Claude Code Bash Patterns

Status: Production Ready ✅ | Last Verified: 2025-11-18

Quick Start

Basic Command

ls -la

Command Chaining

bun install && bun run build && bun test

Hooks

Create .claude-hook-pretooluse.sh :

#!/usr/bin/env bash

PreToolUse hook - runs before every Bash command

echo "Running: $1"

Load references/hooks-examples.md for complete hook patterns.

The Five Core Patterns

1. Sequential Operations (&&)

Use when: Each command depends on previous success

git add . && git commit -m "message" && git push

Why: Stops chain if any command fails

2. Parallel Operations (Multiple tool calls)

Use when: Commands are independent

Message with multiple Bash tool calls in parallel

Load references/cli-tool-integration.md for parallel patterns.

3. Session Persistence

Use when: Need to maintain state across commands

Set environment variable

export API_KEY="sk-..."

Use in later commands (same session)

curl -H "Authorization: Bearer $API_KEY" api.example.com

4. Background Processes

Use when: Long-running tasks

npm run dev &

Get PID with $!

5. Hooks for Automation

Use when: Need pre/post command logic

Load references/hooks-examples.md for all hook types.

Critical Rules

Always Do ✅

• Use && for sequential dependencies (not semicolons)

• Quote paths with spaces (cd "path with spaces" )

• Check environment before destructive ops (rm, git push --force)

• Use specialized tools first (Read, Grep, Glob before Bash)

• Set timeouts for long operations (up to 10 minutes)

• Validate inputs before passing to shell commands

• Use hooks for repeated patterns (logging, validation)

• Maintain session state (export variables once)

• Handle errors explicitly (check exit codes)

• Document custom commands in .claude/commands/

Never Do ❌

• Never use ; for dependent commands (use &&)

• Never skip quoting paths with spaces

• Never run rm -rf without confirmation

• Never expose secrets in command output

• Never ignore timeout limits (max 10 min)

• Never use bash for file operations when specialized tools exist

• Never chain with newlines (use && or ; explicitly)

• Never force-push to main without explicit user request

• Never skip hooks (--no-verify) without user request

• Never use interactive commands (git rebase -i, git add -i)

Git Workflows

Basic Commit

git add . && git commit -m "feat: add feature"

Commit with Testing

npm test && git add . && git commit -m "fix: bug fix" && git push

Pull Request

git checkout -b feature/new && git add . && git commit -m "feat: new feature" && git push -u origin feature/new

Load references/git-workflows.md for complete workflows including:

• Feature branch workflow

• PR creation automation

• Commit message conventions

• Pre-commit validation

Hooks: Advanced Automation

PreToolUse Hook

.claude-hook-pretooluse.sh :

#!/usr/bin/env bash COMMAND="$1"

Log all commands

echo "[$(date)] Running: $COMMAND" >> ~/claude-commands.log

Block dangerous patterns

if [[ "$COMMAND" =~ rm\ -rf\ / ]]; then echo "❌ Blocked dangerous command" exit 1 fi

Hook Types

• pretooluse - Before every Bash command

• stop - Before conversation ends

• user-prompt-submit - After user submits message

Load references/hooks-examples.md for all hook types and examples.

CLI Tool Integration

npm/bun

bun install && bun run build

wrangler (Cloudflare)

bunx wrangler deploy

gh (GitHub CLI)

gh pr create --title "Fix bug" --body "Description"

Load references/cli-tool-integration.md for complete tool patterns.

Custom Commands

Create .claude/commands/deploy.md :

description: Deploy to production

Run these steps:

1. Run tests: npm test
2. Build: npm run build
3. Deploy: wrangler deploy

User can invoke with: /deploy

Load templates/custom-command-template.md for template.

Security

Allowlisting Tools

settings.json :

{ "dangerousCommandsAllowList": [ "git push --force" ] }

Secrets Management

✅ Good: Use environment variables

export API_KEY="$SECURE_VALUE"

❌ Bad: Hardcode secrets

curl -H "Authorization: Bearer sk-abc123..."

Load references/security-best-practices.md for complete security guide.

Common Use Cases

Use Case 1: Test Before Commit

npm test && git add . && git commit -m "message"

Use Case 2: Deploy with Validation

npm run lint && npm test && npm run build && bunx wrangler deploy

Use Case 3: Multi-Repo Operations

cd repo1 && git pull && cd ../repo2 && git pull

Use Case 4: Background Process

npm run dev &

Load references/cli-tool-integration.md for more patterns.

Troubleshooting

Issue: Command times out

Solution: Increase timeout or use background mode

Background mode

npm run dev &

Issue: Path with spaces fails

Solution: Quote the path

cd "path with spaces/file.txt"

Issue: Hook blocks command

Solution: Check hook logic in .claude-hook-pretooluse.sh

Load references/troubleshooting-guide.md for all issues.

When to Load References

Load references/git-workflows.md when:

• Setting up git automation

• Creating PRs programmatically

• Need commit message conventions

• Want pre-commit validation patterns

Load references/hooks-examples.md when:

• Creating custom hooks

• Need hook templates

• Want validation patterns

• Implementing logging/security

Load references/cli-tool-integration.md when:

• Orchestrating multiple CLI tools

• Need tool-specific patterns

• Want parallel execution examples

• Troubleshooting tool integration

Load references/security-best-practices.md when:

• Configuring security guards

• Setting up allowlisting

• Managing secrets

• Preventing dangerous operations

Load references/troubleshooting-guide.md when:

• Debugging command failures

• Encountering timeouts

• Hooks behaving unexpectedly

• Session state issues

Using Bundled Resources

References (references/)

• git-workflows.md - Complete git automation patterns

• hooks-examples.md - All hook types with examples

• cli-tool-integration.md - Tool orchestration patterns

• security-best-practices.md - Security configuration guide

• troubleshooting-guide.md - Common issues and solutions

Templates (templates/)

• custom-command-template.md - Custom command template

• settings.json - Security settings example

• .envrc.example - Environment variables example

• github-workflow.yml - GitHub Actions integration

• dangerous-commands.json - Dangerous patterns list

Examples

Feature Development Workflow

git checkout -b feature/oauth &&
npm test &&
git add . &&
git commit -m "feat(auth): add OAuth support" &&
git push -u origin feature/oauth

CI/CD Pipeline

npm run lint &&
npm test &&
npm run build &&
bunx wrangler deploy

Multi-Project Update

cd project1 && bun install && cd ../project2 && bun install

Official Documentation

• Claude Code Bash Tool: https://docs.claude.com/en/docs/claude-code/tools

• Hooks: https://docs.claude.com/en/docs/claude-code/hooks

• Custom Commands: https://docs.claude.com/en/docs/claude-code/custom-commands

Questions? Issues?

• Check references/troubleshooting-guide.md for common issues

• Review references/git-workflows.md for git patterns

• See references/hooks-examples.md for automation

• Load references/security-best-practices.md for security