--- title: MCP server scanner — grade a live MCP server description: Connect to a live MCP server and grade its tools, resources, and prompts against MCP best practices. MCP quality score with a fix for every issue. last_updated: 2026-06-15 canonical_url: https://agent-ready.dev/mcp-server-scanner --- # MCP server scanner — grade a live MCP server > Connect to a live, remotely-hosted MCP server and grade its tools, resources, and prompts against MCP best practices. Get an MCP quality score (0–100) with a plain-English fix for every issue. ## How it differs from the MCP card validator The [MCP card validator](https://agent-ready.dev/mcp-card-validator) is **static** — it fetches and checks your `/.well-known/mcp.json` card. The MCP server scanner is **live** — it speaks the protocol (`initialize` → `tools/list` / `resources/list` / `prompts/list`) to the running server and grades the real definitions it returns. It's read-only: it enumerates tool definitions, it never calls your tools. ## What it checks (the MCP score) Tool quality is weighted most heavily, because tool definitions are what an agent reasons over. - **Tool descriptions** — every tool has a non-empty description - **Parameter descriptions** — every input field is documented - **Output schemas** — every tool declares an `outputSchema` - **Annotations** — `readOnlyHint` / `destructiveHint` / `idempotentHint` / `openWorldHint` / `title` - **Naming** — unique, agent-safe tool names (snake_case recommended) - **Server metadata** — name, version, title, description, website, icon in `serverInfo` - **Resources & prompts** — URIs, MIME types, and descriptions where offered - **Capability honesty** — declared capabilities are actually populated (no drift) - **MCP Apps (UI)** — interactive `ui://` resources carry a `text/html` MIME type ## Scope Remote **http(s)** MCP endpoints only (Streamable HTTP). stdio servers — the npm packages that run locally — aren't reachable from a hosted scanner. Discovery is unauthenticated; if a server requires auth even for discovery, the scanner reports that and grades the reachable surface. ## Frequently asked questions ### What is the MCP server scanner? It connects to a live, remotely-hosted MCP server over Streamable HTTP, runs the protocol handshake, and grades the advertised surface — tools, resources, and prompts — against MCP best practices. It returns an MCP score (0–100) with a plain-English fix for each issue. It's read-only: it never calls your tools, only enumerates their definitions. ### How is this different from the MCP card validator? The MCP card validator is static: it fetches and checks your /.well-known/mcp.json card. The MCP server scanner is live: it actually speaks the protocol to the running server and grades the real tool/resource/prompt definitions it returns. Card validator = 'is my card discoverable and well-formed?'; server scanner = 'is the running server actually high quality?'. ### What does the MCP score measure? Tool quality (descriptions on every tool, descriptions on every parameter, output schemas, annotations, naming), server metadata richness (name, version, title, description, website, icon), resource and prompt quality, capability honesty (declared capabilities that the server actually serves), and whether interactive MCP-Apps (ui://) resources carry the right MIME type. Tool quality is weighted most heavily. ### Can you scan a local (stdio) MCP server? No. A hosted scanner can only reach remotely-hosted MCP servers over http(s) (Streamable HTTP). stdio servers — the npm packages that run on your own machine — aren't reachable over the network, so paste a remote endpoint URL instead. ### Does the scanner need authentication? No. It performs an unauthenticated handshake and discovery (initialize, tools/list, resources/list, prompts/list), which most servers allow before auth. If a server requires authentication even for discovery, the scanner reports that and grades whatever surface it can reach. --- Scan an MCP server on the web: Related: [MCP card validator](https://agent-ready.dev/mcp-card-validator) · [How to publish an MCP server card](https://agent-ready.dev/how-to-publish-an-mcp-server-card) ## Sitemap See the full [sitemap](https://agent-ready.dev/sitemap.md) for all pages on agent-ready.dev.