WP Navigator MCP

/** * AI Agent Detection * * Detects which AI agent is running this MCP server and provides * agent identification headers for WordPress actor attribution. * * @package WP_Navigator_MCP * @since 1.2.0 */ import * as crypto from 'crypto'; import * as fs from 'fs'; import * as path from 'path'; import * as os from 'os'; /** * Detect which AI agent is running this MCP server * * @returns Agent slug (e.g., 'claude-code', 'codex', 'gemini-cli', 'mcp-client') */ export function detectAgent(): string { // Check environment variables if (process.env.CLAUDE_CODE_SESSION) return 'claude-code'; if (process.env.CODEX_SESSION) return 'codex'; if (process.env.GEMINI_CLI_SESSION) return 'gemini-cli'; // Check process.title (set by CLI tools) const title = process.title?.toLowerCase() || ''; if (title.includes('claude')) return 'claude-code'; if (title.includes('codex')) return 'codex'; if (title.includes('gemini')) return 'gemini-cli'; // Check parent process name (macOS/Linux only) // This is a best-effort detection and may not work in all environments try { const ppid = process.ppid; // Could inspect parent process via ps command // (omitted for brevity - would exec `ps -p ${ppid} -o comm=`) } catch (e) { // Fallback } // Generic MCP client return 'mcp-client'; } /** * Get human-readable agent name * * @returns Human-readable agent name with model info */ export function getAgentName(): string { const agent = detectAgent(); const modelInfo = detectModelInfo(); const names: Record<string, string> = { 'claude-code': `Claude Code (${modelInfo})`, 'codex': `Codex (${modelInfo})`, 'gemini-cli': `Gemini CLI (${modelInfo})`, 'mcp-client': 'Generic MCP Client', }; return names[agent] || 'Unknown Agent'; } /** * Detect AI model info from environment * * @returns AI model name or 'Unknown' */ function detectModelInfo(): string { // Claude Desktop / Claude Code sets these if (process.env.ANTHROPIC_MODEL) return process.env.ANTHROPIC_MODEL; // Codex / OpenAI CLI if (process.env.OPENAI_MODEL) return process.env.OPENAI_MODEL; // Gemini if (process.env.GEMINI_MODEL) return process.env.GEMINI_MODEL; // Fallback: infer from agent const agent = detectAgent(); if (agent === 'claude-code') return 'Sonnet 4'; if (agent === 'codex') return 'GPT-5'; if (agent === 'gemini-cli') return 'Gemini 2.0 Flash'; return 'Unknown'; } /** * Get or create persistent session UUID * * Session ID is stored in ~/.wpnav-session-id and persists across * MCP server restarts to correlate operations within the same AI session. * * @returns Session UUID v4 */ export function getOrCreateSessionId(): string { const sessionFile = path.join(os.homedir(), '.wpnav-session-id'); try { if (fs.existsSync(sessionFile)) { const sessionId = fs.readFileSync(sessionFile, 'utf-8').trim(); if (sessionId && sessionId.length === 36) { return sessionId; } } } catch (e) { // File doesn't exist or not readable } // Generate new UUID v4 const uuid = crypto.randomUUID(); try { fs.writeFileSync(sessionFile, uuid, 'utf-8'); } catch (e) { // Can't persist, just use in-memory UUID } return uuid; } /** * Generate HMAC signature for request * * Implements Stripe-style HMAC-SHA256 signature validation: * - Canonical string: {METHOD}\n{PATH}\n{TIMESTAMP}\n{BODY_SHA256} * - Signature: Base64(HMAC-SHA256(secret, canonical)) * * @param method HTTP method (GET, POST, etc.) * @param url Full URL (will extract path) * @param timestamp ISO 8601 timestamp * @param body Request body (or empty string) * @param secret Shared secret * @returns Base64-encoded HMAC signature */ export function generateHmacSignature( method: string, url: string, timestamp: string, body: string, secret: string ): string { // Parse URL to get path only const urlObj = new URL(url); const urlPath = urlObj.pathname + urlObj.search; // Compute body hash const bodyHash = crypto.createHash('sha256').update(body || '').digest('hex'); // Build canonical string const canonical = `${method}\n${urlPath}\n${timestamp}\n${bodyHash}`; // Compute HMAC const hmac = crypto.createHmac('sha256', secret).update(canonical).digest('base64'); return hmac; } /** * Get AI agent headers for WordPress requests * * @param config Optional config with HMAC signing options * @returns Headers object */ export function getAgentHeaders(config?: { method?: string; url?: string; body?: string; signHeaders?: boolean; hmacSecret?: string; }): Record<string, string> { const agent = detectAgent(); const agentName = getAgentName(); const sessionId = getOrCreateSessionId(); const timestamp = new Date().toISOString(); const headers: Record<string, string> = { 'User-Agent': `WP-Navigator-MCP/1.0.0 (${agent})`, 'X-WP-Navigator-Client': 'wp-navigator', 'X-WP-Navigator-Version': '1.0.0', 'X-WP-Navigator-Agent': agent, 'X-WP-Navigator-Agent-Name': agentName, 'X-WP-Navigator-Session': sessionId, 'X-WP-Navigator-Timestamp': timestamp, }; // Add model info if available const modelInfo = detectModelInfo(); if (modelInfo !== 'Unknown') { headers['X-WP-Navigator-Model'] = modelInfo; } // Add HMAC signature if requested if (config?.signHeaders && config?.hmacSecret && config?.method && config?.url) { const signature = generateHmacSignature( config.method, config.url, timestamp, config.body || '', config.hmacSecret ); headers['X-WP-Navigator-Signature'] = signature; } return headers; }