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 existential-birds/beagle --skill swift-code-reviewgit clone --depth 1 https://github.com/existential-birds/beagleWrote 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/existential-birds/beagle/swift-code-review)<a href="https://agentmods.dev/skills/existential-birds/beagle/swift-code-review"><img src="https://agentmods.dev/badge/skills/existential-birds/beagle/swift-code-review/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/existential-birds/beagle/swift-code-review"><img src="https://agentmods.dev/badge/skills/existential-birds/beagle/swift-code-review.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 | $0.00047 | $0.00992 |
| Opus 5.5 | $0.00019 | $0.00397 |
| Sonnet 5.5 | $0.00009 | $0.00198 |
| Haiku 4.5 | $0.00005 | $0.00099 |
Grade A, and why
swift-code-review 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 — 80 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Swift Code Review
Review Workflow
Follow this sequence in order. Do not emit findings until every Pass below is satisfied.
-
Swift / toolchain baseline — Establish language and tooling context:
Package.swift// swift-tools-versionand any per-target Swift language version orswiftSettingsin the manifest; for Xcode,SWIFT_VERSION(or equivalent) in project or target build settings; note if review is single-file only.
Pass: You state a concrete Swift language version or mode (e.g. Swift 6 language mode, tools 5.10) before advice that depends on strict concurrency, migration-only syntax, or SDK availability. -
Read surrounding code — For each changed
.swiftfile, read the full enclosing type, function, method, or property that contains the edits, not only the diff hunk.
Pass: At least one full enclosing symbol (type or member) containing the change was read per changed file. -
Scope the checklist — Using Quick Reference, decide which Review Checklist rows and references apply; open those reference files; skip rows clearly unrelated to the diff.
Pass: The review (or working notes) lists which checklist areas you applied, or marks areas N/A with a one-line reason tied to the diff (e.g. “no SwiftUI / @Observable in change”). -
Pre-report verification — Load and follow review-verification-protocol.
Pass: That skill’s Hard gates (sequenced) are satisfied for each finding you will report (full symbol read, usage search before “unused”, caller checked before “missing handling”, severity calibrated,[FILE:LINE]proof).
Hard gates (same sequence, shorter)
| Step | Objective pass condition |
|---|---|
| 1 | Swift version/mode (or explicit single-file limitation) recorded before version- or SDK-gated advice. |
| 2 | Full enclosing symbol read per changed file, not diff-only. |
| 3 | Checklist areas + references listed or N/A with diff-tied reason. |
| 4 | review-verification-protocol completed for every reported issue. |
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 · 80 lines · 47 tokens per session scan A 1fc17871c146
swift-code-review is a skill published in the GitHub repository existential-birds/beagle (82 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 47 tokens to every session and 992 once invoked, about $0.0002 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 2026-09-16.
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