid JSON' ] |
| 362 | ], 200 ); |
| 363 | $response->set_headers( [ 'Content-Type' => 'application/json' ] ); |
| 364 | $session_header = $request->get_header( 'mcp-session-id' ); |
| 365 | if ( !empty( $session_header ) ) { |
| 366 | return $this->attach_session_header( $response, sanitize_text_field( $session_header ) ); |
| 367 | } |
| 368 | return $response; |
| 369 | } |
| 370 | |
| 371 | if ( !is_array( $data ) || !$method ) { |
| 372 | $response = new WP_REST_Response( [ |
| 373 | 'jsonrpc' => '2.0', |
| 374 | 'id' => $id, |
| 375 | 'error' => [ 'code' => -32600, 'message' => 'Invalid Request' ] |
| 376 | ], 200 ); |
| 377 | $response->set_headers( [ 'Content-Type' => 'application/json' ] ); |
| 378 | $session_header = $request->get_header( 'mcp-session-id' ); |
| 379 | if ( !empty( $session_header ) ) { |
| 380 | return $this->attach_session_header( $response, sanitize_text_field( $session_header ) ); |
| 381 | } |
| 382 | return $response; |
| 383 | } |
| 384 | |
| 385 | $session_header = $request->get_header( 'mcp-session-id' ); |
| 386 | $session_id = ''; |
| 387 | if ( !empty( $session_header ) ) { |
| 388 | $session_id = sanitize_text_field( $session_header ); |
| 389 | } |
| 390 | |
| 391 | if ( $method === 'initialize' || empty( $session_id ) ) { |
| 392 | $session_id = wp_generate_uuid4(); |
| 393 | if ( $this->logging ) { |
| 394 | error_log( '[AI Engine MCP] 🆔 Direct session initialized: ' . $session_id ); |
| 395 | } |
| 396 | } |
| 397 | |
| 398 | try { |
| 399 | $reply = null; |
| 400 | |
| 401 | switch ( $method ) { |
| 402 | case 'initialize': |
| 403 | // Check if client requests a specific protocol version |
| 404 | $params = $data['params'] ?? []; |
| 405 | $requested_version = $params['protocolVersion'] ?? null; |
| 406 | $client_info = $params['clientInfo'] ?? null; |
| 407 | |
| 408 | if ( $this->logging && $client_info ) { |
| 409 | $client_name = $client_info['name'] ?? 'unknown'; |
| 410 | $client_version = $client_info['version'] ?? 'unknown'; |
| 411 | error_log( "[AI Engine MCP] Client: {$client_name} v{$client_version}" ); |
| 412 | } |
| 413 | |
| 414 | if ( $requested_version && $requested_version !== $this->protocol_version ) { |
| 415 | if ( $this->logging ) { |
| 416 | Meow_MWAI_Logging::warn( "[AI Engine MCP] Client requested protocol version {$requested_version}, but we only support {$this->protocol_version}" ); |
| 417 | } |
| 418 | } |
| 419 | |
| 420 | $reply = [ |
| 421 | 'jsonrpc' => '2.0', |
| 422 | 'id' => $id, |
| 423 | 'result' => [ |
| 424 | 'protocolVersion' => $this->protocol_version, |
| 425 | 'serverInfo' => (object) [ |
| 426 | 'name' => 'AI Engine - ' . get_bloginfo( 'name' ), |
| 427 | 'version' => $this->server_version, |
| 428 | ], |
| 429 | 'capabilities' => (object) [ |
| 430 | 'tools' => new stdClass(), // Empty object, matching official SDK |
| 431 | ], |
| 432 | ], |
| 433 | ]; |
| 434 | break; |
| 435 | |
| 436 | case 'tools/list': |
| 437 | $tools = $this->get_tools_list(); |
| 438 | |
| 439 | // Debug logging for tools/list |
| 440 | if ( $this->logging ) { |
| 441 | $user_agent = isset( $_SERVER['HTTP_USER_AGENT'] ) ? $_SERVER['HTTP_USER_AGENT'] : 'unknown'; |
| 442 | error_log( '[AI Engine MCP Direct] 📋 tools/list requested by: ' . $user_agent ); |
| 443 | error_log( '[AI Engine MCP Direct] 📊 Returning ' . count( $tools ) . ' tools' ); |
| 444 | if ( count( $tools ) > 0 ) { |
| 445 | $tool_names = array_column( $tools, 'name' ); |
| 446 | error_log( '[AI Engine MCP Direct] 🛠️ Tool names: ' . implode( ', ', $tool_names ) ); |
| 447 | } |
| 448 | else { |
| 449 | error_log( '[AI Engine MCP Direct] ⚠️ WARNING: No tools returned!' ); |
| 450 | } |
| 451 | } |
| 452 | |
| 453 | $reply = [ |
| 454 | 'jsonrpc' => '2.0', |
| 455 | 'id' => $id, |
| 456 | 'result' => [ 'tools' => $tools ], |
| 457 | ]; |
| 458 | break; |
| 459 | |
| 460 | case 'tools/call': |
| 461 | $params = $data['params'] ?? []; |
| 462 | $tool = $params['name'] ?? ''; |
| 463 | $arguments = $params['arguments'] ?? []; |
| 464 | |
| 465 | if ( $this->logging ) { |
| 466 | error_log( '[AI Engine MCP Direct] 🔧 tools/call - Tool: ' . $tool ); |
| 467 | error_log( '[AI Engine MCP Direct] 🔧 tools/call - Arguments: ' . wp_json_encode( $arguments ) ); |
| 468 | } |
| 469 | |
| 470 | try { |
| 471 | $reply = $this->execute_tool( $tool, $arguments, $id ); |
| 472 | if ( $this->logging ) { |
| 473 | error_log( '[AI Engine MCP Direct] � |
| 474 | tools/call - Success for tool: ' . $tool ); |
| 475 | } |
| 476 | } |
| 477 | catch ( Exception $e ) { |
| 478 | if ( $this->logging ) { |
| 479 | error_log( '[AI Engine MCP Direct] ❌ tools/call - Error: ' . $e->getMessage() ); |
| 480 | } |
| 481 | throw $e; |
| 482 | } |
| 483 | break; |
| 484 | |
| 485 | case 'notifications/initialized': |
| 486 | // This is a notification from the client indicating it has initialized |
