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.
git clone --depth 1 https://github.com/secondsky/claude-skillsWrote 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/plugins/secondsky/claude-skills/api-design-principles)<a href="https://agentmods.dev/plugins/secondsky/claude-skills/api-design-principles"><img src="https://agentmods.dev/badge/plugins/secondsky/claude-skills/api-design-principles/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/plugins/secondsky/claude-skills/api-design-principles"><img src="https://agentmods.dev/badge/plugins/secondsky/claude-skills/api-design-principles.svg" alt="Reviewed on agentmods" width="80" height="20"></a>Grade A, and why
api-design-principles 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.
What it actually says
{
"name": "api-design-principles",
"description": "Master REST and GraphQL API design principles to build intuitive, scalable, and maintainable APIs that delight developers. Use when designing new APIs, reviewing API specifications, or establishing API design standards.",
"version": "3.9.0",
"author": {
"name": "Claude Skills Maintainers",
"email": "[email protected]"
},
"license": "MIT",
"repository": "https://github.com/secondsky/claude-skills",
"keywords": [
"api-design-principles",
"api",
"design",
"principles",
"rest",
"graphql",
"endpoints",
"http",
"scalable",
"maintainable"
]
}
What it installs
The manifest is a name and a version. 1 skill travel with it, and installing the plugin installs all of them — 44 tokens a session between them. Each is measured on its own page, and each can be installed alone.
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 Changed b39c56591ed9
- 1mo ago First seen · 24 lines scan A 80f97d6d61fa
api-design-principles is a plugin published in the GitHub repository secondsky/claude-skills (231 stars, last pushed today), licensed MIT. Its token cost is not measured: this kind of file is read by the harness, not the model. 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.
Other plugins, from other repositories
chamnan
Preserves repository architecture, decisions, work state, and reusable engineering context across coding-agent sessions.
fewword
Context engineering plugin - tiered offloading, smart summaries, secret redaction, TOML/JSON config, command aliases, MCP allowlists, and self-diagnostics.
harnessay
Profile Claude Code and Codex transcripts: context budget reports, before/after comparisons, source evidence, and skill regression tests. Local-only, stdlib-only.
mcp-builder
Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools.
hyperfocus
ADHD-friendly output formatting. Restructures responses with evidence-based cognitive accessibility: chunking, visual hierarchy, front-loaded key points, and progressive disclosure.
ccx
Scratch-notebook context management for any project: per-thread STATE.md handoff docs with one-command create-or-resume (/ccx:start-thread), a compiled parallel-session-safe INDEX dashboard that recompiles itself on every STATE write (/ccx:save-state · /ccx:tidy-scratch), a Stop-hook freshness guard so working state…