/claude-code-bash-patterns

name: claude-code-bash-patterns
description: Claude Code Bash tool patterns with hooks, automation, git workflows. Use for PreToolUse hooks, command chaining, CLI orchestration, custom commands, or encountering bash permissions, command failures, security guards, hook configurations.
license: MIT
metadata:
  version: "2.0.0"
  last_verified: "2025-11-18"
  production_tested: true
  token_savings: "55%"
  errors_prevented: 12
  templates_included: 5
  references_included: 5

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 ✅

1. **Use && for sequential dependencies** (not semicolons) 2. **Quote paths with spaces** (`cd "path with spaces"`) 3. **Check environment before destructive ops** (rm, git push --force) 4. **Use specialized tools first** (Read, Grep, Glob before Bash) 5. **Set timeouts for long operations** (up to 10 minutes) 6. **Validate inputs** before passing to shell commands 7. **Use hooks for repeated patterns** (logging, validation) 8. **Maintain session state** (export variables once) 9. **Handle errors explicitly** (check exit codes) 10. **Document custom commands** in .claude/commands/

Never Do ❌

1. **Never use ; for dependent commands** (use &&) 2. **Never skip quoting paths** with spaces 3. **Never run rm -rf without confirmation** 4. **Never expose secrets** in command output 5. **Never ignore timeout limits** (max 10 min) 6. **Never use bash for file operations** when specialized tools exist 7. **Never chain with newlines** (use && or ; explicitly) 8. **Never force-push to main** without explicit user request 9. **Never skip hooks** (--no-verify) without user request 10. **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 i