Command Creation Skill

This skill helps create production-ready custom slash commands following Anthropic's official specifications.

What is a Slash Command?

A slash command is a user-invoked reusable prompt stored as a Markdown file. Unlike skills (model-invoked) or agents (complex AI assistants), slash commands are:

• User-triggered: Explicitly invoked with /command-name
• Template-based: Expand to prompts with placeholders
• Lightweight: Simple Markdown files with optional frontmatter
• Quick access: Fast way to reuse common instructions

Commands vs Skills vs Agents

Feature	Command	Skill	Agent
Invocation	User (/name)	Model (automatic)	User or Task tool
Complexity	Simple prompt template	Capability with logic	Full AI assistant
Arguments	Yes ($1, $2, $ARGUMENTS)	N/A	N/A
File access	Yes (@file)	Via tools	Via tools
Bash exec	Yes (!command)	Via tools	Via tools
Use case	Quick prompts, workflows	Autonomous features	Domain expertise

When to use Commands: Reusable prompts, quick text expansion, parametrized instructions, file processing workflows

Command Structure

Basic Command (Prompt only)

Please review this code for security vulnerabilities and provide
specific recommendations for improvement.

File: .claude/commands/security-review.md Usage: /security-review

Command with Frontmatter

---
description: Review code for security vulnerabilities with OWASP focus
argument-hint: [file-path] [--strict]
allowed-tools: Read, Grep, Glob
model: opus
disable-model-invocation: false
---

Please perform a comprehensive security audit of the codebase, focusing on:
- OWASP Top 10 vulnerabilities
- Authentication and authorization issues
- Input validation and sanitization
- Secrets exposure

Frontmatter Fields

All frontmatter fields are optional.

description

Brief explanation shown in /help and for SlashCommand tool.

description: Generate comprehensive API documentation from OpenAPI spec

Best practices:

• 1 sentence, concise
• Describe what it does, not how
• Include key features

argument-hint

Expected arguments for autocomplete and help.

argument-hint: <endpoint-url> [--format json|yaml]
argument-hint: [file-pattern]
argument-hint: <branch-name>

Syntax conventions:

• <required> - Required argument
• [optional] - Optional argument
• | - Choice between options

allowed-tools

Restrict which tools the command can use.

allowed-tools: Read, Write, Grep, Glob
allowed-tools: Bash(git:*), Bash(npm:*)
allowed-tools: Read, WebFetch

Why restrict:

• Security: Prevent dangerous operations
• Focus: Command only needs specific tools
• Safety: Avoid accidental file modifications

model

Override the model for this command.

model: opus      # Complex reasoning
model: sonnet    # Balanced (default)
model: haiku     # Fast, simple tasks

disable-model-invocation

Prevent SlashCommand tool from invoking this command.

disable-model-invocation: true   # Only user can invoke
disable-model-invocation: false  # Claude can invoke (default)

Use cases:

• Private commands for personal use only
• Commands with dangerous operations
• Commands requiring user confirmation

Argument Handling

$ARGUMENTS

Captures all passed arguments as a single value.

Please analyze the following: $ARGUMENTS

Usage:

/analyze-text This is some text to analyze

Expands to:

Please analyze the following: This is some text to analyze

$1, $2, $3, ... (Positional Arguments)

Access individual arguments by position.

Compare $1 with $2 and explain the differences in $3 format.

Usage:

/compare file1.py file2.py detailed

Expands to:

Compare file1.py with file2.py and explain the differences in detailed format.

Default Values

Provide defaults for missing arguments.

Run tests in ${1:-development} environment with ${2:-verbose} output.

Usage:

/run-tests

Expands to:

Run tests in development environment with verbose output.

Usage with arguments:

/run-tests production quiet

Expands to:

Run tests in production environment with quiet output.

Combining Arguments

---
argument-hint: <action> <target> [options]
---

Execute $1 on $2 with options: $3
Fallback environment: ${3:-default}
All arguments: $ARGUMENTS

File References

@file Syntax

Include file contents in the prompt.

