Claude Code is Anthropic's coding agent for repository-scale engineering work. It reads files, edits code, runs commands, and coordinates subagents from the terminal, supported IDEs, the Claude desktop app, or a browser. Its strongest fit is a Claude-centered workflow that needs configurable permissions, persistent project instructions, and integrations with development infrastructure.
Codex is OpenAI's coding agent across the CLI, IDE extension, desktop app, web, SDK, and cloud. Local sessions work directly in your repository with configurable sandbox and approval policies. Cloud tasks clone the repository into isolated OpenAI-managed environments, making Codex useful for parallel jobs that can run while you work elsewhere.