Cline

Cline is an open-source coding agent that runs in your IDE and terminal. It reads and writes files, runs terminal commands, uses a browser, and builds features through conversation, but it does none of that silently. Every file edit and every terminal command surfaces for your approval first, so you always see and confirm what changes. It is released under the Apache-2.0 license by Cline Bot Inc. and is written in TypeScript.

Its most-used surface is the Visual Studio Code extension, where edits appear in a diff view you approve or reject. Cline has since grown a command-line interface, a JetBrains plugin, and a Kanban board, all built on the same agent core. Cline is model-agnostic: you bring your own API key for a cloud or local model, and it also offers hosted billing options if you prefer not to manage keys.

Where Cline sits in the stack

Installation

Cline installs from the Visual Studio Marketplace as a VS Code extension. There is also an official command-line interface.

# Command-line interface
npm i -g cline

For the editor extension, search for “Cline” in the VS Code Extensions view, or install the extension id saoudrizwan.claude-dev. A JetBrains plugin and a Kanban web board (npx kanban) are also available.

Two ways to use it

The first pattern is plan then act. You start a task in Plan mode, where Cline explores the codebase, asks clarifying questions, and lays out a strategy without changing anything. Once you agree, you switch to Act mode and Cline executes the plan, surfacing each edit for approval.

# In Plan mode
"Explore how auth is handled and propose where to add refresh tokens."
# Cline reads files, asks questions, and writes a plan.

# Switch to Act mode
"Looks good, implement it."
# Cline edits files and runs commands, one approval at a time.

The second pattern is connecting an MCP server so Cline can reach systems beyond your files, such as a database or a cloud API. Once attached, the agent can query those systems as part of a task, still gated by your approvals.

{
  "mcpServers": {
    "postgres": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-postgres", "postgresql://localhost/mydb"]
    }
  }
}

Typical workflow

How it compares

When not to use it

• You want fully unattended automation. Cline is built around per-action approval. For hands-off, long-running jobs where you cannot review each step, an autonomous agent such as OpenHands fits better.
• You cannot grant local file and shell access. Cline runs inside your IDE and terminal with real access to your machine. In locked-down environments that is not allowed.
• You want a pure terminal tool. If you live in the command line and do not want an editor extension, Aider or OpenCode is a closer fit.
• You want one vendor’s managed stack. If you only use Anthropic models and want native subagents and hooks, Claude Code is purpose-built for that.

Further reading

• Cline documentation : official setup, plan and act modes, MCP, and provider configuration.
• Cline on GitHub : source and issues under the Apache-2.0 license.
• Open-source coding agents compared : where Cline sits among the alternatives.
• Cursor : the AI-native editor Cline is often compared against.
• What is the Model Context Protocol? : the standard Cline uses to reach external systems.
• Agentic loops : the read-plan-edit-run cycle behind every coding agent.

Sources

• Cline documentation : definition, plan and act modes, approvals, checkpoints, MCP, and supported providers.
• Cline on GitHub : Apache-2.0 license, TypeScript, VS Code and CLI surfaces, and provider list.