command-development

command-development is a skill for Claude Code from basher83/lunar-claude. It costs 27 tokens per session (4,293 once invoked), scanned A, a copy of command-development, MIT.

Guidance for creating slash commands, which are reusable Markdown instructions that Claude runs when a user types a command such as `/command-name`.

In plain words
What is it for?
It is for defining command files, arguments, file references, shell context, configuration, and command organization.
Why use it?
It turns repeated prompts and workflows into consistent, quickly available actions.

Skill for Claude Code

Written for Claude Code: when-to-use in frontmatter. Also seen: reads .claude/ paths; names the AskUserQuestion tool; positional $N argument.

Runs only inside its plugin — its command needs a path that Claude Code sets for a plugin’s own hooks and for nothing else. Install the plugin, not this.

Part of the plugin-dev plugin — 7 skills, 5 commands, 3 agents shipped together

Good fit It is for defining command files, arguments, file references, shell context, configuration…

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.

Claude Code
/plugin marketplace add basher83/lunar-claude
Claude Code
/plugin install plugin-dev

Made for: Claude Code.

Or install plugin-dev, the plugin that ships this one along with the rest of its 7 skills, 5 commands, 3 agents.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for command-development

README.md
[![agentmods](https://agentmods.dev/badge/skills/basher83/lunar-claude/command-development.svg)](https://agentmods.dev/skills/basher83/lunar-claude/command-development)
Your own site
<a href="https://agentmods.dev/skills/basher83/lunar-claude/command-development"><img src="https://agentmods.dev/badge/skills/basher83/lunar-claude/command-development.svg" alt="Measured on agentmods" height="20"></a>
Per session 27 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,293 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 81% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00027 $0.04293
Opus 5 $0.00014 $0.02146
Sonnet 5 $0.00005 $0.00859
Haiku 4.5 $0.00003 $0.00429

Measured 3d ago against content hash 218e94ea7e09, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

command-development scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

81% identical to command-development — 106 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/meta/plugin-dev/skills/command-development/SKILL.md · 877 lines

How it starts

The opening of the file, as written. The whole thing — 877 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Command Development for Claude Code

Reference: See command-spec.md for the official specification.

Overview

Slash commands are frequently-used prompts defined as Markdown files that Claude executes during interactive sessions. Understanding command structure, frontmatter options, and dynamic features enables creating powerful, reusable workflows.

Key concepts:

  • Markdown file format for commands
  • YAML frontmatter for configuration
  • Dynamic arguments and file references
  • Bash execution for context
  • Command organization and namespacing

Command Basics

What is a Slash Command?

A slash command is a Markdown file containing a prompt that Claude executes when invoked. Commands provide:

  • Reusability: Define once, use repeatedly
  • Consistency: Standardize common workflows
  • Sharing: Distribute across team or projects
  • Efficiency: Quick access to complex prompts

Critical: Commands are Instructions FOR Claude

Commands are written for agent consumption, not human consumption.

When a user invokes /command-name, the command content becomes Claude's instructions. Write commands as directives TO Claude about what to do, not as messages TO the user.

Correct approach (instructions for Claude):

Review this code for security vulnerabilities including:
- SQL injection
- XSS attacks
- Authentication issues

Provide specific line numbers and severity ratings.

Incorrect approach (messages to user):

This command will review your code for security issues.
You'll receive a report with vulnerability details.

The first example tells Claude what to do. The second tells the user what will happen but doesn't instruct Claude. Always use the first approach.

Command Locations

Project commands (shared with team):

  • Location: .claude/commands/
  • Scope: Available in specific project
  • Label: Shown as "(project)" in /help
  • Use for: Team workflows, project-specific tasks

Read the full file on GitHub · 877 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 877 lines · 27 tokens per session scan A 218e94ea7e09

Subscribe to this mod's changes

command-development is a skill published in the GitHub repository basher83/lunar-claude (22 stars, last pushed yesterday), licensed MIT. It adds 27 tokens to every session and 4,293 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 81% identical to command-development, differing in 106 lines, and is treated as a copy.