Cline Review 2026: The Open-Source Agent That Lets You Bring Your Own Model

TL;DR

Cline (formerly Claude Dev) is an open-source AI coding agent extension for VS Code. Bring your own API key (Anthropic, OpenAI, OpenRouter, local Ollama), watch the agent plan and execute step-by-step, pay only for actual tokens used. For developers comfortable with API billing it is the most flexible agent on the market.

What it does

Cline installs as a VS Code extension and acts as an autonomous coding agent. You give it a task, it plans, reads files, edits code, runs terminal commands, and asks for approval at each step. The differentiators:

• BYO model — Anthropic, OpenAI, OpenRouter, Bedrock, Azure, local Ollama, LM Studio
• Step-by-step approval — see every read, edit, and command before it runs
• Cost-transparent — running token cost shown live in the panel
• MCP support — extend it with any Model Context Protocol server
• Plan/Act mode — separate phases for safer execution
• Open source under Apache 2.0

What is great

Total transparency. You see every file Cline reads, every diff before it applies, every command before it runs. After Cursor's sometimes-opaque agent, this is refreshing.

No subscription tax. Pay your model provider directly. Heavy users with API rate-limit deals or volume discounts can come out far cheaper than $20+/month subscriptions.

Local model support is real. Run Cline against Ollama with Qwen 3 Coder or DeepSeek V3 locally — slower than Claude Sonnet but completely offline and free.

MCP ecosystem. Cline is one of the easiest places to plug in MCP servers — file system tools, browser automation, custom tooling all extend the agent naturally.

What is not

You manage your own bill. Without a subscription cap, an agentic loop on Claude Opus can rack up real dollars fast. Set provider-side spending limits before you start.

Less polished than Cursor. UI is functional rather than beautiful. Some workflows that feel natural in Cursor require manual config in Cline.

No proprietary Tab model. Cline is agent-only — for tab-style autocomplete you still want Copilot, Cursor, or Supermaven alongside it.

Setup friction. Pasting API keys, picking providers, configuring MCP servers — it is more upfront work than Cursor's one-click sign-in.

Pricing

Cline itself is free and open source. Costs are 100% pass-through to your chosen model provider:

Provider	Typical cost for an active dev day
Anthropic Claude Sonnet 4.5	$3–10
Anthropic Claude Opus	$15–50
OpenAI GPT-5	$5–15
DeepSeek V3 (via API)	$0.20–1
Local Ollama / LM Studio	$0

Cline also offers a managed billing layer for teams that want a single invoice without managing provider keys.

Verdict

Cline is the right answer for developers who want maximum control, transparency, and flexibility. It is not as polished as Cursor or Windsurf, but it does not need to be — its core promise is "you see and pay for exactly what happens" and it delivers. The open-source roots mean it will be around regardless of which AI lab is currently winning.

Who it is for

Best for: Developers comfortable with API billing, regulated teams needing local-model fallback, MCP power users, and anyone allergic to opaque agent behavior.

Not for: Beginners who want subscription simplicity, or developers who need first-class Tab completion in addition to agent mode.