Please review this code:

@src/api/users.py

Focus on error handling and security.

When invoked, Claude reads src/api/users.py and includes its contents.

Multiple Files

Compare these two implementations:

**Old version:**
@src/legacy/auth.py

**New version:**
@src/current/auth.py

Highlight improvements and potential issues.

File Arguments

Review the file: @$1

And compare with: @$2

Usage:

/compare-files old-code.py new-code.py

File Patterns (with Glob)

Analyze all TypeScript files in the components directory.

Use the Glob tool to find files matching: src/components/**/*.tsx

Bash Execution

! Prefix for Bash Commands

Execute bash commands and include output.

---
allowed-tools: Bash(git:*), Bash(npm:*)
---

Check the current git status:

!git status

And list recent commits:

!git log --oneline -5

Security requirement: Must declare allowed bash commands in frontmatter.

allowed-tools: Bash(git:*), Bash(npm:*), Bash(docker:*)

Bash with Arguments

---
allowed-tools: Bash(git:*)
---

Show git log for branch: $1

!git log origin/$1..HEAD --oneline

Usage:

/branch-diff main

Command Chaining

---
allowed-tools: Bash(npm:*), Bash(git:*)
---

Run the following commands:

!npm run test
!npm run build
!git status

Extended Thinking

Commands can trigger extended thinking by including extended thinking keywords.

---
description: Analyze architectural implications of a design decision
---

Please analyze this architectural decision with extended thinking:

$ARGUMENTS

Consider:
- Long-term implications
- Alternative approaches
- Trade-offs and risks

Presence of "extended thinking" in the command triggers extended thinking mode.

File Organization

Project Commands (Shared with Team)

.claude/commands/
├── development/
│   ├── start-dev.md
│   ├── run-tests.md
│   └── build-prod.md
├── git/
│   ├── sync-main.md
│   └── cleanup-branches.md
└── review.md

Appears as:

• /start-dev (project:development)
• /run-tests (project:development)
• /sync-main (project:git)
• /review (project)

Personal Commands (Cross-Project)

~/.claude/commands/
├── personal/
│   ├── daily-standup.md
│   └── task-summary.md
└── notes.md

Appears as:

• /daily-standup (user:personal)
• /task-summary (user:personal)
• /notes (user)

Namespacing

Subdirectories organize commands but don't affect command names.

.claude/commands/api/create-endpoint.md

Command: /create-endpoint (not /api/create-endpoint) Shown as: /create-endpoint (project:api)

Conflict resolution: Project-level commands take precedence over user-level when names match.

Command Patterns

Code Review Command

---
description: Comprehensive code review focusing on quality and maintainability
argument-hint: [file-pattern]
allowed-tools: Read, Grep, Glob
model: opus
---

Perform a detailed code review covering:

1. **Code Quality**
   - Readability and clarity
   - Naming conventions
   - Code organization

2. **Best Practices**
   - Design patterns
   - Error handling
   - Performance considerations

3. **Security**
   - Input validation
   - Authentication/authorization
   - Data protection

$ARGUMENTS

Provide specific, actionable feedback with code examples.

Git Workflow Command

---
description: Complete feature branch workflow from creation to PR
argument-hint: <feature-name>
allowed-tools: Bash(git:*)
---

Execute feature branch workflow for: $1

!git checkout -b feature/$1
!git push -u origin feature/$1

Branch created: feature/$1

Next steps:
1. Make your changes
2. Commit with: /commit-feature $1
3. Create PR with: /create-pr $1

Test Runner Command

---
description: Run tests with coverage and generate report
allowed-tools: Bash(npm:*), Bash(pytest:*), Write
---

Running test suite with coverage...

