Cline

Open-source AI coding agent that runs as a VS Code extension with full tool use

0Code & DevelopmentOpen Source

Editorial Review

Cline has emerged as the best free AI coding agent that lives inside VS Code. Where Cursor is its own paid editor and Copilot is a paid GitHub extension, Cline is an open-source extension that turns vanilla VS Code into a fully agentic IDE — file edits, terminal commands, web browsing, multi-step planning — without you switching editors or paying a subscription. The cost model is BYO API key, identical to Aider. Combined with DeepSeek or Anthropic prompt caching, it's possible to run heavy daily Cline use for $5-30/mo in API spend instead of $20-200/mo subscriptions. The trade-off versus Cursor or Claude Code is polish: a few rough edges in the UI, occasional tool-use loops, and the multi-mode (Plan/Act) split takes some getting used to. For VS Code loyalists who want a serious coding agent without changing editors or vendor-locking, it's the strongest choice.

Key Features

Open-source extension for VS Code, JetBrains, Cursor, Windsurf, Zed, Neovim — plus a preview CLIRead/edit files with diff previewRun terminal commands with approval

About Cline

Cline (formerly Claude Dev) is an open-source AI coding agent that runs as an extension for VS Code, JetBrains, Cursor, Windsurf, Zed, Neovim, and increasingly as a standalone CLI. It can read and edit files, execute terminal commands, browse the web, and chain multi-step tasks — all from within your editor. Bring-your-own LLM via Anthropic, OpenAI, OpenRouter, or local models.