MCP Server Tester is an open-source, browser-based tool for inspecting remote MCP servers before you wire them into an agent. Paste a URL to list tools, resources, and prompts, plus: - LLM Readiness Score (A–F) for tool-schema quality - Tool-poisoning & rug-pull detection (heuristic) - Per-request token cost estimates - OAuth / auth inspector - Compare mode for two servers - Exportable Markdown / JSON reports with secret redaction Runs locally or as a hosted demo. MIT-licensed, no signup.