| 487 | // No response needed for notifications |
| 488 | // Client initialized - no need to log |
| 489 | return $this->attach_session_header( new WP_REST_Response( null, 204 ), $session_id ); |
| 490 | break; |
| 491 | |
| 492 | default: |
| 493 | // Check if it's a notification (no id) |
| 494 | if ( $id === null && strpos( $method, 'notifications/' ) === 0 ) { |
| 495 | if ( $this->logging ) { |
| 496 | error_log( '[AI Engine MCP] 📨 Notification received: ' . $method ); |
| 497 | } |
| 498 | return $this->attach_session_header( new WP_REST_Response( null, 204 ), $session_id ); |
| 499 | } |
| 500 | |
| 501 | $reply = [ |
| 502 | 'jsonrpc' => '2.0', |
| 503 | 'id' => $id, |
| 504 | 'error' => [ 'code' => -32601, 'message' => "Method not found: {$method}" ] |
| 505 | ]; |
| 506 | } |
| 507 | |
| 508 | // Ensure proper JSON-RPC response |
| 509 | $response = new WP_REST_Response( $reply, 200 ); |
| 510 | $response->set_headers( [ 'Content-Type' => 'application/json' ] ); |
| 511 | return $this->attach_session_header( $response, $session_id ); |
| 512 | |
| 513 | } |
| 514 | catch ( Exception $e ) { |
| 515 | if ( $this->logging ) { |
| 516 | error_log( '[AI Engine MCP] ❌ Exception in handle_direct_jsonrpc: ' . $e->getMessage() ); |
| 517 | } |
| 518 | |
| 519 | $error_response = new WP_REST_Response( [ |
| 520 | 'jsonrpc' => '2.0', |
| 521 | 'id' => $id, |
| 522 | 'error' => [ 'code' => -32603, 'message' => 'Internal error', 'data' => $e->getMessage() ] |
| 523 | ], 200 ); |
| 524 | $error_response->set_headers( [ 'Content-Type' => 'application/json' ] ); |
| 525 | return $this->attach_session_header( $error_response, $session_id ); |
| 526 | } |
| 527 | } |
| 528 | #endregion |
| 529 | |
| 530 | #region Handle SSE (stream loop) |
| 531 | private function reply( string $event, $data = null, string $enc = 'json' ) { |
| 532 | // Handle special events |
| 533 | if ( $event === 'bye' ) { |
| 534 | echo "event: bye\ndata: \n\n"; |
| 535 | if ( ob_get_level() ) { |
| 536 | ob_end_flush(); |
| 537 | } |
| 538 | flush(); |
| 539 | $this->last_action_time = time(); |
| 540 | $this->log( 'Clean disconnection' ); |
| 541 | return; |
| 542 | } |
| 543 | |
| 544 | if ( $enc === 'json' && $data === null ) { |
| 545 | $this->log( "no data for {$event}" ); |
| 546 | return; |
| 547 | } |
| 548 | echo "event: {$event}\n"; |
| 549 | if ( $enc === 'json' ) { |
| 550 | $data = $data === null ? '{}' : wp_json_encode( $data, JSON_UNESCAPED_UNICODE ); |
| 551 | } |
| 552 | echo 'data: ' . $data . "\n\n"; |
| 553 | |
| 554 | if ( ob_get_level() ) { |
| 555 | ob_end_flush(); |
| 556 | } |
| 557 | flush(); |
| 558 | |
| 559 | $this->last_action_time = time(); |
| 560 | // Only log endpoint announcements |
| 561 | if ( $event === 'endpoint' ) { |
| 562 | $this->log( 'SSE endpoint ready' ); |
| 563 | } |
| 564 | } |
| 565 | |
| 566 | private function generate_sse_id( $req ) { |
| 567 | $last = $req ? $req->get_header( 'last-event-id' ) : ''; |
| 568 | return $last ?: str_replace( '-', '', wp_generate_uuid4() ); |
| 569 | } |
| 570 | |
| 571 | private function attach_session_header( WP_REST_Response $response, string $session_id ) { |
| 572 | if ( empty( $session_id ) ) { |
| 573 | return $response; |
| 574 | } |
| 575 | |
| 576 | $response->header( 'Mcp-Session-Id', $session_id ); |
| 577 | |
| 578 | if ( $this->logging ) { |
| 579 | error_log( '[AI Engine MCP] 🪪 Response session header: ' . $session_id ); |
| 580 | } |
| 581 | |
| 582 | return $response; |
| 583 | } |
| 584 | |
| 585 | public function handle_sse( WP_REST_Request $request ) { |
| 586 | // Handle HEAD request - just confirm endpoint exists |
| 587 | if ( $request->get_method() === 'HEAD' ) { |
| 588 | return new WP_REST_Response( null, 200, [ |
| 589 | 'Content-Type' => 'text/event-stream', |
| 590 | 'Cache-Control' => 'no-cache', |
| 591 | ] ); |
| 592 | } |
| 593 | |
| 594 | $raw_body = $request->get_body(); |
| 595 | |
| 596 | // Handle POST request with JSON-RPC body (Direct MCP client behavior) |
| 597 | // Both Claude.ai and OpenAI/ChatGPT send JSON-RPC requests directly to the SSE endpoint |
| 598 | // instead of establishing an SSE connection first. This is non-standard but we need to support it. |
| 599 | // Expected flow: GET /sse (establish stream) → POST /messages (send JSON-RPC) |
| 600 | // Actual flow: POST /sse with JSON-RPC body → expects immediate JSON response |
| 601 | if ( $request->get_method() === 'POST' && !empty( $raw_body ) ) { |
| 602 | $data = json_decode( $raw_body, true ); |
| 603 | if ( $data && isset( $data['method'] ) ) { |
| 604 | // Don't log here - it's already logged by log_requests() |
| 605 | // Process as a direct JSON-RPC request instead of starting SSE stream |
| 606 | return $this->handle_direct_jsonrpc( $request, $data ); |
| 607 | } |
| 608 | } |
| 609 | |
| 610 | @ini_set( 'zlib.output_compression', '0' ); |
