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/oborchers/fractional-ctoWrote 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/oborchers/fractional-cto/api-design-principles)<a href="https://agentmods.dev/plugins/oborchers/fractional-cto/api-design-principles"><img src="https://agentmods.dev/badge/plugins/oborchers/fractional-cto/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/oborchers/fractional-cto/api-design-principles"><img src="https://agentmods.dev/badge/plugins/oborchers/fractional-cto/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",
"version": "1.0.1",
"description": "Research-backed, opinionated guidance for designing world-class RESTful APIs \u2014 routes, naming, errors, auth, caching, webhooks, and more, distilled from Stripe, GitHub, Twilio, Shopify, Google, and Microsoft",
"author": {
"name": "Dr. Oliver Borchers"
},
"repository": "https://github.com/oborchers/fractional-cto",
"license": "MIT",
"keywords": [
"api",
"rest",
"design",
"routes",
"errors",
"auth",
"caching",
"webhooks",
"pagination",
"versioning",
"security",
"documentation"
]
}
What it installs
The manifest is a name and a version. 13 skills, 1 command, 1 agent travel with it, and installing the plugin installs all of them — 1,240 tokens a session between them. Each is measured on its own page, and each can be installed alone.
- Skill errors-and-status-codes A 80 tokens
- Skill http-methods A 73 tokens
- Skill prefixed-ids A 69 tokens
- Skill rate-limiting-and-security A 79 tokens
- Skill routes-and-naming A 81 tokens
- Skill versioning-and-evolution A 72 tokens
- Skill webhooks-and-events A 73 tokens
- Skill auth-and-api-keys A 82 tokens
- Skill response-design-and-pagination A 68 tokens
- Skill advanced-patterns A 81 tokens
- Skill caching-and-performance A 76 tokens
- Skill documentation-and-dx A 75 tokens
- Skill using-api-principles A 73 tokens
- Command api-review A 16 tokens
- Agent api-design-reviewer A 242 tokens
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 · 25 lines scan A 8aed359926c6
api-design-principles is a plugin published in the GitHub repository oborchers/fractional-cto (33 stars, last pushed 12d ago), 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.
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