Borrowing it
Nothing to install: this file belongs to Erikote04/Swift-API-Design-Guidelines-Agent-Skill. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/Erikote04/Swift-API-Design-Guidelines-Agent-Skill/main/.github/copilot-instructions.mdgit clone --depth 1 https://github.com/Erikote04/Swift-API-Design-Guidelines-Agent-SkillWrote 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/instructions/erikote04/swift-api-design-guidelines-agent-skill/copilot-instructions)<a href="https://agentmods.dev/instructions/erikote04/swift-api-design-guidelines-agent-skill/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/erikote04/swift-api-design-guidelines-agent-skill/copilot-instructions/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/instructions/erikote04/swift-api-design-guidelines-agent-skill/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/erikote04/swift-api-design-guidelines-agent-skill/copilot-instructions.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 | $0.00984 | $0.00984 |
| Opus 5.5 | $0.00394 | $0.00394 |
| Sonnet 5.5 | $0.00197 | $0.00197 |
| Haiku 4.5 | $0.00098 | $0.00098 |
Grade A, and why
Swift-API-Design-Guidelines-Agent-Skill copilot-instructions.md 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 2mo 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 — 78 lines — stays where its author put it; the contents beside it link to each section on GitHub.
GitHub Copilot Instructions: Agent Skills Expert (Swift API Design Guidelines)
Review changes as an Agent Skills expert, focusing on the Agent Skills open format specification and ensuring this repository stays a Swift API design-guidelines-focused, clarity-first, convention-aligned skill.
Core Agent Skills Principles
Format Compliance
SKILL.mdrequired: Every skill directory must contain aSKILL.mdwith YAML frontmatter.- YAML frontmatter requirements:
name: non-empty, <= 64 chars, lowercase letters/numbers/hyphens only.description: non-empty, <= 1024 chars, clearly states what the skill does and when to use it.
- Progressive disclosure: keep
SKILL.mdas the primary entrypoint; move deep dives intoswift-api-design-guidelines-skill/references/. - Filesystem-based design: content should be organized so agents can load only what they need (metadata -> instructions -> references).
Skill Content Organization (Progressive Disclosure)
Level 1: Metadata (always loaded)
- YAML frontmatter should be concise and trigger-relevant.
Level 2: Instructions (loaded when triggered)
swift-api-design-guidelines-skill/SKILL.mdbody should contain workflows, checklists, decision trees, and quick references.- Avoid turning
SKILL.mdinto an encyclopedia; prefer linking out to references.
Level 3: Resources (loaded as needed)
- Topic-specific guidance lives in
swift-api-design-guidelines-skill/references/*.md. - References should be linked from
SKILL.mdso agents discover them naturally.
Repository Constraints (Keep This Skill “On Mission”)
- Swift API design focus: prioritize naming, argument labels, terminology, documentation comments, and conventions.
- No architecture mandates: do not prescribe MVVM/MVC/VIPER/coordinators/routers or project folder structures.
- No tooling walkthroughs: avoid IDE/tool step-by-step instructions.
- Guideline fidelity: align recommendations with Swift API Design Guidelines semantics and point-of-use clarity.
- Pragmatic guidance: recommendations should be actionable and review-friendly, not theoretical.
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.
- 2mo ago First seen · 78 lines · 984 tokens per session scan A 01a7a86d9ad4
Swift-API-Design-Guidelines-Agent-Skill copilot-instructions.md is an instructions file published in the GitHub repository Erikote04/Swift-API-Design-Guidelines-Agent-Skill (33 stars, last pushed 8mo ago), licensed MIT. It adds 984 tokens to every session, about $0.0039 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.
Swift-API-Design-Guidelines-Agent-Skill copilot-instructions.md compared with instructions from other repositories
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|---|---|---|---|---|---|---|---|
| Swift-API-Design-Guidelines-Agent-Skill copilot-instructions.mdErikote04/Swift-API-Design-Guidelines-Agent-Skill | Instructions file | 33 | 8mo ago | MIT | A | 984 | GitHub Copilot |
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