| 611 | @ini_set( 'output_buffering', '0' ); |
| 612 | @ini_set( 'implicit_flush', '1' ); |
| 613 | if ( function_exists( 'ob_implicit_flush' ) ) { |
| 614 | ob_implicit_flush( true ); |
| 615 | } |
| 616 | |
| 617 | header( 'Content-Type: text/event-stream' ); |
| 618 | header( 'Cache-Control: no-cache' ); |
| 619 | header( 'X-Accel-Buffering: no' ); |
| 620 | header( 'Connection: keep-alive' ); |
| 621 | while ( ob_get_level() ) { |
| 622 | ob_end_flush(); |
| 623 | } |
| 624 | |
| 625 | /* — greet client —*/ |
| 626 | $this->session_id = $this->generate_sse_id( $request ); |
| 627 | $this->last_action_time = time(); |
| 628 | echo "id: {$this->session_id}\n\n"; |
| 629 | flush(); |
| 630 | |
| 631 | $msg_uri = sprintf( |
| 632 | '%s/messages?session_id=%s', |
| 633 | rest_url( $this->namespace ), |
| 634 | $this->session_id |
| 635 | ); |
| 636 | $this->reply( 'endpoint', $msg_uri, 'text' ); |
| 637 | if ( $this->logging ) { |
| 638 | error_log( '[AI Engine MCP] � |
| 639 | SSE connected (' . substr( $this->session_id, 0, 8 ) . '...)' ); |
| 640 | } |
| 641 | |
| 642 | /* — main loop —*/ |
| 643 | while ( true ) { |
| 644 | // Reduced timeout to free workers faster when agents disconnect |
| 645 | $max_time = $this->logging ? 30 : 60 * 3; // 30 seconds in debug, 3 minutes in production |
| 646 | $idle = ( time() - $this->last_action_time ) >= $max_time; |
| 647 | if ( connection_aborted() || $idle ) { |
| 648 | $this->reply( 'bye' ); |
| 649 | if ( $this->logging ) { |
| 650 | error_log( '[AI Engine MCP] 🔚 SSE closed (' . ( $idle ? 'idle' : 'abort' ) . ')' ); |
| 651 | } |
| 652 | break; |
| 653 | } |
| 654 | |
| 655 | // Send heartbeat every 10 seconds to detect dead connections |
| 656 | $time_since_last = time() - $this->last_action_time; |
| 657 | if ( $time_since_last >= 10 && $time_since_last % 10 === 0 ) { |
| 658 | echo ": heartbeat\n\n"; |
| 659 | if ( ob_get_level() ) { |
| 660 | ob_end_flush(); |
| 661 | } |
| 662 | flush(); |
| 663 | } |
| 664 | |
| 665 | foreach ( $this->fetch_messages( $this->session_id ) as $p ) { |
| 666 | // Check for kill signal in the message queue |
| 667 | if ( isset( $p['method'] ) && $p['method'] === 'mwai/kill' ) { |
| 668 | if ( $this->logging ) { |
| 669 | error_log( '[AI Engine MCP] Kill signal - terminating' ); |
| 670 | } |
| 671 | $this->reply( 'bye' ); |
| 672 | exit; |
| 673 | } |
| 674 | |
| 675 | // Don't log SSE responses - they clutter the logs |
| 676 | $this->reply( 'message', $p ); |
| 677 | } |
| 678 | |
| 679 | usleep( 200000 ); // 200 ms |
| 680 | } |
| 681 | exit; |
| 682 | } |
| 683 | #endregion |
| 684 | |
| 685 | #region Handle Streamable HTTP (Modern MCP transport) |
| 686 | /** |
| 687 | * Handle Streamable HTTP requests per MCP specification. |
| 688 | * This is the modern transport used by Claude Code and other MCP clients. |
| 689 | * |
| 690 | * - POST: Send JSON-RPC request, receive JSON response (or SSE for streaming) |
| 691 | * - GET: Open SSE stream for server-initiated messages |
| 692 | * - DELETE: Terminate the session |
| 693 | * |
| 694 | * @see https://modelcontextprotocol.io/specification/2025-03-26/basic/transports#streamable-http |
| 695 | */ |
| 696 | public function handle_streamable_http( WP_REST_Request $request ) { |
| 697 | $method = $request->get_method(); |
| 698 | |
| 699 | switch ( $method ) { |
| 700 | case 'POST': |
| 701 | return $this->handle_streamable_http_post( $request ); |
| 702 | |
| 703 | case 'GET': |
| 704 | return $this->handle_streamable_http_get( $request ); |
| 705 | |
| 706 | case 'DELETE': |
| 707 | return $this->handle_streamable_http_delete( $request ); |
| 708 | |
| 709 | default: |
| 710 | return new WP_REST_Response( [ |
| 711 | 'error' => 'Method not allowed' |
| 712 | ], 405 ); |
| 713 | } |
| 714 | } |
| 715 | |
| 716 | /** |
| 717 | * Handle POST requests for Streamable HTTP. |
| 718 | * This processes JSON-RPC requests and returns JSON responses. |
| 719 | */ |
| 720 | private function handle_streamable_http_post( WP_REST_Request $request ) { |
| 721 | $raw_body = $request->get_body(); |
| 722 | |
| 723 | if ( empty( $raw_body ) ) { |
| 724 | return new WP_REST_Response( [ |
| 725 | 'jsonrpc' => '2.0', |
| 726 | 'id' => null, |
| 727 | 'error' => [ 'code' => -32700, 'message' => 'Parse error: empty body' ] |
| 728 | ], 400 ); |
| 729 | } |
| 730 | |
| 731 | $data = json_decode( $raw_body, true ); |
| 732 | |
| 733 | if ( json_last_error() !== JSON_ERROR_NONE ) { |
| 734 | return new WP_REST_Response( [ |
| 735 | 'jsonrpc' => '2.0', |
| 736 | 'id' => null, |
| 737 | 'error' => [ 'code' => -32700, 'message' => 'Parse error: invalid JSON' ] |
| 738 | ], 400 ); |
| 739 | } |
| 740 | |
| 741 | // Log the request if debugging is enabled |
| 742 | if ( $this->logging && isset( $data['method'] ) ) { |
| 743 | error_log( '[AI Engine MCP HTTP] ↓ ' . $data['method'] ); |
| 744 | } |
| 745 | |
