Cline: the autonomous coding agent for your editor

Cline is the coding agent that runs *inside your editor* — the open-source answer to 'I want Claude Code, but in VS Code, with the model I choose'. It plans, edits across files, runs commands, and shows you every diff before it touches your tree. Approval gates are the product: full agent autonomy, with explicit consent at every step.

What it actually does

• Plan → Act loop — the agent drafts a plan first (read code, propose changes), you approve, then it executes with step-by-step diffs and command approvals.
• Bring your own key — Anthropic, OpenAI, Google, OpenRouter, local Ollama/vLLM — one extension, every provider.
• MCP support — Cline speaks the Model Context Protocol; wire it to databases, Figma, browsers, your own tools.
• Autonomous but gated — browser use, file edits, terminal commands, all permissioned; trust grows, keys stay yours.

Why it's everywhere

VS Code is home for a huge share of developers, and Cline made agent-loop editing feel native there — approval UX that isn't annoying, cost transparency per task, massive model choice. When you want the agent to do real work instead of suggesting snippets, this is the reference extension.

Who it's for

• VS Code users who want an agent, not autocomplete.
• Teams standardizing on bring-your-own-key model budgets.
• Anyone mixing local models with frontier providers in one harness.

What to check

• Open source — audit the extension before installing; it executes filesystem and shell actions by design.
• Token cost is metered per session — local models make it free, frontier models make it finite. Know which mode you're in.
• Context window discipline matters as much as model choice — long tasks drift; checkpoint often.

Cline is the proof you don't need a new IDE to get agent-class assistance — the tool layer got there first. Repository: github.com/cline/cline.