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 skills add komluk/scaffolding --skill api-designgit clone --depth 1 https://github.com/komluk/scaffoldingWrote 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/komluk/scaffolding/api-design)<a href="https://agentmods.dev/skills/komluk/scaffolding/api-design"><img src="https://agentmods.dev/badge/skills/komluk/scaffolding/api-design/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/skills/komluk/scaffolding/api-design"><img src="https://agentmods.dev/badge/skills/komluk/scaffolding/api-design.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00068 | $0.01280 |
| Opus 5.5 | $0.00027 | $0.00512 |
| Sonnet 5.5 | $0.00014 | $0.00256 |
| Haiku 4.5 | $0.00007 | $0.00128 |
Grade A, and why
api-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 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.
How it starts
The opening of the file, as written. The whole thing — 208 lines — stays where its author put it; the contents beside it link to each section on GitHub.
API Design Skill
Purpose
Standards and best practices for designing RESTful APIs.
Auto-Invoke Triggers
- Designing new API endpoints
- Creating OpenAPI documentation
- Implementing API versioning
- Designing error responses
- Implementing pagination
REST API Principles
Resource Naming
- Use nouns, not verbs:
/usersnot/getUsers - Use plural nouns:
/usersnot/user - Use kebab-case:
/user-profilesnot/userProfiles - Use lowercase only
- Max 2 levels nesting:
/users/{id}/posts
URL Patterns
| Pattern | Example | Use Case |
|---|---|---|
| Collection | /users |
List resources |
| Item | /users/{id} |
Single resource |
| Nested | /users/{id}/posts |
Related resources |
| Action | /users/{id}/activate |
Non-CRUD operations |
HTTP Methods
| Method | Purpose | Idempotent | Safe | Has Body |
|---|---|---|---|---|
| GET | Read | Yes | Yes | No |
| POST | Create | No | No | Yes |
| PUT | Replace entire resource | Yes | No | Yes |
| PATCH | Partial update | No | No | Yes |
| DELETE | Remove | Yes | No | No |
Method Selection Rules
- GET for retrieval only, never modify state
- POST for creation, returns 201 with Location header
- PUT replaces entire resource, all fields required
- PATCH for partial updates, only changed fields
- DELETE returns 204 No Content on success
Status Codes
Success (2xx)
| Code | Use Case |
|---|---|
| 200 OK | GET, PUT, PATCH success |
| 201 Created | POST success (+ Location header) |
| 204 No Content | DELETE success |
Client Error (4xx)
| Code | Use Case |
|---|---|
| 400 Bad Request | Malformed request, validation error |
| 401 Unauthorized | Authentication required |
| 403 Forbidden | Authenticated but no permission |
| 404 Not Found | Resource doesn't exist |
| 409 Conflict | Resource state conflict |
| 422 Unprocessable Entity | Semantic validation error |
| 429 Too Many Requests | Rate limit exceeded |
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 · 208 lines · 68 tokens per session scan A 4c23c8cc6ccd
api-design is a skill published in the GitHub repository komluk/scaffolding (15 stars, last pushed 2d ago), licensed MIT. It adds 68 tokens to every session and 1,280 once invoked, about $0.0003 per session on Opus 5.5. 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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