| 746 | // Reuse the existing direct JSON-RPC handler |
| 747 | return $this->handle_direct_jsonrpc( $request, $data ); |
| 748 | } |
| 749 | |
| 750 | /** |
| 751 | * Handle GET requests for Streamable HTTP. |
| 752 | * This opens an SSE stream for server-to-client messages. |
| 753 | * Used when the server needs to send notifications or progress updates. |
| 754 | */ |
| 755 | private function handle_streamable_http_get( WP_REST_Request $request ) { |
| 756 | // Check Accept header - must accept text/event-stream |
| 757 | $accept = $request->get_header( 'accept' ); |
| 758 | if ( strpos( $accept, 'text/event-stream' ) === false ) { |
| 759 | return new WP_REST_Response( [ |
| 760 | 'error' => 'Accept header must include text/event-stream' |
| 761 | ], 406 ); |
| 762 | } |
| 763 | |
| 764 | // Get or create session ID |
| 765 | $session_header = $request->get_header( 'mcp-session-id' ); |
| 766 | $session_id = !empty( $session_header ) ? sanitize_text_field( $session_header ) : wp_generate_uuid4(); |
| 767 | |
| 768 | if ( $this->logging ) { |
| 769 | error_log( '[AI Engine MCP HTTP] 📡 SSE stream opened for session: ' . substr( $session_id, 0, 8 ) . '...' ); |
| 770 | } |
| 771 | |
| 772 | // Set up SSE output |
| 773 | @ini_set( 'zlib.output_compression', '0' ); |
| 774 | @ini_set( 'output_buffering', '0' ); |
| 775 | @ini_set( 'implicit_flush', '1' ); |
| 776 | if ( function_exists( 'ob_implicit_flush' ) ) { |
| 777 | ob_implicit_flush( true ); |
| 778 | } |
| 779 | |
| 780 | header( 'Content-Type: text/event-stream' ); |
| 781 | header( 'Cache-Control: no-cache' ); |
| 782 | header( 'X-Accel-Buffering: no' ); |
| 783 | header( 'Connection: keep-alive' ); |
| 784 | header( 'Mcp-Session-Id: ' . $session_id ); |
| 785 | |
| 786 | while ( ob_get_level() ) { |
| 787 | ob_end_flush(); |
| 788 | } |
| 789 | |
| 790 | $this->session_id = $session_id; |
| 791 | $this->last_action_time = time(); |
| 792 | |
| 793 | // Send initial connection event |
| 794 | echo "event: open\n"; |
| 795 | echo 'data: {"session":"' . esc_js( $session_id ) . "\"}\n\n"; |
| 796 | flush(); |
| 797 | |
| 798 | // Main SSE loop - listen for server-initiated messages |
| 799 | while ( true ) { |
| 800 | $max_time = $this->logging ? 30 : 60 * 3; |
| 801 | $idle = ( time() - $this->last_action_time ) >= $max_time; |
| 802 | |
| 803 | if ( connection_aborted() || $idle ) { |
| 804 | if ( $this->logging ) { |
| 805 | error_log( '[AI Engine MCP HTTP] 🔚 SSE closed (' . ( $idle ? 'idle' : 'abort' ) . ')' ); |
| 806 | } |
| 807 | break; |
| 808 | } |
| 809 | |
| 810 | // Check for queued messages |
| 811 | foreach ( $this->fetch_messages( $session_id ) as $msg ) { |
| 812 | if ( isset( $msg['method'] ) && $msg['method'] === 'mwai/kill' ) { |
| 813 | echo "event: close\ndata: {}\n\n"; |
| 814 | flush(); |
| 815 | exit; |
| 816 | } |
| 817 | |
| 818 | echo "event: message\n"; |
| 819 | echo 'data: ' . wp_json_encode( $msg, JSON_UNESCAPED_UNICODE ) . "\n\n"; |
| 820 | flush(); |
| 821 | $this->last_action_time = time(); |
| 822 | } |
| 823 | |
| 824 | // Heartbeat every 10 seconds |
| 825 | $time_since_last = time() - $this->last_action_time; |
| 826 | if ( $time_since_last >= 10 && $time_since_last % 10 === 0 ) { |
| 827 | echo ": heartbeat\n\n"; |
| 828 | flush(); |
| 829 | } |
| 830 | |
| 831 | usleep( 200000 ); // 200ms |
| 832 | } |
| 833 | |
| 834 | exit; |
| 835 | } |
| 836 | |
| 837 | /** |
| 838 | * Handle DELETE requests for Streamable HTTP. |
| 839 | * This terminates the session and cleans up any resources. |
| 840 | */ |
| 841 | private function handle_streamable_http_delete( WP_REST_Request $request ) { |
| 842 | $session_header = $request->get_header( 'mcp-session-id' ); |
| 843 | |
| 844 | if ( empty( $session_header ) ) { |
| 845 | return new WP_REST_Response( [ |
| 846 | 'error' => 'Mcp-Session-Id header required' |
| 847 | ], 400 ); |
| 848 | } |
| 849 | |
| 850 | $session_id = sanitize_text_field( $session_header ); |
| 851 | |
| 852 | if ( $this->logging ) { |
| 853 | error_log( '[AI Engine MCP HTTP] 🗑️ Session terminated: ' . substr( $session_id, 0, 8 ) . '...' ); |
| 854 | } |
| 855 | |
| 856 | // Queue kill signal for any active SSE streams |
| 857 | $this->store_message( $session_id, [ |
| 858 | 'jsonrpc' => '2.0', |
| 859 | 'method' => 'mwai/kill' |
| 860 | ] ); |
| 861 | |
| 862 | // Clean up any remaining transients for this session |
| 863 | global $wpdb; |
| 864 | $like = $wpdb->esc_like( '_transient_' . "{$this->queue_key}_{$session_id}_" ) . '%'; |
| 865 | $wpdb->query( |
| 866 | $wpdb->prepare( |
| 867 | "DELETE FROM {$wpdb->options} WHERE option_name LIKE %s", |
| 868 | $like |
| 869 | ) |
| 870 | ); |
| 871 | |
| 872 | // Return 204 No Content on successful termination |
| 873 | return new WP_REST_Response( null, 204 ); |
| 874 | } |
| 875 | #endregion |
| 876 | |
| 877 | #region Handle /messages (JSON-RPC ingress) |
