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CLITerminal & CLI harnesses

Claude Code

by Anthropic
Supports 4 models · CLI · Included with Claude Pro/Max subscription (~$20-100/mo); API usage billed separately · Defaults: Claude Sonnet 4.6

Claude Code is a proprietary command-line tool for AI-assisted coding, built by Anthropic (released 2025-02). Claude Code integrates with 4 verified models, including Claude Sonnet 4.6, Claude Opus 4.6, and Claude Haiku 4.5. Pricing starts at Included with Claude Pro/Max subscription (~$20-100/mo); API usage billed separately. Engineers run it from a terminal, where it can inspect repositories, edit files, call tools, and drive repeatable agentic coding workflows across local projects.

Overview

Autonomous coding agent that runs in the terminal, capable of editing files, running commands, and managing the entire development workflow with minimal human intervention.

Featured Model Specs

ModelLabReleasedContextReasoningOpen source
Claude Sonnet 4.6Anthropic2026-02-171MYesNo
Claude Opus 4.6Anthropic2026-02-051MYesNo
Claude Haiku 4.5Anthropic2025-10-01200KNoNo
Claude Sonnet 4.5Anthropic2025-09-29200KYesNo

Model Compatibility Matrix

ModelLabDefaultAccess tierNotes
Claude Sonnet 4.6AnthropicYesProDefault model
Claude Opus 4.6AnthropicNoProMost capable model
Claude Haiku 4.5AnthropicNoProFast, lightweight model
Claude Sonnet 4.5AnthropicNoPro

Underlying Models

Compare to Similar Harnesses

FAQ

What is Claude Code?

Claude Code is a proprietary command-line tool for AI-assisted coding, built by Anthropic (released 2025-02). Engineers run it from a terminal, where it can inspect repositories, edit files, call tools, and drive repeatable agentic coding workflows across local projects. It is primarily used for agentic coding from a local shell.

What models does Claude Code support?

Claude Code runs Claude Sonnet 4.6, Claude Opus 4.6, Claude Haiku 4.5, Claude Sonnet 4.5.

How much does Claude Code cost?

Claude Code costs Included with Claude Pro/Max subscription (~$20-100/mo); API usage billed separately.

Is Claude Code open source?

No, Claude Code is a proprietary command-line tool.

What are alternatives to Claude Code?

Alternatives include Pi, Aider, and Warp.

When was Claude Code released?

Claude Code was released in 2025-02.

Explore Related Pages

Last reviewed: 2026-05-15. Data sourced from harness documentation and provider pages.