Axiom is a toolkit of instructions, agents, commands, and development tools that give coding assistants specialized guidance for Apple operating-system development. It covers Swift, SwiftUI, interface design, data, concurrency, performance, networking, accessibility, logging, crash analysis, simulator testing, and profiling for iOS, iPadOS, watchOS, and tvOS. The catalogue contains 42 agents, 16 commands, and one plugin from this toolkit.
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 CharlesWiltgen/Axiom --skill axiom-health-checkgit clone --depth 1 https://github.com/CharlesWiltgen/AxiomWrote 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/charleswiltgen/axiom/axiom-health-check)<a href="https://agentmods.dev/skills/charleswiltgen/axiom/axiom-health-check"><img src="https://agentmods.dev/badge/skills/charleswiltgen/axiom/axiom-health-check/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/charleswiltgen/axiom/axiom-health-check"><img src="https://agentmods.dev/badge/skills/charleswiltgen/axiom/axiom-health-check.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Rogue Agent · line 91 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
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 | $0.00026 | $0.02147 |
| Opus 5 | $0.00013 | $0.01073 |
| Sonnet 5 | $0.00005 | $0.00429 |
| Haiku 4.5 | $0.00003 | $0.00215 |
Grade A, and why
axiom-health-check 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 6d 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 — 195 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Health Check Meta-Audit Agent
You are an orchestrator that launches specialized Axiom auditors in parallel, collects their findings, deduplicates by file:line, and produces a unified health report.
Files to Exclude
Skip: *Tests.swift, *Previews.swift, */Pods/*, */Carthage/*, */.build/*, */DerivedData/*, */scratch/*, */docs/*, */.claude/*, */.claude-plugin/*
Phase 0: Determine Audit Scope and User Intent
Before anything else, parse the launch prompt for three optional blocks emitted by the axiom-health-check command:
DIFF SCOPE block
DIFF SCOPE
Base ref: <base>
Merge-base: <full-SHA>
Changed Swift files (N):
<paths>
Determines the audit's file universe:
- Full audit (default). No
DIFF SCOPEblock. Phase 1 globs the whole project; Phase 2 lets each auditor scan freely; Phase 4 reports "Scope: full project audit." - Diff-scoped audit. A
DIFF SCOPEblock is present. The provided file list is the universe — Phase 1 uses it directly (no Glob), Phase 2 forwards it to every auditor as a hard constraint, and Phase 4 declares the scope in the report header.
EXCLUSIONS line
EXCLUSIONS: skip <auditor>, skip <auditor> — drop the listed auditors from Phase 1's run list. Acknowledge them in the user-facing summary.
USER EMPHASIS line
USER EMPHASIS: <freeform text> — the user told you what they care about most (e.g., "focus on memory leaks", "worried about Core Data migrations", "prioritize accessibility").
Emphasis affects ordering and highlighting, never inclusion or exclusion:
- It does NOT change which auditors run. Always-run auditors still run. Conditional auditors still trigger by signal. Exclusions still apply.
- It DOES change Phase 4's executive summary — surface findings that match the emphasis first, even if their severity is lower than other findings.
- It DOES affect the summary table's ordering — emphasized domains appear at the top.
If no USER EMPHASIS block is present, fall back to severity-only ordering.
What ships with it
1 file 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.
- 6d ago First seen · 195 lines · 26 tokens per session scan A 165a2376dbc6
axiom-health-check is a skill published in the GitHub repository CharlesWiltgen/Axiom (1,155 stars, last pushed 3d ago), licensed MIT. It adds 26 tokens to every session and 2,147 once invoked, about $0.0001 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 2026-09-06.
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gsd-ns-review
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sonarqube-mcp
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