Cline CLI 2.0: The Coding Agent Built for the Terminal

TL;DR

• Cline CLI 2.0 brings the full VS Code agent experience to the terminal with a redesigned TUI
• Run multiple isolated agents in parallel using tmux or terminal splits — each with independent state and models
• Headless mode with stdin/stdout support makes Cline scriptable in CI/CD pipelines and shell workflows
• ACP protocol support means the same agent works in JetBrains, Zed, Neovim, and Emacs

The Big Picture

The IDE sidebar made sense when AI coding assistants were glorified autocomplete. You'd write a function, the assistant would suggest the next line, you'd accept or reject. The human was still writing code one cursor at a time.

That model broke the moment agents got good enough to refactor entire modules, update test suites, and generate migration scripts without hand-holding. When your workflow shifts from "write this function" to "refactor this database layer on a feature branch while updating the API docs," the sidebar becomes a bottleneck. You're not editing files anymore. You're orchestrating systems.

Cline CLI 2.0 recognizes this shift. It takes the full agent experience from the VS Code extension and rebuilds it for the terminal, where parallel sessions, piped I/O, and composable workflows have been native for decades. The result is a coding agent that works like infrastructure: scriptable, automatable, and designed to run in parallel without stepping on itself.

This isn't about replacing the IDE. It's about meeting developers where different kinds of work actually happen. Visual debugging in an unfamiliar codebase? IDE wins. Orchestrating three agents across three branches while piping schema diffs through stdin? Terminal wins. Cline now works natively in both.

How It Works

Launch cline and you're dropped into a terminal UI that mirrors the interaction patterns from the VS Code extension. Settings panel navigated with keystrokes. Mode toggle with Tab. Streaming responses with inline markdown rendering. The agentic loop is identical: same tools, same model support, same reasoning process. The difference is the surface.

Press Tab to switch between Plan and Act modes. In Plan mode, Cline reasons through your codebase before touching anything. You see the strategy unfold, approve each step, or hit shift+tab to enable auto-approve and let it run. Change models mid-session based on task complexity. The TUI makes the agent's decision-making visible without forcing you out of the terminal.

Slash commands handle common workflows. Type /history to resume a previous task. /settings to change configuration without restarting. Drop a markdown file like pr-review.md into your custom workflows directory and it becomes /pr-review automatically. The command surface is designed for speed, not discovery.

The real unlock is parallel agents. In an IDE, running multiple agent instances means multiple windows, careful state isolation, and manual window management. Nobody does it because it's painful. In a terminal, you already know how to do this: open tmux, split into panes, run a process in each one. Cline CLI instances are fully isolated. Each maintains its own state, conversation history, and model configuration. One agent refactors your database layer while another updates API docs on a different branch. No shared state. No conflicts.

This workflow pattern only becomes natural when your interface supports parallel views. The TUI makes each instance's progress visible and interactive independently. You're not managing windows. You're managing work.

Headless mode strips away the TUI entirely. The -y flag gives Cline full autonomy. Everything streams to stdout. Full stdin/stdout support means you can pipe content in, chain commands, and treat Cline as another building block in your shell workflow. This makes the agent usable in GitHub Actions, GitLab CI, Jenkins, shell scripts, cron jobs — anywhere you can run a command.

JSON mode (--json) streams structured output for programmatic use cases. You can build tools on top of Cline or integrate it into existing automation. The agent becomes part of your pipeline, not a separate tool you context-switch to.

The --acp flag turns Cline into an ACP-compliant agent. ACP (Agent Client Protocol) standardizes how coding agents and editors communicate, similar to what LSP did for language servers. That means Cline works in JetBrains, Zed, Neovim (via CodeCompanion or avante.nvim), Emacs, and any other editor that speaks the protocol. Your coding agent shouldn't lock you into a specific tool. The same agent, the same configuration, the same design attention carries into whatever editor you already use.

