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 $!

1. 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