| 878 | public function handle_message( WP_REST_Request $request ) { |
| 879 | $sess = sanitize_text_field( $request->get_param( 'session_id' ) ); |
| 880 | $raw = $request->get_body(); |
| 881 | $dat = json_decode( $raw, true ); |
| 882 | |
| 883 | // Only log important methods in detail |
| 884 | if ( $this->logging && $dat && isset( $dat['method'] ) ) { |
| 885 | $method = $dat['method']; |
| 886 | // Skip logging for repetitive/less important notifications |
| 887 | if ( !in_array( $method, ['notifications/initialized', 'notifications/cancelled'] ) ) { |
| 888 | error_log( '[AI Engine MCP] ↓ ' . $method ); |
| 889 | } |
| 890 | } |
| 891 | |
| 892 | if ( json_last_error() !== JSON_ERROR_NONE ) { |
| 893 | $this->queue_error( $sess, null, -32700, 'Parse error: invalid JSON' ); |
| 894 | return new WP_REST_Response( null, 204 ); |
| 895 | } |
| 896 | if ( !is_array( $dat ) ) { |
| 897 | $this->queue_error( $sess, null, -32600, 'Invalid Request' ); |
| 898 | return new WP_REST_Response( null, 204 ); |
| 899 | } |
| 900 | |
| 901 | $id = $dat['id'] ?? null; |
| 902 | $method = $dat['method'] ?? null; |
| 903 | |
| 904 | /* — notifications —*/ |
| 905 | if ( $method === 'initialized' ) { |
| 906 | return new WP_REST_Response( null, 204 ); |
| 907 | } |
| 908 | if ( $method === 'notifications/cancelled' ) { |
| 909 | // Agent finished - queue kill signal to close SSE immediately |
| 910 | if ( $this->logging ) { |
| 911 | error_log( '[AI Engine MCP] Agent cancelled - closing SSE connection' ); |
| 912 | } |
| 913 | $this->store_message( $sess, [ |
| 914 | 'jsonrpc' => '2.0', |
| 915 | 'method' => 'mwai/kill' |
| 916 | ] ); |
| 917 | return new WP_REST_Response( null, 204 ); |
| 918 | } |
| 919 | if ( $method === 'mwai/kill' ) { |
| 920 | // Kill signal received - no need for verbose logging |
| 921 | // Queue the kill message for SSE to pick up before exiting |
| 922 | $this->store_message( $sess, [ |
| 923 | 'jsonrpc' => '2.0', |
| 924 | 'method' => 'mwai/kill' |
| 925 | ] ); |
| 926 | // Give it a moment to be stored |
| 927 | usleep( 100000 ); // 100ms |
| 928 | return new WP_REST_Response( null, 204 ); |
| 929 | } |
| 930 | |
| 931 | // It's a notification, no ID = no reply |
| 932 | if ( $id === null && $method !== null ) { |
| 933 | return new WP_REST_Response( null, 204 ); |
| 934 | } |
| 935 | |
| 936 | if ( !$method ) { |
| 937 | $this->queue_error( $sess, $id, -32600, 'Invalid Request: method missing' ); |
| 938 | return new WP_REST_Response( null, 204 ); |
| 939 | } |
| 940 | |
| 941 | try { |
| 942 | |
| 943 | $reply = null; |
| 944 | |
| 945 | #region Methods switch |
| 946 | switch ( $method ) { |
| 947 | |
| 948 | case 'initialize': |
| 949 | // Check if client requests a specific protocol version |
| 950 | $params = $dat['params'] ?? []; |
| 951 | $requested_version = $params['protocolVersion'] ?? null; |
| 952 | $client_info = $params['clientInfo'] ?? null; |
| 953 | |
| 954 | if ( $this->logging && $client_info ) { |
| 955 | $client_name = $client_info['name'] ?? 'unknown'; |
| 956 | $client_version = $client_info['version'] ?? 'unknown'; |
| 957 | error_log( "[AI Engine MCP] Client: {$client_name} v{$client_version}" ); |
| 958 | } |
| 959 | |
| 960 | if ( $requested_version && $requested_version !== $this->protocol_version ) { |
| 961 | if ( $this->logging ) { |
| 962 | Meow_MWAI_Logging::warn( "[AI Engine MCP] Client requested protocol version {$requested_version}, but we only support {$this->protocol_version}" ); |
| 963 | } |
| 964 | } |
| 965 | |
| 966 | $reply = [ |
| 967 | 'jsonrpc' => '2.0', |
| 968 | 'id' => $id, |
| 969 | 'result' => [ |
| 970 | 'protocolVersion' => $this->protocol_version, |
| 971 | 'serverInfo' => (object) [ |
| 972 | 'name' => 'AI Engine - ' . get_bloginfo( 'name' ), |
| 973 | 'version' => $this->server_version, |
| 974 | ], |
| 975 | 'capabilities' => (object) [ |
| 976 | 'tools' => new stdClass(), // Empty object, matching official SDK |
| 977 | ], |
| 978 | ], |
| 979 | ]; |
| 980 | break; |
| 981 | |
| 982 | case 'tools/list': |
| 983 | $tools = $this->get_tools_list(); |
| 984 | |
| 985 | // Debug logging for tools/list |
| 986 | if ( $this->logging ) { |
| 987 | $user_agent = isset( $_SERVER['HTTP_USER_AGENT'] ) ? $_SERVER['HTTP_USER_AGENT'] : 'unknown'; |
| 988 | error_log( '[AI Engine MCP] 📋 tools/list requested by: ' . $user_agent ); |
| 989 | error_log( '[AI Engine MCP] 📊 Returning ' . count( $tools ) . ' tools' ); |
| 990 | if ( count( $tools ) > 0 ) { |
| 991 | $tool_names = array_column( $tools, 'name' ); |
| 992 | error_log( '[AI Engine MCP] 🛠️ Tool names: ' . implode( ', ', $tool_names ) ); |
| 993 | } |
| 994 | else { |
| 995 | error_log( '[AI Engine MCP] ⚠️ WARNING: No tools returned!' ); |
| 996 | } |
| 997 | } |
| 998 | |
| 999 | $reply = [ |
| 1000 | 'jsonrpc' => '2.0', |
| 1001 | 'id' => $id, |
| 1002 | 'result' => [ 'tools' => $tools ], |
