Cline is an open-source coding agent that lives inside VS Code as an extension: it reads your project, plans changes, edits multiple files, runs terminal commands and asks for approval at every step. It sits at roughly 70,000 stars on GitHub, and its selling point is not price (the software is free) but model freedom: you bring your own API key, from Anthropic and OpenAI to local models served through Ollama.
Official repository information
Platform: GitHub. Organisation: cline. Project name: cline. Licence: Apache-2.0. It started out as Claude Dev, and today there is also a JetBrains plugin and a command-line version alongside the VS Code extension.
Why so many developers use it
First, no subscription lock-in: if you already have API access, you pay only for actual usage. Second, the Plan and Act modes: discuss the work plan first, then let it execute, with checkpoints that can roll changes back. Third, extensibility through MCP, which connects databases and outside services. For developers who dislike handing their whole environment to a closed editor, this is a coherent package.
The cost hides in token consumption
Cline itself charges nothing, but every step ships context to the model: file trees, file contents, command output, error logs. On longer tasks a single session can quietly eat a budget that a subscription user would not notice for half a month. Connect a flagship model and let the agent rework a large repository, and you should look at the API bill before, not after. Cheaper or local models cut the bill, but their planning and self-correction are visibly weaker.
Who it fits, who it does not
It fits developers who want to stay in VS Code, choose their own model and approve each step. It fits beginners who expect a turnkey experience far less: key management, model choice and cost control are all on you. Teams under strict compliance also need to check where code flows with the chosen API; open source alone does not answer that.
My verdict: if you already live on API accounts and like control, Cline is one of the strongest open agent frameworks around. If you only complete a few lines now and then, a subscription editor is the more honest deal.
