Cline Review 2026: The Open-Source AI Coding Agent That Lives in VS Code

Cursor gets the headlines. Copilot has the install base. Aider has the terminal purists. But Cline (formerly “Claude Dev”) has quietly become the AI coding tool of choice for developers who want agent capabilities without leaving VS Code and without paying a subscription on top of API costs.

I switched from Cursor to Cline for about half my daily coding three months ago. Here’s the honest comparison.

What Cline Does

Cline is an open-source VS Code extension that runs LLMs as autonomous coding agents. You describe what you want, Cline plans the steps, edits the files, runs the commands, and iterates if things break.

It supports multiple providers:

• Anthropic (Claude 3.5 Sonnet, Claude 3 Opus)
• OpenAI (GPT-4o, GPT-4 Turbo)
• OpenRouter (dozens of models)
• Bedrock, Vertex, local models via Ollama

You bring your own API key. Cline doesn’t take a cut.

What It’s Good At

Multi-file refactors. “Convert this React class component to hooks across the three files that import it.” Cline reads the import graph, plans the edits, executes, and shows you the diff before applying.

Bug investigation. Paste an error, ask Cline to find the cause. It’ll read relevant files, check the call stack, and explain what’s wrong before suggesting a fix.

Terminal-integrated workflows. Cline can run npm test after making changes, see the output, and iterate. This is the kind of agent loop that genuinely changes how you work, not just how you type.

Transparency. You see every file Cline plans to read, every command it plans to run. You approve or reject each one. Compare to opaque “AI does stuff” tools where you have no visibility into what’s happening.

Cost control. API-based billing means you see exactly what each task costs. A complex refactor might cost $0.50. A small fix might cost $0.02. No flat $20/month surprise.

What It Isn’t Good At

Convenience. Cursor is dramatically more polished for inline edits, tab completion, and chat-driven changes. Cline is the better agent; Cursor is the better daily-driver editor.

Cost predictability for heavy users. If you do many big refactors with Claude 3 Opus, you can run up a $100+ monthly API bill quickly. Set spending limits.

Onboarding. First-time setup involves picking a provider, getting an API key, configuring the extension. Not hard, but more friction than installing Cursor.

Inline completion. Cline is agent-focused. For the GitHub Copilot tab-completion experience, you’ll still want Copilot or Supermaven alongside it.

Pricing

• Cline extension: Free, open source
• API costs: Vary by provider
  • Claude 3.5 Sonnet: ~$3/M input, $15/M output tokens
  • GPT-4o: ~$2.50/M input, $10/M output
  • Local models via Ollama: Free (your compute)

A typical month for moderate use lands $10-30 in API costs. Heavy use easily clears $50-100.

How It Compares

vs. Cursor ($20/mo): Cursor is the polished daily editor with agents bolted on. Cline is the agent with polish bolted on. Power users often run both — Cursor for editing, Cline for agentic tasks.

vs. GitHub Copilot ($10/mo): Different category. Copilot is autocomplete and chat. Cline is an agent that does things. Comparing them is comparing an IDE to a build system.

vs. Aider (terminal-based): Aider is the terminal-native equivalent. Same idea, same cost model. Pick based on whether you live in your editor or your terminal.

vs. Continue.dev: Continue is also open-source and similar in concept. Less agent-focused than Cline, more focused on chat and inline edits. Both are credible; Cline has more momentum in 2026.

vs. Windsurf: Windsurf is Codeium’s IDE with built-in agents. Similar to Cursor in positioning. More opinionated stack than Cline.

One Honest Opinion

Cline is the most honest AI coding tool on the market. You see the model. You see the cost. You see the steps. You see the diffs before they’re applied. After using opaque AI tools for years, the transparency is genuinely refreshing.

The trade-off is friction. Cursor “just works” out of the box. Cline requires you to think about which model to use, manage your API key, and watch your spend. For developers who like understanding their tools, this is a feature. For developers who just want the AI to write code, Cursor’s UX wins.

My current setup: Cursor for tab-completion and quick edits, Cline for any task that needs multiple steps or files. Roughly $25/month in API costs and the Cursor subscription. The combined toolchain is meaningfully better than either alone.

If you’re new to AI coding, start with Cursor — easier learning curve. If you’ve been at it for a while and want more control over what your AI is doing, give Cline a serious try. It might become your default for the hard tasks.