Cline

VS Code extension agent — ~4M installs in 2026. Plan/Act mode, autonomous file edits with diff approval, terminal access. The leading open-source IDE agent.

Install as a VS Code extension: open VS Code, go to Extensions (Ctrl+Shift+X), search "Cline", install. Or install via CLI: code --install-extension saoudrizwan.claude-dev. Cline is a VS Code and Cursor extension that provides an AI coding agent with file editing, terminal execution, and browser automation capabilities. After install, configure an API provider in Cline's settings (gear icon in the Cline sidebar). Supported: Anthropic, OpenAI, Google Gemini, OpenRouter, and local models via Ollama or OpenAI-compatible endpoints. For Anthropic: enter your API key and select Claude Sonnet or Opus. For local models via Ollama: set API provider to "Ollama" (no API key needed) and select a model. Open the Cline sidebar (Ctrl+Shift+P → "Cline: Focus on Cline View"), type a task like "Create a React login form with validation", and Cline autonomously creates files, runs commands, and iterates. Verify it works by asking "What files are in this project?" — Cline runs ls in the integrated terminal and reports results. Time-to-first-action: ~15 seconds per request including model latency.

Best for: VS Code/Cursor users who want autonomous multi-step AI coding (create project, implement feature, run tests, debug, iterate), developers who prefer an IDE-integrated agent over a separate terminal tool, tasks requiring terminal command execution as part of the development workflow, browser-based debugging and inspection (Cline can navigate and interact with web pages), workflows where the AI needs to observe command output and course-correct. Not suited for: developers who prefer terminal-native tools (use Claude Code or Aider), JetBrains IDE users (Cline is VS Code-only), lightweight inline completions without agent overhead (use GitHub Copilot or Continue), projects requiring WSL2 or remote SSH without the VS Code Remote extension setup.

Use Cline when you want an autonomous AI coding agent inside VS Code with full terminal access, file editing, and browser automation — it can spin up dev servers, run tests, and debug iteratively without constant manual prompts. Switch to Claude Code when you prefer terminal-native agentic coding outside an IDE. Use Aider for git-native pair programming with explicit diffs — Cline is more autonomous, Aider is more collaborative. Use Continue for inline completions and IDE-integrated chat that stays closer to the cursor — Cline is agentic, Continue is assistive. Use Cursor for an AI-native IDE experience where everything is built-in rather than an extension. Cline's strength: agentic autonomy with permission gates — it asks before terminal commands, file operations, or API calls, giving you control over its agency. Best for developers who want AI to execute multi-step tasks unsupervised.

Problem: "Cline is waiting for you to approve this action" on every single file edit. Fix: In Cline settings, toggle "Auto-approve read-only operations" and "Auto-approve file changes." By default, Cline gate-checks every operation — useful for safety, tedious for fast iteration. The permission model is configurable per operation type (read, write, terminal, browser). Problem: Terminal commands fail with "command not found" or wrong toolchain. Fix: Cline inherits the VS Code integrated terminal environment, which may differ from your system shell. Ensure your shell config (.zshrc, .bashrc) is sourced by VS Code's terminal. Use Cline's "Terminal Settings" to explicitly set the shell path. Problem: Context window fills up, Cline loses track of earlier edits. Fix: Cline maintains conversation context in the VS Code workspace state. On long sessions, use "Start New Task" (or Cmd+Shift+P → "Cline: New Task") to reset context. Long-running autonomous tasks sometimes benefit from checkpoint restarts.