agent-development

agent-development is a skill for Claude Code from majiayu000/claude-skill-registry. It costs 104 tokens per session (1,492 once invoked), scanned A, original, MIT.

A guide and template for creating autonomous coding agents as Markdown files with settings, instructions, tools, and example triggers.

In plain words
What is it for?
Use it to create agent files, write system prompts, define triggering examples, configure tools, and validate the result.
Why use it?
It removes the guesswork from structuring an agent and checking whether its configuration follows the expected format.

Skill for Claude Code

Written for Claude Code: PreToolUse hook event. Also seen: mentions subagents; mentions Claude Code.

Good fit Use it to create agent files, write system prompts, define triggering examples, configure tools, and validate the result.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/majiayu000/claude-skill-registry/agent-development-oshankhz-cc-swiss-knife-3
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add majiayu000/claude-skill-registry --skill agent-development-oshankhz-cc-swiss-knife-3
Clone the repo
git clone --depth 1 https://github.com/majiayu000/claude-skill-registry

Made for: Claude Code.

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 agent-development

README.md
[![agentmods](https://agentmods.dev/badge/skills/majiayu000/claude-skill-registry/agent-development-oshankhz-cc-swiss-knife-3/github.svg)](https://agentmods.dev/skills/majiayu000/claude-skill-registry/agent-development-oshankhz-cc-swiss-knife-3)
Your own site
<a href="https://agentmods.dev/skills/majiayu000/claude-skill-registry/agent-development-oshankhz-cc-swiss-knife-3"><img src="https://agentmods.dev/badge/skills/majiayu000/claude-skill-registry/agent-development-oshankhz-cc-swiss-knife-3/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for agent-development

Your own site · 80×15
<a href="https://agentmods.dev/skills/majiayu000/claude-skill-registry/agent-development-oshankhz-cc-swiss-knife-3"><img src="https://agentmods.dev/badge/skills/majiayu000/claude-skill-registry/agent-development-oshankhz-cc-swiss-knife-3.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 104 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,492 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found 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 $0.00104 $0.01492
Opus 5 $0.00052 $0.00746
Sonnet 5 $0.00021 $0.00298
Haiku 4.5 $0.00010 $0.00149

Measured 9d ago against content hash e7cd80785283, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

agent-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 9d 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.

skills/agent/agent-development-oshankhz-cc-swiss-knife-3/SKILL.md · 168 lines

How it starts

The opening of the file, as written. The whole thing — 168 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agent Development for Claude Code Plugins

Agents are autonomous markdown files with YAML frontmatter that handle multi-step tasks independently. Agents are for autonomous work; commands are for user-initiated actions.

Workflow

  1. Define agent purpose and triggering conditions
  2. Create agents/agent-name.md with frontmatter + system prompt body
  3. Include 2-4 <example> blocks in description
  4. Validate structure (see constraints below)
  5. Test triggering with real scenarios
  6. If validation fails: check error recovery table, fix, re-validate

Agent File Template

---
name: agent-identifier
description: Use this agent when [triggering conditions]. Examples:

<example>
Context: [Situation]
user: "[Request]"
assistant: "[Response before triggering]"
<commentary>[Why this agent triggers]</commentary>
</example>

model: inherit
color: blue
tools: ["Read", "Write", "Grep"]
---

You are [role] specializing in [domain].

**Your Core Responsibilities:**
1. [Primary task]
2. [Secondary task]

**Process:**
1. [Step 1]
2. [Step 2]

**Output Format:**
[What to return and how]

**Edge Cases:**
- [Case]: [How to handle]

Frontmatter Reference

Field Required Format Constraints
name Yes lowercase-hyphens 3-50 chars, start/end alphanumeric, no underscores
description Yes Text + <example> blocks 10-5000 chars, must include triggering conditions
model Yes inherit|sonnet|opus|haiku Use inherit unless specific need
color Yes blue|cyan|green|yellow|magenta|red Distinct per plugin
tools No Array of tool names Least-privilege principle; default: all tools
hooks No Array of hook configs See hooks section
disallowedTools No Array with Task(AgentName) Prevents specific agents from running

Color conventions: blue/cyan = analysis/review, green = success, yellow = validation, red = security, magenta = creative.

Read the full file on GitHub · 168 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 9d ago First seen · 168 lines · 104 tokens per session scan A e7cd80785283

Subscribe to this mod's changes

agent-development is a skill published in the GitHub repository majiayu000/claude-skill-registry (606 stars, last pushed today), licensed MIT. It adds 104 tokens to every session and 1,492 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.