AgentNDX — MCP Server Directory

# AgentNDX > A curated registry for the agentic web. Find, search, and connect to MCP servers, A2A agents, and x402-enabled services. AgentNDX indexes tools that AI agents can connect to and use. If you're an agent looking for a capability, search here. If you're a developer with a tool to list, submit at /submit. ## What This Is AgentNDX is a curated directory of 137+ Model Context Protocol (MCP) servers, A2A agents, and x402-payable services. Every entry is verified, schema-normalized, and machine-readable. Agents can search the directory via our own MCP endpoint and pay per search via x402 micropayments — no API key required. ## Base URL https://agentndx.ai ## Machine-Readable Endpoints (Free) - GET /api/servers.json — Full server index (JSON, all 137+ entries) - GET /api/categories.json — All categories with counts - GET /api/stats.json — Registry statistics (total, MCP, A2A, x402, verified counts) ## MCP Endpoint The AgentNDX directory is itself an MCP server. Agents can call it to discover other agents. - **URL:** https://agentndx.ai/mcp - **Transport:** Streamable HTTP (MCP spec 2025-03-26) - **Payment:** x402 on Base mainnet — $0.005 USDC per search (search tool only) - **Auth:** None — x402 handles authorization at call time - **Free tools:** get_server_details, list_categories, get_stats ### Add to Claude Code ``` claude mcp add agentndx https://agentndx.ai/mcp ``` ### Add to Claude Desktop (claude_desktop_config.json) ```json { "mcpServers": { "agentndx": { "url": "https://agentndx.ai/mcp" } } } ``` ## Tools ### search_mcp_servers Search 137+ servers by keyword, category, or capability. Costs $0.005 USDC via x402. Parameters: - `query` (string) — e.g. "vector database", "send email", "browser automation" - `category` (string, optional) — communication | data | web | code | ai | payments | identity | productivity | infrastructure | media - `limit` (number, optional) — default 10 ### get_server_details Ge

{ "openapi": "3.1.0", "info": { "title": "AgentNDX API", "description": "Network registry for the agentic web. MCP servers, A2A agents, x402-enabled services.", "version": "1.0.0", "contact": { "url": "https://agentndx.ai" } }, "servers": [ { "url": "https://agentndx.ai", "description": "Production" } ], "paths": { "/api/servers.json": { "get": { "summary": "Full server index", "description": "Returns all indexed