!npm run test:coverage

Generate summary report:
- Test results
- Coverage percentage
- Failed tests details
- Recommendations for improving coverage

Documentation Generator Command

---
description: Generate API documentation from code
argument-hint: <directory-path>
allowed-tools: Read, Grep, Glob, Write
model: opus
---

Generate comprehensive API documentation for code in: $1

1. Scan for all public APIs, functions, and classes
2. Extract docstrings and type hints
3. Identify request/response formats
4. Document error cases
5. Generate examples

Output format: Markdown with clear hierarchy

File Comparison Command

---
description: Compare two files and highlight differences
argument-hint: <file1> <file2>
allowed-tools: Read
---

Compare these files and explain key differences:

**File 1: $1**
@$1

**File 2: $2**
@$2

Analysis:
1. Structural differences
2. Logic changes
3. Potential issues
4. Recommendations

Environment Setup Command

---
description: Set up development environment for this project
allowed-tools: Bash(npm:*), Bash(pip:*), Bash(cp:*), Read, Write
---

Setting up development environment...

!npm install

Copy environment template:
!cp .env.example .env

Please configure the following in .env:
- Database credentials
- API keys
- Service URLs

Verify setup:
!npm run verify-setup

Advanced Features

Conditional Logic in Prompts

---
argument-hint: <command> [--verbose]
---

Execute $1

${2:+Include detailed logging and timing information}
${2:-Use standard output}

Multi-Step Workflows

---
description: Complete deployment workflow
argument-hint: <environment>
allowed-tools: Bash(npm:*), Bash(git:*), Bash(ssh:*)
---

Deploying to: $1

Step 1: Run tests
!npm run test

Step 2: Build application
!npm run build

Step 3: Push to repository
!git push origin main

Step 4: Deploy to $1
!ssh deploy@$1-server "cd /app && git pull && pm2 restart app"

Deployment complete! Verify at: https://$1.example.com

Template Expansion

---
description: Create new React component
argument-hint: <ComponentName>
allowed-tools: Write
---

Create a new React component: $1

\`\`\`tsx
// src/components/$1.tsx
import React from 'react';

interface ${1}Props {
  // Define props
}

export const $1: React.FC<${1}Props> = (props) => {
  return (
    <div>
      {/* Component content */}
    </div>
  );
};
\`\`\`

\`\`\`tsx
// src/components/$1.test.tsx
import { render } from '@testing-library/react';
import { $1 } from './$1';

describe('$1', () => {
  it('renders correctly', () => {
    const { container } = render(<$1 />);
    expect(container).toBeInTheDocument();
  });
});
\`\`\`

Testing Your Command

1. Create command file:

   echo "Review this code: @\$1" > .claude/commands/quick-review.md
   

2. Test basic invocation:

   /quick-review src/app.py
   

3. Test with multiple arguments:

   /compare file1.py file2.py
   

4. Test bash execution:

   /git-status
   

5. Verify frontmatter:

   /help
   

   Confirm description appears correctly.

Common Mistakes to Avoid

❌ Undefined arguments

Review $1 and $2

Usage: /review file.py (only one argument) Result: $2 remains as literal text

✅ Default values

Review $1 ${2:+and compare with $2}

❌ Bash without tool permission

!git status

Missing: allowed-tools: Bash(git:*)

✅ Proper permissions

---
allowed-tools: Bash(git:*)
---

!git status

❌ Complex logic in commands

If $1 is production, then deploy carefully, otherwise...

Commands should be simple templates

✅ Use agents for complex logic

Use the deployment-agent to deploy to $1 environment

❌ Missing argument hints

---
description: Deploy application
---

Deploy to $1 with $2 configuration

✅ Clear argument hints

---
description: Deploy application
argument-hint: <environment> <config-file>
---

Deploy to $1 with $2 configuration

Command vs Skill vs Agent Decision

Need	Use
Quick text expansion	Command
Reusable prompt with args	Command
File reference workflow	Command
Bash execution workflow	Command
Autonomous capability	Skill
Complex domain expertise	Agent

Resources

Reference the examples directory for:

• Complete command definitions across different use cases
• Argument handling patterns
• Bash execution examples
• Multi-file workflow commands

---

Next Steps: After creating a command, test with various argument combinations, verify bash execution works as expected, and document usage in project README or command help text.