Cline

Cline is an open-source AI coding agent designed to integrate seamlessly into development environments, providing developers with a conversational interface to read and write code, run commands, and build features through natural language. It operates within editors like Visual Studio Code, JetBrains, and the terminal, offering a transparent and controllable AI experience. Unlike traditional code completion tools, Cline executes complete development workflows from a single prompt, including analyzing codebases, creating and editing files, running terminal commands, and interacting with browsers for frontend testing. Every action requires explicit approval from the developer, ensuring full control over the codebase.

Founded in 2024 by Saoud Rizwan, Cline has rapidly gained traction in the developer community. By April 2026, the Cline VS Code extension had surpassed 1.5 million installs, making it one of the most popular open-source AI coding agents. The project is MIT-licensed and has attracted significant investment, securing $32 million in combined seed and Series A funding in July 2025, led by Emergence Capital and Pace Capital. This funding has facilitated the expansion of Cline's capabilities and integrations.

Cline's flagship product is its AI coding agent, which supports various development environments, including VS Code, JetBrains, and the terminal. The agent can read and write files, run terminal commands, and use a browser to assist in building features through natural language. It is model-agnostic, allowing developers to connect their own API keys from providers like Anthropic, OpenAI, Google Gemini, AWS Bedrock, and Azure, or to use local models via platforms like Ollama. This flexibility enables developers to choose the most suitable model for their needs.

Cline's customer base includes individual developers and large engineering organizations that value transparency and control in their development processes. The company's open-source nature and model-agnostic approach have positioned it as a leading choice for developers seeking autonomy in their coding workflows. Cline's main competitors include other AI coding agents like GitHub Copilot and Tabnine, but its emphasis on human-in-the-loop approval and flexibility in model selection distinguish it in the market.