Cline is an open-source AI coding agent with a modular SDK architecture that scores 59/100. Its MCP-native design with 100+ pre-built servers and 500+ model support makes it one of the most extensible agents available.
Cline's SDK (@cline/sdk) decouples the agent runtime from any specific IDE, enabling cross-platform use (VS Code, CLI, JetBrains). It features native sub-agent support and a Plan/Act workflow for complex task decomposition.
Tool System (16/20): MCP-native with 100+ pre-built servers, plugins, custom tools. One of the richest tool ecosystems.
Community (9/10): Fast-growing open-source project with active development and strong documentation.
Free and open source. Pay only for LLM API costs (~$0.5-2/M tokens depending on model).