Configuration stays out of your way. Run cline auth to set up your provider: Cline's native provider, OpenAI, Anthropic, Bedrock, Vertex, and more. Use cline config to toggle YOLO mode, change your default model, or configure Plan mode to use a different model than Act mode. Need multiple configurations? Pass the --config flag to point to a different settings directory. Run one terminal with Claude for planning, another with a fast model for implementation. Each instance maintains its own state.

What This Changes For Developers

The workflow shift is immediate. Instead of opening VS Code, navigating to the Cline sidebar, and typing a prompt, you stay in your terminal and type cline "refactor the auth module". The agent runs in the same environment where you're already running tests, managing git branches, and tailing logs. Context switching drops to zero.

Parallel agents change how you think about task decomposition. Before, you'd give an agent a complex task and hope it could handle all the pieces. Now you split the work: one agent handles the refactor, another updates the tests, a third generates the migration. Each runs in its own pane. You monitor progress across all three with a glance. If one gets stuck, you intervene without stopping the others.

This mirrors how senior developers already work. You don't do everything sequentially. You start a build, switch to another branch to review a PR, come back to check the build output, start another task while the first one's still running. The terminal has always supported this workflow. Cline CLI makes the agent fit into it.

Headless mode unlocks automation patterns that weren't possible before. Automated code review in CI: git diff origin/main | cline -y "Review these changes for issues". Generate release notes from commit history: git log --oneline v1.0..v1.1 | cline -y "Write release notes". Run tests and fix failures with a timeout: cline -y "Run tests and fix failures" --timeout 600. The agent becomes a pipeline stage, not a separate tool.

ACP support means you're not locked into a single editor. If you've built your workflow around Neovim or you're trying out Zed, you don't have to give that up to use Cline. The same agent, the same configuration, the same capabilities work everywhere. This matters more as agents become infrastructure. You don't want your coding agent to be the thing that forces you into a specific editor.

The Cline API integration means you can use one key across Claude, Gemini, GPT, and more. For a limited time, Minimax M2.5 and Kimi K2.5 are free to use with no API key required. The barrier to entry is zero. You can start using Cline CLI without signing up for anything or entering payment information.

Try It Yourself

# Install globally
npm install -g cline

# Set up authentication
cline auth

# Run interactively
cline "refactor the database layer"

# Headless mode for automation
git diff origin/main | cline -y "Review these changes for issues"

# Generate release notes from commits
git log --oneline v1.0..v1.1 | cline -y "Write release notes"

# Run with a timeout
cline -y "Run tests and fix failures" --timeout 600

# Use ACP mode for editor integration
cline --acp

# Custom config directory
cline --config ~/.cline-work "update API docs"

For parallel agents, open tmux and split into panes:

# Start tmux session
tmux new -s cline-work

# Split into three panes (Ctrl+b then ")
# In pane 1:
cline "refactor database layer on feature/db-refactor"

# In pane 2:
cline "update API documentation"

# In pane 3:
git diff schema.sql | cline "generate migration scripts from this schema diff"

Full docs at docs.cline.bot/cline-cli. Source code at github.com/cline/cline.

The Bottom Line

Use Cline CLI if you're already living in the terminal and want your coding agent to fit into that workflow. Use it if you need to run multiple agents in parallel without fighting your IDE. Use it if you want to automate agent tasks in CI/CD pipelines or shell scripts. Use it if you're in Neovim, Zed, or JetBrains and don't want to switch editors just to use a better agent.

Skip it if you rarely leave your IDE and the sidebar workflow is working fine. The VS Code extension isn't going anywhere. Skip it if you're not comfortable in the terminal or don't have workflows that benefit from parallel sessions or automation.

The real shift here isn't technical. It's conceptual. Cline CLI treats the coding agent as infrastructure, not as a sidebar feature. That means it needs to work everywhere: in your editor, in your terminal, in your CI pipeline, in your shell scripts. The terminal was always built for orchestration. Cline CLI is the first coding agent designed to take full advantage of that. If your work has shifted from writing individual lines to orchestrating systems, this is the interface that finally fits.

Source: Cline