Claude Code

Claude Code is an agentic coding tool created by Anthropic. It reads your entire codebase, edits files, runs commands, and integrates with your development tools. It works in the terminal, IDEs (VS Code, Cursor, JetBrains), a desktop app, the browser, and Slack — all surfaces use the same underlying engine, so CLAUDE.md files, settings, and MCP servers work consistently everywhere.

History

Claude Code was announced on February 24, 2025 as a limited research preview, alongside the Claude 3.7 Sonnet model. It reached general availability in May 2025 with Claude 4. On October 20, 2025, Anthropic launched a web version of Claude Code and a sandboxing feature. The tool gained significant popularity during the 2025-2026 winter holidays.

Capabilities

• Agentic search — understands project structure and dependencies without manual context-file selection.
• Coordinated multi-file edits, bug fixing, writing and running tests, refactoring.
• Git workflow — stages changes, writes commit messages, creates branches and pull requests. In CI: GitHub Actions, GitLab CI/CD.
• Computer use (since March 2026) — opens apps, navigates the browser, runs dev tools.
• Agent teams and dynamic workflows — execution across tens to hundreds of parallel sub-agents with result verification. Agent SDK for building custom agents.
• Customization via CLAUDE.md, skills, hooks, and integration with external data sources through MCP (Model Context Protocol).

Security and control

Claude Code runs locally in your terminal and talks directly to the model APIs, with no backend server or remote code index. It asks for permission before making changes to files or running commands. It works on macOS, Linux, and Windows.