| 1003 | ]; |
| 1004 | break; |
| 1005 | |
| 1006 | case 'resources/list': |
| 1007 | $reply = [ |
| 1008 | 'jsonrpc' => '2.0', |
| 1009 | 'id' => $id, |
| 1010 | 'result' => [ 'resources' => $this->get_resources_list() ], |
| 1011 | ]; |
| 1012 | break; |
| 1013 | |
| 1014 | case 'prompts/list': |
| 1015 | $reply = [ |
| 1016 | 'jsonrpc' => '2.0', |
| 1017 | 'id' => $id, |
| 1018 | 'result' => [ 'prompts' => $this->get_prompts_list() ], |
| 1019 | ]; |
| 1020 | break; |
| 1021 | |
| 1022 | case 'tools/call': |
| 1023 | $params = $dat['params'] ?? []; |
| 1024 | $tool = $params['name'] ?? ''; |
| 1025 | $arguments = $params['arguments'] ?? []; |
| 1026 | |
| 1027 | if ( $this->logging ) { |
| 1028 | error_log( '[AI Engine MCP SSE] 🔧 tools/call - Tool: ' . $tool ); |
| 1029 | error_log( '[AI Engine MCP SSE] 🔧 tools/call - Arguments: ' . wp_json_encode( $arguments ) ); |
| 1030 | } |
| 1031 | |
| 1032 | try { |
| 1033 | $reply = $this->execute_tool( $tool, $arguments, $id ); |
| 1034 | if ( $this->logging ) { |
| 1035 | error_log( '[AI Engine MCP SSE] � |
| 1036 | tools/call - Success for tool: ' . $tool ); |
| 1037 | } |
| 1038 | } |
| 1039 | catch ( Exception $e ) { |
| 1040 | if ( $this->logging ) { |
| 1041 | error_log( '[AI Engine MCP SSE] ❌ tools/call - Error: ' . $e->getMessage() ); |
| 1042 | } |
| 1043 | throw $e; |
| 1044 | } |
| 1045 | break; |
| 1046 | |
| 1047 | default: |
| 1048 | $reply = $this->rpc_error( $id, -32601, "Method not found: {$method}" ); |
| 1049 | } |
| 1050 | #endregion |
| 1051 | |
| 1052 | if ( $reply ) { |
| 1053 | // Don't log response queuing - it's too noisy |
| 1054 | $this->store_message( $sess, $reply ); |
| 1055 | } |
| 1056 | |
| 1057 | } |
| 1058 | catch ( Exception $e ) { |
| 1059 | $this->queue_error( $sess, $id, -32603, 'Internal error', $e->getMessage() ); |
| 1060 | } |
| 1061 | |
| 1062 | return new WP_REST_Response( null, 204 ); |
| 1063 | } |
| 1064 | #endregion |
| 1065 | |
| 1066 | #region Tools Definitions |
| 1067 | private function get_tools_list() { |
| 1068 | $base_tools = [ |
| 1069 | [ |
| 1070 | 'name' => 'mcp_ping', |
| 1071 | 'description' => 'Simple connectivity check. Returns the current GMT time and the WordPress site name. Whenever a tool call fails (error or timeout), immediately invoke mcp_ping to verify the server; if mcp_ping itself does not respond, assume the server is temporarily unreachable and pause additional tool calls.', |
| 1072 | 'inputSchema' => [ |
| 1073 | 'type' => 'object', |
| 1074 | 'properties' => (object) [], |
| 1075 | 'required' => [] |
| 1076 | ], |
| 1077 | 'annotations' => [ |
| 1078 | 'readOnlyHint' => true, |
| 1079 | 'destructiveHint' => false, |
| 1080 | 'openWorldHint' => false, |
| 1081 | ], |
| 1082 | ], |
| 1083 | ]; |
| 1084 | |
| 1085 | if ( $this->logging ) { |
| 1086 | error_log( '[AI Engine MCP] 🔧 get_tools_list() - Starting with ' . count( $base_tools ) . ' base tools' ); |
| 1087 | } |
| 1088 | |
| 1089 | $filtered_tools = apply_filters( 'mwai_mcp_tools', $base_tools ); |
| 1090 | |
| 1091 | if ( $this->logging ) { |
| 1092 | error_log( '[AI Engine MCP] 🔧 get_tools_list() - After filters: ' . count( $filtered_tools ) . ' tools' ); |
| 1093 | } |
| 1094 | |
| 1095 | $normalized_tools = []; |
| 1096 | foreach ( $filtered_tools as $tool_index => $tool_definition ) { |
| 1097 | $normalized = $this->normalize_tool_definition( $tool_definition, $tool_index ); |
| 1098 | if ( $normalized ) { |
| 1099 | $normalized_tools[] = $normalized; |
| 1100 | } |
| 1101 | } |
| 1102 | |
| 1103 | if ( $this->logging ) { |
| 1104 | error_log( '[AI Engine MCP] 🔧 get_tools_list() - Normalized tools: ' . count( $normalized_tools ) ); |
| 1105 | } |
| 1106 | |
| 1107 | return $normalized_tools; |
| 1108 | } |
| 1109 | #endregion |
| 1110 | |
| 1111 | #region Resources Definitions |
| 1112 | private function get_resources_list() { |
| 1113 | return []; |
| 1114 | } |
| 1115 | #endregion |
| 1116 | |
| 1117 | #region Prompts Definitions |
| 1118 | private function get_prompts_list() { |
| 1119 | return []; |
| 1120 | } |
| 1121 | #endregion |
| 1122 | |
| 1123 | #region Tool Normalization Helpers |
| 1124 | private function normalize_tool_definition( $tool, $index ) { |
| 1125 | if ( !is_array( $tool ) ) { |
| 1126 | if ( $this->logging ) { |
| 1127 | error_log( '[AI Engine MCP] ⚠️ Tool definition at index ' . $index . ' skipped (expected array).' ); |
| 1128 | } |
| 1129 | return null; |
| 1130 | } |
| 1131 | |
| 1132 | $name = isset( $tool['name'] ) ? trim( (string) $tool['name'] ) : ''; |
| 1133 | if ( $name === '' ) { |
| 1134 | if ( $this->logging ) { |
| 1135 | error_log( '[AI Engine MCP] ⚠️ Tool skipped due to missing name at index ' . $index ); |
| 1136 | } |
| 1137 | return null; |
| 1138 | } |
| 1139 | |
| 1140 | $normalized_schema = $this->normalize_input_schema( $tool['inputSchema'] ?? null, $name ); |
