Claude Code
Anthropic's agentic coding tool that runs in terminal, IDE, and web; reads code, edits, runs commands.
- Loop: Read → Plan → Edit → Verify, with permission gates.
- Supports MCP servers, hooks, slash commands, subagents.
- CLAUDE.md provides project-level persistent rules.
When to use: For agentic multi-file work, large codebases, and CI/headless automation.
Example: "Read auth flow, find why session refresh fails on Safari, write fix + test." Claude reads, edits, tests, asks before push.