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.
git 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/commands/charleswiltgen/axiom/modernize)<a href="https://agentmods.dev/commands/charleswiltgen/axiom/modernize"><img src="https://agentmods.dev/badge/commands/charleswiltgen/axiom/modernize.svg" alt="Measured on agentmods" 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 | $0.00019 | $0.00251 |
| Opus 5 | $0.00010 | $0.00125 |
| Sonnet 5 | $0.00004 | $0.00050 |
| Haiku 4.5 | $0.00002 | $0.00025 |
Grade A, and why
modernize 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 8d 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
1 near-identical copy found in the catalogue:
- axiom-modernize — 91% identical, 10 lines differ
What it actually says
Modernize iOS Code
Launches the modernization-helper agent to find legacy patterns and give you the migration path for each.
Shorthand for /axiom:audit modernization — same agent, fewer keystrokes.
What It Does
The agent will:
- Scan for
ObservableObject/@Publishedthat should become@Observable - Find
@StateObjectand@ObservedObjectthat should become@State/@Bindable - Flag deprecated SwiftUI APIs still in use, with their replacements
- Identify UIKit patterns that have a modern SwiftUI or scene-lifecycle equivalent
- Give a migration path per finding rather than a bare list, so you can adopt incrementally
Prefer Natural Language?
You can also trigger this agent by saying:
- "How do I migrate from ObservableObject to @Observable?"
- "Are there any deprecated APIs in my SwiftUI code?"
- "Update my code to use modern SwiftUI patterns"
- "Should I still use @StateObject?"
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.
- 8d ago First seen · 29 lines · 19 tokens per session scan A 47144c5a5c86
modernize is a command published in the GitHub repository CharlesWiltgen/Axiom (1,148 stars, last pushed 2d ago), licensed MIT. It adds 19 tokens to every session and 251 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 2026-08-30.
Other commands, from other repositories
initialize-ios
Manual override: initialize ast-index for iOS/Swift/ObjC project.
kmp-implement-feature
KMP Agent Skills — build a new KMP feature end-to-end, layer by layer, with the full Koin 4 / Ktor 3 / SQLDelight 2 / CMP 1.11 stack wired correctly from the start.
create-activity
Generate a Jetpack Compose screen with proper architecture.
swift-new
Create new Swift project or component.
checklist
Generate a custom checklist for the current feature based on user requirements.
clarify
Identify underspecified areas in the current feature spec by asking up to 5 highly targeted clarification questions and encoding answers back into the spec.