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 agentmods add skills/fusengine/agents/agent-designnpx skills add fusengine/agents --skill agent-designgit clone --depth 1 https://github.com/fusengine/agentsWrote 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/fusengine/agents/agent-design)<a href="https://agentmods.dev/skills/fusengine/agents/agent-design"><img src="https://agentmods.dev/badge/skills/fusengine/agents/agent-design.svg" alt="Measured on agentmods" 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 | $0.00028 | $0.00790 |
| Opus 5 | $0.00014 | $0.00395 |
| Sonnet 5 | $0.00006 | $0.00158 |
| Haiku 4.5 | $0.00003 | $0.00079 |
Grade A, and why
agent-design 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 2d 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.
How it starts
The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.
It routes to four references depending on the task: patterns.md for architecture choice (Single Agent, Orchestrator, Pipeline, Network, Supervisor, Hierarchical, Meta-Prompting), workflows.md for implementing APEX/TDD/Explore-Plan-Code/Review/Debug patterns inside an agent, templates.md for the full production frontmatter and Claude Code agent template, and anti-patterns.md for reviewing a design against common mistakes.
Agent Design
Skill for designing high-performance AI agents following 2025 patterns.
References
- patterns.md - Load when: choosing an agent architecture (Single Agent, Agent+Tools, Orchestrator, Pipeline, Network, Supervisor, Hierarchical, Meta-Prompting) or comparing their trade-offs
- workflows.md - Load when: implementing APEX, TDD, Explore-Plan-Code, Code Review, or Debugging workflows for an agent
- templates.md - Load when: writing a full agent definition (production frontmatter + sections) or a Claude Code agent template
- anti-patterns.md - Load when: reviewing an agent design for common mistakes (omniscient agent, implicit instructions, missing error handling)
Fundamental Distinction
Workflows vs Agents
| Type | Control | When to use |
|---|---|---|
| Workflow | Code orchestrates LLM | Predictable tasks, need for control |
| Agent | LLM directs its actions | Flexibility, adaptive decisions |
Golden rule: Start simple, add complexity if necessary.
Minimal Agent Structure
Agent:
identity: Who am I?
capabilities: What can I do?
tools: What tools do I have?
constraints: What are my limits?
workflow: How should I proceed?
What ships with it
4 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.
- 2d ago First seen · 93 lines · 28 tokens per session scan A 228fd8672e5e
agent-design is a skill published in the GitHub repository fusengine/agents (25 stars, last pushed yesterday), licensed MIT. It adds 28 tokens to every session and 790 once invoked, about $0.0001 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.
Other skills, from other repositories
radin-record
Log feedback, bugs, follow-ups, or ideas raised mid-session as structured backlog entries, so they survive past the conversation. Use for /radin-record, "log this to the backlog", "add as follow-up/bug/idea", "record what we just found", "note this for later", "add findings to backlog". Triggers even on vague asks…
radin-doctor
Check that radin's own install under /.claude is complete and its optional companion tools are reachable. Use for /radin-doctor, "check my radin install", "is radin installed correctly", "radin doctor", "verify radin install".
designing-interfaces
Creates a design system for software with a UI. Use when a project has a user interface and architecture is confirmed — whether creating from scratch or extracting patterns from existing code.
orchestrating-software-dev
Runs software development projects from idea to completion. Use when starting a software project, adding a feature, fixing a bug, or resuming an in-progress build.
managing-product
Extracts product requirements and produces a PRD. Use when a user wants to build software and needs to define what to build before architecture or implementation, when scoping an MVP, or when translating a vague idea into a buildable specification.
collecting-sources
Collects research sources with quality evaluation. Use when gathering or finding sources, building a source library, searching for academic papers, or performing RADAR assessment.