Cline is an open source AI coding assistant that runs as a VS Code extension and in the terminal. The core proposition is transparency: you pick your own LLM, you pay only for API calls at the provider rate, and every token of cost is visible. There is no subscription fee, no credit system, and no opaque pricing tier.
Cline was one of the first tools to implement the Model Context Protocol (MCP) as a first class feature, which means it can connect to external services, databases, and APIs through a standardized interface. This makes Cline significantly more extensible than closed platform alternatives.
The tool supports any LLM provider that exposes an API: OpenAI, Anthropic, Google, local models via Ollama, or any OpenAI compatible endpoint. Running a local model means your code never leaves your machine, meeting the strictest data sovereignty requirements.
The trade off is setup complexity. You need API keys, you need to understand token pricing, and you need to manage your own cost controls. For developers comfortable with this, the cost advantage is significant. A typical month of heavy Cline usage costs $15 to $40 in API calls, compared to $20 to $60 for equivalent subscription tools.