Xcode Build Optimization Agent Skills is a collection of agent skills that benchmarks and analyzes Xcode clean and incremental builds, compiler hotspots, project settings, and Swift Package Manager overhead. It is for iOS developers who want an AI coding agent to identify build-performance improvements and produce an optimization plan before changes are approved. The catalogue entries provide the skills, instructions, and plugin used for this workflow.
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 AvdLee/Xcode-Build-Optimization-Agent-Skill --skill xcode-compilation-analyzergit clone --depth 1 https://github.com/AvdLee/Xcode-Build-Optimization-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/skills/avdlee/xcode-build-optimization-agent-skill/xcode-compilation-analyzer)<a href="https://agentmods.dev/skills/avdlee/xcode-build-optimization-agent-skill/xcode-compilation-analyzer"><img src="https://agentmods.dev/badge/skills/avdlee/xcode-build-optimization-agent-skill/xcode-compilation-analyzer/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/avdlee/xcode-build-optimization-agent-skill/xcode-compilation-analyzer"><img src="https://agentmods.dev/badge/skills/avdlee/xcode-build-optimization-agent-skill/xcode-compilation-analyzer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
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 | $0.00074 | $0.01080 |
| Opus 5.5 | $0.00030 | $0.00432 |
| Sonnet 5.5 | $0.00015 | $0.00216 |
| Haiku 4.5 | $0.00007 | $0.00108 |
Grade A, and why
xcode-compilation-analyzer 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.
Copies of this mod
4 near-identical copies found in the catalogue:
- xcode-compilation-analyzer — 100% identical, 0 lines differ
- xcode-compilation-analyzer — 100% identical, 2 lines differ
- xcode-compilation-analyzer — 100% identical, 0 lines differ
- xcode-compilation-analyzer — 95% identical, 2 lines differ
How it starts
The opening of the file, as written. The whole thing — 90 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Xcode Compilation Analyzer
Use this skill when compile time, not just general project configuration, looks like the bottleneck.
Core Rules
- Start from evidence, ideally a recent
.build-benchmark/artifact or raw timing-summary output. - Prefer analysis-only compiler flags over persistent project edits during investigation.
- Rank findings by expected wall-clock impact, not cumulative compile-time impact. When compile tasks are heavily parallelized (sum of compile categories >> wall-clock median), note that fixing individual hotspots may improve parallel efficiency without reducing build wait time.
- When the evidence points to parallelized work rather than serial bottlenecks, label recommendations as "Reduces compiler workload (parallel)" rather than "Reduces build time."
- Do not edit source or build settings without explicit developer approval.
What To Inspect
Build Timing Summaryoutput from clean and incremental builds- long-running
CompileSwiftSourcesor per-file compilation tasks SwiftEmitModuletime -- can reach 60s+ after a single-line change in large modules; if it dominates incremental builds, the module is likely too large or macro-heavyPlanning Swift moduletime -- if this category is disproportionately large in incremental builds (up to 30s per module), it signals unexpected input invalidation or macro-related rebuild cascading- ad hoc runs with:
-Xfrontend -warn-long-expression-type-checking=<ms>-Xfrontend -warn-long-function-bodies=<ms>
- deeper diagnostic flags for thorough investigation:
-Xfrontend -debug-time-compilation-- per-file compile times to rank the slowest files-Xfrontend -debug-time-function-bodies-- per-function compile times (unfiltered, complements the threshold-based warning flags)-Xswiftc -driver-time-compilation-- driver-level timing to isolate driver overhead-Xfrontend -stats-output-dir <path>-- detailed compiler statistics (JSON) per compilation unit for root-cause analysis
- mixed Swift and Objective-C surfaces that increase bridging work
What ships with it
4 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.
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 · 90 lines · 74 tokens per session scan A c49d8bf206d6
xcode-compilation-analyzer is a skill published in the GitHub repository AvdLee/Xcode-Build-Optimization-Agent-Skill (1,262 stars, last pushed 1mo ago), licensed MIT. It adds 74 tokens to every session and 1,080 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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