api-designer

api-designer is a skill for Claude Code, Codex from AutumnsGrove/ClaudeSkills. It costs 77 tokens per session (3,455 once invoked), scanned A, original, no licence file.

An API design and documentation guide for REST APIs, which use web URLs and requests, and GraphQL APIs, which let clients request specific data. It covers OpenAPI/Swagger specifications, access control, and versioning.

In plain words
What is it for?
Use it to write API specifications, design REST endpoints or GraphQL schemas, plan authentication and authorization, and choose API versioning approaches.
Why use it?
It helps turn API ideas into clear, documented interfaces and reduces confusion about endpoints, data schemas, authentication, and changes between versions.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit Use it to write API specifications, design REST endpoints or GraphQL schemas, plan authentication and authorization, and choose API versioning approaches.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/autumnsgrove/claudeskills/api-designer
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.

Any agent
npx skills add AutumnsGrove/ClaudeSkills --skill api-designer
Clone the repo
git clone --depth 1 https://github.com/AutumnsGrove/ClaudeSkills

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for api-designer

README.md
[![agentmods](https://agentmods.dev/badge/skills/autumnsgrove/claudeskills/api-designer/github.svg)](https://agentmods.dev/skills/autumnsgrove/claudeskills/api-designer)
Your own site
<a href="https://agentmods.dev/skills/autumnsgrove/claudeskills/api-designer"><img src="https://agentmods.dev/badge/skills/autumnsgrove/claudeskills/api-designer/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.

agentmods 80×15 button for api-designer

Your own site · 80×15
<a href="https://agentmods.dev/skills/autumnsgrove/claudeskills/api-designer"><img src="https://agentmods.dev/badge/skills/autumnsgrove/claudeskills/api-designer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 77 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,455 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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 5.1 $0.00077 $0.03455
Opus 5 $0.00039 $0.01728
Sonnet 5 $0.00015 $0.00691
Haiku 4.5 $0.00008 $0.00346

Measured 9d ago against content hash 6db6374d77b6, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

api-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 9d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/api_helper.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

api-designer/SKILL.md · 559 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Files

What ships with it

8 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.

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. 9d ago First seen · 559 lines · 77 tokens per session scan A 6db6374d77b6

Subscribe to this mod's changes

api-designer is a skill published in the GitHub repository AutumnsGrove/ClaudeSkills (30 stars, last pushed 10mo ago), with no licence file. It adds 77 tokens to every session and 3,455 once invoked, about $0.0004 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 2026-08-30.

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