Bash Tool - Claude Code
Execute shell commands with persistent working directory in project bounds.
The Bash tool runs shell commands. It's the most capable and most-permissioned tool in Claude Code, which is why every session has at least one rule about it.
What it does
Bash runs a command in a persistent shell whose working directory sticks within the project. Output comes back as combined stdout+stderr, truncated if huge. You can run it in the background for long processes, pipe, use heredocs, and chain commands. Permission rules gate which commands are allowed.
When to use it
- Running tests, builds, linters, and formatters.
- Git operations, file system changes, and installs.
- Anything that's faster as a one-liner than a tool sequence.
- Invoking project-specific CLIs.
Gotchas
- Interactive prompts hang the tool. Pass flags or pipe input instead of waiting for TTY.
- Shell state (exported vars,
cdin subshells) doesn't persist beyond a single call unless you chain with&&. - Newlines are blocked in command strings on some setups. Use quoted strings or here-docs for multi-line payloads.
Official docs: https://code.claude.com/docs/en/tools-reference.md#bash-tool-behavior
Technical content at the intersection of AI and development. Building with AI agents, Claude Code, and modern dev tools - then showing you exactly how it works.
Newsletter
Get the weekly deep dive
Tutorials on Claude Code, AI agents, and dev tools, delivered free every week.
Was this helpful?
Related Guides
Related Tools
AgentCanvas
A hosted infinite canvas your headless AI agents drive over MCP. Any MCP-speaking agent - Claude Code, Codex, Cursor, or...
View ToolClaude Code
Anthropic's agentic coding CLI. Runs in your terminal, edits files autonomously, spawns sub-agents, and maintains memory...
View Tool
Codeburn
Interactive TUI dashboard that shows exactly where your Claude Code and Cursor tokens are going, in real time.
View Tool
Claude Opus 4.7
Anthropic's flagship reasoning model. Best-in-class for coding, long-context analysis, and agentic workflows. 1M token c...
View ToolRelated Videos
Open Design: Turn Websites into Design Assets for Cursor & Claude Code
Open Design: Open-Source n8n App That Turns Any Website into a Brand Kit, Design System, HTML + Images The video introduces Open Design, an MIT-licensed full-stack template that combines AI and n8n a
Nimbalyst: The Open-Source Visual Workspace for Building with Codex and Claude Code
Nimbalyst Demo: A Visual Workspace for Codex + Claude Code with Kanban, Plans, and AI Commits Try it: https://nimbalyst.com/ Star Repo Here: https://github.com/Nimbalyst/nimbalyst This video demos N
Composio: Connect OpenClaw & Claude Code to 1,000+ Apps via CLI
Composio: Connect AI Agents to 1,000+ Apps via CLI (Gmail, Google Docs/Sheets, Hacker News Workflows) Check out Composio here: http://dashboard.composio.dev/?utm_source=Youtube&utm_channel=0426&utm_
Related Posts
Claude Outages Are a Workflow Design Problem
Claude outages and 529 overloads expose whether your AI coding workflow has checkpoints, receipts, model-switch paths, a...
Claude Opus 4.8 Is an Agent Honesty Release
Claude Opus 4.8 looks like a benchmark bump, but the developer story is better honesty, dynamic workflows, and effort co...
Anthropic Sonnet 4.5 in Claude Code
Anthropic's Claude Sonnet 4.5 isn't just another model increment. The company claims they've observed it maintaining foc...
ChatGPT Work vs Claude Cowork 2026 - Complete Comparison
OpenAI launched ChatGPT Work to compete with Claude Cowork. Here is how they compare on features, pricing, integrations,...
Vera Shows Agent Safety Needs Test Oracles, Not Vibes
A new Vera paper tests Codex, Claude Code, OpenClaw, and Hermes with executable safety cases. The useful lesson is not p...
Bun Rewrites 535K Lines of Zig to Rust in 11 Days Using Claude
The Bun runtime completed an AI-assisted rewrite from Zig to Rust, fixing memory safety issues and improving performance...
