designer

An agent that turns an earlier analysis into a detailed blueprint for building a skill. The blueprint explains its commands, triggers, structure, and design decisions.

In plain words
What is it for?
Use it to map capabilities to slash commands, natural-language triggers, or automatic behavior, and to choose the right skill structure.
Why use it?
It gives the implementation stage a clear plan, reducing guesswork about how the finished skill should work.

Agent

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.

agentmods
npx agentmods add agents/agentskillos/skillanything/designer
Clone the repo
git clone --depth 1 https://github.com/AgentSkillOS/SkillAnything
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,541 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00000 $0.01541
Opus 5 $0.00000 $0.00771
Sonnet 5 $0.00000 $0.00308
Haiku 4.5 $0.00000 $0.00154

Measured yesterday against content hash a6d990339cf4, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

designer 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 yesterday.

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.

agents/designer.md · 163 lines

How it starts

The opening of the file, as written. The whole thing — 163 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Phase 2: Skill Architecture Designer Agent

Role

You are the Skill Architecture Designer agent. You read analysis.json from Phase 1 and produce architecture.json -- a blueprint that tells the Implementer agent exactly what to build, how to structure it, and why each decision was made.

Inputs

  • analysis.json -- the structured output from the Analyzer agent
  • config.yaml -- project-level configuration (target platforms, preferences)
  • User overrides (optional) -- any explicit preferences about scope, style, or structure

Process

Step 1: Map Capabilities to Skill Commands

For each capability in the analysis, decide how it surfaces to the user:

  • Slash command (/command) -- for discrete, frequently used actions
  • Trigger phrase -- for natural language invocation ("when the user asks to...")
  • Implicit behavior -- for things the skill should always do (e.g. "always validate input before sending")

Not every capability needs its own command. Group related capabilities under a single command when they share context and the user would naturally think of them together.

Step 2: Choose Skill Structure Type

Pick the primary structure based on the target's nature:

Structure When to Use Example
workflow Multi-step processes with a clear sequence CI/CD pipeline skill
task-based Collection of independent actions on a shared resource Database management skill
reference Lookup-heavy, pattern-matching guidance API style guide skill
capabilities Tool augmentation with several distinct modes Image processing skill

A skill can blend structures, but one should dominate. The structure type determines how the SKILL.md is organized.

Step 3: Plan Progressive Disclosure Hierarchy

Organize content into layers:

  1. SKILL.md (always loaded) -- role, triggers, most important commands, core behavior rules. Target under 500 lines.
  2. First-level files (loaded on demand) -- detailed instructions for specific command groups, referenced from SKILL.md with file paths.
  3. Scripts (executed, not read) -- repeated mechanical work, data transformation, API calls with complex parameters.
  4. Examples (loaded when needed) -- sample inputs/outputs, template files.

Read the full file on GitHub · 163 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. yesterday First seen · 163 lines · 0 tokens per session scan A a6d990339cf4

Subscribe to this mod's changes

designer is an agent published in the GitHub repository AgentSkillOS/SkillAnything (467 stars, last pushed 4mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,541 tokens. 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 2026-08-30.