| 1141 | if ( !$normalized_schema ) { |
| 1142 | if ( $this->logging ) { |
| 1143 | error_log( '[AI Engine MCP] ⚠️ Tool "' . $name . '" skipped due to invalid input schema.' ); |
| 1144 | } |
| 1145 | return null; |
| 1146 | } |
| 1147 | |
| 1148 | $normalized = [ |
| 1149 | 'name' => $name, |
| 1150 | 'inputSchema' => $normalized_schema, |
| 1151 | ]; |
| 1152 | |
| 1153 | if ( isset( $tool['description'] ) && $tool['description'] !== '' ) { |
| 1154 | $normalized['description'] = wp_strip_all_tags( (string) $tool['description'] ); |
| 1155 | } |
| 1156 | |
| 1157 | if ( isset( $tool['annotations'] ) && is_array( $tool['annotations'] ) ) { |
| 1158 | $annotations = $this->normalize_annotations( $tool['annotations'], $name ); |
| 1159 | if ( !empty( $annotations ) ) { |
| 1160 | $normalized['annotations'] = $annotations; |
| 1161 | } |
| 1162 | } |
| 1163 | |
| 1164 | if ( isset( $tool['category'] ) ) { |
| 1165 | $normalized['annotations'] = $normalized['annotations'] ?? []; |
| 1166 | if ( empty( $normalized['annotations']['title'] ) ) { |
| 1167 | $normalized['annotations']['title'] = wp_strip_all_tags( (string) $tool['category'] ); |
| 1168 | } |
| 1169 | } |
| 1170 | |
| 1171 | return $normalized; |
| 1172 | } |
| 1173 | |
| 1174 | private function normalize_input_schema( $schema, string $tool_name ) { |
| 1175 | if ( !is_array( $schema ) ) { |
| 1176 | return null; |
| 1177 | } |
| 1178 | |
| 1179 | $type = isset( $schema['type'] ) ? (string) $schema['type'] : 'object'; |
| 1180 | if ( $type !== 'object' ) { |
| 1181 | if ( $this->logging ) { |
| 1182 | error_log( '[AI Engine MCP] ⚠️ Tool "' . $tool_name . '" has unsupported schema type: ' . $type ); |
| 1183 | } |
| 1184 | return null; |
| 1185 | } |
| 1186 | |
| 1187 | $properties = []; |
| 1188 | if ( isset( $schema['properties'] ) && ( is_array( $schema['properties'] ) || is_object( $schema['properties'] ) ) ) { |
| 1189 | foreach ( (array) $schema['properties'] as $prop_name => $definition ) { |
| 1190 | if ( !is_array( $definition ) ) { |
| 1191 | $definition = []; |
| 1192 | } |
| 1193 | |
| 1194 | if ( isset( $definition['type'] ) ) { |
| 1195 | // Validate type definition |
| 1196 | if ( is_array( $definition['type'] ) ) { |
| 1197 | // Array of types (union types) - validate they're compatible with MCP clients |
| 1198 | $type_array = array_map( 'strval', $definition['type'] ); |
| 1199 | |
| 1200 | // Check for complex types that need additional schema details |
| 1201 | $complex_types = array_intersect( $type_array, [ 'object', 'array' ] ); |
| 1202 | if ( !empty( $complex_types ) ) { |
| 1203 | if ( $this->logging ) { |
| 1204 | error_log( |
| 1205 | '[AI Engine MCP] ⚠️ Tool "' . $tool_name . '" property "' . $prop_name . |
| 1206 | '" has problematic union type with complex types: [' . implode( ', ', $type_array ) . |
| 1207 | ']. This breaks ChatGPT. Auto-fixing by removing type constraint.' |
| 1208 | ); |
| 1209 | } |
| 1210 | // Auto-fix: Remove the type constraint to accept any value |
| 1211 | unset( $definition['type'] ); |
| 1212 | // Keep description if present, or add one |
| 1213 | if ( !isset( $definition['description'] ) ) { |
| 1214 | $definition['description'] = 'Value can be of any type'; |
| 1215 | } |
| 1216 | } |
| 1217 | else { |
| 1218 | $definition['type'] = $type_array; |
| 1219 | } |
| 1220 | } |
| 1221 | else { |
| 1222 | $definition['type'] = (string) $definition['type']; |
| 1223 | } |
| 1224 | } |
| 1225 | |
| 1226 | $properties[ $prop_name ] = $definition; |
| 1227 | } |
| 1228 | } |
| 1229 | |
| 1230 | $required = []; |
| 1231 | if ( isset( $schema['required'] ) && is_array( $schema['required'] ) ) { |
| 1232 | foreach ( $schema['required'] as $field ) { |
| 1233 | $field_name = trim( (string) $field ); |
| 1234 | if ( $field_name !== '' ) { |
| 1235 | $required[] = $field_name; |
| 1236 | } |
| 1237 | } |
| 1238 | $required = array_values( array_unique( $required ) ); |
| 1239 | } |
| 1240 | |
| 1241 | $normalized = [ |
| 1242 | 'type' => 'object', |
| 1243 | 'properties' => empty( $properties ) ? new stdClass() : $properties, |
| 1244 | ]; |
| 1245 | |
| 1246 | if ( !empty( $required ) ) { |
| 1247 | $normalized['required'] = $required; |
| 1248 | } |
| 1249 | |
| 1250 | if ( array_key_exists( 'additionalProperties', $schema ) ) { |
| 1251 | $normalized['additionalProperties'] = (bool) $schema['additionalProperties']; |
| 1252 | } |
| 1253 | |
| 1254 | return $normalized; |
| 1255 | } |
| 1256 | |
| 1257 | private function normalize_annotations( array $annotations, string $tool_name ): array { |
| 1258 | $allowed_keys = [ 'title', 'readOnlyHint', 'destructiveHint', 'idempotentHint', 'openWorldHint' ]; |
| 1259 | $normalized = []; |
| 1260 | |
| 1261 | foreach ( $annotations as $key => $value ) { |
| 1262 | if ( !in_array( $key, $allowed_keys, true ) ) { |
| 1263 | continue; |
| 1264 | } |
| 1265 | |
