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.
npx skills add smarks26/claude-plugin-template --skill agent-developmentgit clone --depth 1 https://github.com/smarks26/claude-plugin-templateWrote 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.
[](https://agentmods.dev/skills/smarks26/claude-plugin-template/agent-development)<a href="https://agentmods.dev/skills/smarks26/claude-plugin-template/agent-development"><img src="https://agentmods.dev/badge/skills/smarks26/claude-plugin-template/agent-development/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.
<a href="https://agentmods.dev/skills/smarks26/claude-plugin-template/agent-development"><img src="https://agentmods.dev/badge/skills/smarks26/claude-plugin-template/agent-development.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00080 | $0.02657 |
| Opus 5.5 | $0.00032 | $0.01063 |
| Sonnet 5.5 | $0.00016 | $0.00531 |
| Haiku 4.5 | $0.00008 | $0.00266 |
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 1mo 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.
This is a copy
100% identical to agent-development — 0 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.
How it starts
The opening of the file, as written. The whole thing — 402 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Agent Development for Claude Code Plugins
Overview
Agents are autonomous subprocesses that handle complex, multi-step tasks independently. Understanding agent structure, triggering conditions, and system prompt design enables creating powerful autonomous capabilities.
Key concepts:
- Agents are FOR autonomous work, commands are FOR user-initiated actions
- Markdown file format with YAML frontmatter
- Triggering via description field with examples
- System prompt defines agent behavior
- Model and color customization
Agent File Structure
Complete Format
---
name: agent-identifier
description: Use this agent when [triggering conditions]. Typical triggers include [scenario 1 in prose], [scenario 2 in prose], and [scenario 3 in prose]. See "When to invoke" in the agent body for worked scenarios.
model: inherit
color: blue
tools: ["Read", "Write", "Grep"]
---
You are [agent role description]...
## When to invoke
[Two to four representative scenarios written as prose, e.g.:]
- **[Scenario name].** [What the situation looks like and what the agent should do.]
- **[Scenario name].** [Same.]
**Your Core Responsibilities:**
1. [Responsibility 1]
2. [Responsibility 2]
**Analysis Process:**
[Step-by-step workflow]
**Output Format:**
[What to return]
Frontmatter Fields
name (required)
Agent identifier used for namespacing and invocation.
Format: lowercase, numbers, hyphens only Length: 3-50 characters Pattern: Must start and end with alphanumeric
Good examples:
code-reviewertest-generatorapi-docs-writersecurity-analyzer
Bad examples:
helper(too generic)-agent-(starts/ends with hyphen)my_agent(underscores not allowed)ag(too short, < 3 chars)
description (required)
Defines when Claude should trigger this agent. This is the most critical field — it is loaded into context whenever the agent is registered, so the harness can decide when to dispatch.
Must include:
- Triggering conditions ("Use this agent when...")
- A short prose summary of the typical trigger scenarios
- A pointer to a "When to invoke" section in the agent body for the detailed worked scenarios
What ships with it
6 files 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.
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.
- 1mo ago First seen · 402 lines · 80 tokens per session scan A 6a2826571320
agent-development is a skill published in the GitHub repository smarks26/claude-plugin-template (2 stars, last pushed 4mo ago), licensed MIT. It adds 80 tokens to every session and 2,657 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to agent-development, differing in 0 lines, and is treated as a copy.
Other skills, from other repositories
access
Manage who may drive telegram-topics sessions — view and edit the user allowlist. Use when the user asks to allow or remove a Telegram user, check who's allowed, or lock the channel down.
version-sentinel
Use when adding, bumping, or changing a dependency in package.json, requirements.txt, constraints.txt, pyproject.toml, Cargo.toml, .csproj, .fsproj, or .vbproj. Triggered automatically by version-sentinel's PreToolUse hook (where the host supports hooks) — this skill explains how to satisfy the block and record a…
personal-voice-capture
Use when a user wants an agent to learn, encode, or improve their personal writing voice as a reusable skill through source-text ingestion and iterative calibration edits.
compounded-author
Use this skill when you have just completed a non-trivial task (more than 3 tool calls, novel approach, recovery from a dead end) and are considering whether to save the procedure as a reusable skill via compounded; OR in RULE MODE when the user corrected your approach and the correction encodes a generalizable…
compounded-verifier
Use this skill ONLY when invoked as the skill-verifier subagent by compounded's Stop hook. This is the rubric for deciding whether a proposed skill should graduate to .verified or move to .rejected/ based on its replayability against a just-completed task. Do not invoke this skill in normal sessions.
compounded-typo-fixer
Use this skill when the user reports a typo in their codebase or documentation and asks for it to be fixed across the project, or when reviewing code and noticing a misspelled identifier, comment, or string that should be corrected consistently across all occurrences.