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 agentmods add instructions/avdlee/xcode-build-optimization-agent-skill/copilot-instructionsgit clone --depth 1 https://github.com/AvdLee/Xcode-Build-Optimization-Agent-SkillWhat 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 | $0.00525 | $0.00525 |
| Opus 5 | $0.00262 | $0.00262 |
| Sonnet 5 | $0.00105 | $0.00105 |
| Haiku 4.5 | $0.00052 | $0.00052 |
Grade A, and why
Xcode-Build-Optimization-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 2d 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 — 70 lines — stays where its author put it; the contents beside it link to each section on GitHub.
GitHub Copilot Instructions: Xcode Build Optimization Skills
Review changes as an Agent Skills expert and Xcode build optimization reviewer.
Repository Mission
Keep this repository focused on:
- Xcode clean and incremental build benchmarking
- compile hotspot analysis
- build settings and scheme auditing
- build script and dependency-analysis guidance
- Swift Package Manager build overhead and module variant analysis
Do not turn the repository into general iOS architecture guidance or product documentation.
Agent Skill Requirements
- Every skill directory must contain a
SKILL.mdwith validnameanddescriptionfrontmatter. - Descriptions must state both what the skill does and when to use it.
- Keep
SKILL.mdconcise and delegate deeper material to one-level-deep reference files. - Reference files should be discoverable from the matching
SKILL.md.
Behavior Constraints
- Default to recommend-first behavior.
- Never introduce instructions that apply project, build-setting, or source changes without explicit developer approval.
- Preserve evidence-driven workflows: command used, build type, target or package affected, and measured impact.
- Prefer deterministic shell commands and structured artifacts over ad hoc prose.
Build Optimization Focus Areas
When reviewing changes, prioritize:
-
Benchmark correctness
- clean vs incremental builds are treated separately
- warm-up and repetition rules are explicit
- output artifacts are stored in
.build-benchmark/
-
Evidence quality
- recommendations cite timing summaries, script phases, compiler diagnostics, or dependency data
- estimated impact and confidence are separated from observed evidence
-
Apple-aligned guidance
- target dependencies and build order accuracy
- script input/output declarations and
.xcfilelistusage DEFINES_MODULE, module maps, and framework-qualified imports- explicit module dependency and module variant reduction guidance
- explicit type information and simpler expressions for Swift compile efficiency
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.
- 2d ago First seen · 70 lines · 525 tokens per session scan A a77d5d6d6c98
Xcode-Build-Optimization-Agent-Skill copilot-instructions.md is an instructions file published in the GitHub repository AvdLee/Xcode-Build-Optimization-Agent-Skill (1,212 stars, last pushed 20d ago), licensed MIT. It adds 525 tokens to every session, about $0.0026 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.
Other instructions, from other repositories
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Instructions for vermont42/iOS-Design-Agent-Skill, covering agent guidelines, in scope and out of scope.
AppClaw CLAUDE.md
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swift-architecture-skill CLAUDE.md
Instructions for efremidze/swift-architecture-skill, covering swift architecture skill, project structure, how the skill works and key conventions.
swift-architecture-skill AGENTS.md
Instructions for efremidze/swift-architecture-skill, covering agents guidelines for swift architecture skill, working with this repository, 1. understanding the skill, 2. modifying architecture playbooks and 3. testing and validation.
XcodeMCPWrapper AGENTS.md
Instructions for SoundBlaster/XcodeMCPWrapper, covering xcode mcp wrapper, project overview, the problem, the solution and architecture.
uikit-expert-skill AGENTS.md
Instructions for ivan-magda/uikit-expert-skill, covering agent guidelines for uikit expert skill, core principles, 1. uikit focus only, 2. no code formatting or linting and 3. no architectural opinions.