| 1266 | if ( in_array( $key, [ 'readOnlyHint', 'destructiveHint', 'idempotentHint', 'openWorldHint' ], true ) ) { |
| 1267 | $normalized[ $key ] = (bool) $value; |
| 1268 | } |
| 1269 | elseif ( $key === 'title' ) { |
| 1270 | $normalized['title'] = wp_strip_all_tags( (string) $value ); |
| 1271 | } |
| 1272 | } |
| 1273 | |
| 1274 | if ( empty( $normalized ) && $this->logging && !empty( $annotations ) ) { |
| 1275 | error_log( '[AI Engine MCP] 🔎 Tool "' . $tool_name . '" included unsupported annotation keys.' ); |
| 1276 | } |
| 1277 | |
| 1278 | return $normalized; |
| 1279 | } |
| 1280 | #endregion |
| 1281 | |
| 1282 | #region Tools Call (execute_tool) |
| 1283 | private function execute_tool( $tool, $args, $id ) { |
| 1284 | try { |
| 1285 | // Handle built-in tools first |
| 1286 | if ( $tool === 'mcp_ping' ) { |
| 1287 | if ( $this->logging ) { |
| 1288 | $this->log( '🛠️ Tool: mcp_ping' ); |
| 1289 | } |
| 1290 | $ping_data = [ |
| 1291 | 'time' => gmdate( 'Y-m-d H:i:s' ), |
| 1292 | 'name' => get_bloginfo( 'name' ), |
| 1293 | ]; |
| 1294 | return [ |
| 1295 | 'jsonrpc' => '2.0', |
| 1296 | 'id' => $id, |
| 1297 | 'result' => [ |
| 1298 | 'content' => [ |
| 1299 | [ |
| 1300 | 'type' => 'text', |
| 1301 | 'text' => 'Ping successful: ' . wp_json_encode( $ping_data, JSON_PRETTY_PRINT ), |
| 1302 | ], |
| 1303 | ], |
| 1304 | 'data' => $ping_data, |
| 1305 | ], |
| 1306 | ]; |
| 1307 | } |
| 1308 | |
| 1309 | // Let other modules handle their tools |
| 1310 | if ( $this->logging ) { |
| 1311 | // Log tool calls with more context |
| 1312 | $args_preview = ''; |
| 1313 | if ( !empty( $args ) ) { |
| 1314 | // Show key args for common tools |
| 1315 | if ( isset( $args['ID'] ) ) { |
| 1316 | $args_preview = ' (ID: ' . $args['ID'] . ')'; |
| 1317 | } |
| 1318 | elseif ( isset( $args['query'] ) ) { |
| 1319 | $args_preview = ' (query: "' . substr( $args['query'], 0, 30 ) . '...")'; |
| 1320 | } |
| 1321 | elseif ( isset( $args['message'] ) ) { |
| 1322 | $args_preview = ' (message: "' . substr( $args['message'], 0, 30 ) . '...")'; |
| 1323 | } |
| 1324 | } |
| 1325 | // Log to both error log and UI |
| 1326 | error_log( '[AI Engine MCP] 🛠️ ' . $tool . $args_preview ); |
| 1327 | $this->log( '🛠️ Tool: ' . $tool . $args_preview ); |
| 1328 | } |
| 1329 | $filtered = apply_filters( 'mwai_mcp_callback', null, $tool, $args, $id, $this ); |
| 1330 | |
| 1331 | if ( $filtered !== null ) { |
| 1332 | // Check if it's already a full JSON-RPC response (backward compatibility) |
| 1333 | if ( is_array( $filtered ) && isset( $filtered['jsonrpc'] ) && isset( $filtered['id'] ) ) { |
| 1334 | return $filtered; |
| 1335 | } |
| 1336 | |
| 1337 | // Otherwise, wrap the result in proper JSON-RPC format |
| 1338 | return [ |
| 1339 | 'jsonrpc' => '2.0', |
| 1340 | 'id' => $id, |
| 1341 | 'result' => $this->format_tool_result( $filtered ), |
| 1342 | ]; |
| 1343 | } |
| 1344 | |
| 1345 | throw new Exception( "Unknown tool: {$tool}" ); |
| 1346 | } |
| 1347 | catch ( Exception $e ) { |
| 1348 | return $this->rpc_error( $id, -32603, $e->getMessage() ); |
| 1349 | } |
| 1350 | } |
| 1351 | #endregion |
| 1352 | |
| 1353 | #region Message Queue (per-message transient) |
| 1354 | private function transient_key( $sess, $id ) { |
| 1355 | return "{$this->queue_key}_{$sess}_{$id}"; |
| 1356 | } |
| 1357 | |
| 1358 | private function store_message( $sess, $payload ) { |
| 1359 | if ( !$sess ) { |
| 1360 | return; |
| 1361 | } |
| 1362 | $idKey = array_key_exists( 'id', $payload ) ? ( $payload['id'] ?? 'NULL' ) : 'N/A'; |
| 1363 | set_transient( $this->transient_key( $sess, $idKey ), $payload, 30 ); |
| 1364 | $this->log( "queued #{$idKey}" ); |
| 1365 | } |
| 1366 | |
| 1367 | private function fetch_messages( $sess ) { |
| 1368 | global $wpdb; |
| 1369 | $like = $wpdb->esc_like( '_transient_' . "{$this->queue_key}_{$sess}_" ) . '%'; |
| 1370 | |
| 1371 | $rows = $wpdb->get_results( |
| 1372 | $wpdb->prepare( |
| 1373 | "SELECT option_name, option_value FROM {$wpdb->options} WHERE option_name LIKE %s", |
| 1374 | $like |
| 1375 | ), |
| 1376 | ARRAY_A |
| 1377 | ); |
| 1378 | |
| 1379 | $msgs = []; |
| 1380 | foreach ( $rows as $r ) { |
| 1381 | $msgs[] = maybe_unserialize( $r['option_value'] ); |
| 1382 | delete_option( $r['option_name'] ); |
| 1383 | } |
| 1384 | usort( $msgs, fn ( $a, $b ) => ( $a['id'] ?? 0 ) <=> ( $b['id'] ?? 0 ) ); |
| 1385 | if ( $msgs ) { |
| 1386 | $this->log( 'flush ' . count( $msgs ) . ' msg(s)' ); |
| 1387 | } |
| 1388 | return $msgs; |
| 1389 | } |
| 1390 | #endregion |
| 1391 | |
| 1392 | #region Resources (note) |
| 1393 | /*--------------------------------------------------*/ |
| 1394 | /** |
| 1395 | * MCP also supports “resources” – static or dynamic data a client can |
| 1396 | * retrieve by URL (e.g. `mcp://resource/posts/123`). |
| 1397 | */ |
| 1398 | #endregion |
| 1399 | } |
| 1400 |