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 skills/howells/arc/refactornpx skills add howells/arc --skill refactorgit clone --depth 1 https://github.com/howells/arcWhat 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 | $0.00097 | $0.05057 |
| Opus 5 | $0.00048 | $0.02528 |
| Sonnet 5 | $0.00019 | $0.01011 |
| Haiku 4.5 | $0.00010 | $0.00506 |
Grade A, and why
refactor 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 — 372 lines — stays where its author put it; the contents beside it link to each section on GitHub.
<tool_restrictions>
EnterPlanMode and ExitPlanMode are banned. This skill is Arc's own structured process.
</tool_restrictions>
<arc_runtime>
Requires the full Arc bundle. Arc-owned paths (agents/, references/, disciplines/, templates/, scripts/, rules/, skills/) resolve from the plugin root — the directory containing agents/ and skills/. Everything else is the user's repository.
</arc_runtime>
<required_reading> Before starting, read these references:
references/architecture-patterns.md— import depth rules, boundary violationsreferences/maintainability-review.md— strict god-file, duplication, and structural simplification barreferences/complexity-optimization.md— safe optimization patterns and behavior-preservation checks
Also read, when present in the target project:
CONTEXT.mdor the relevant context fromCONTEXT-MAP.mddocs/adr/*.mdor area-specific ADRs- the most recent
docs/arc/audits/*-audit.md— prior classifications and dismissed findings
Load when relevant:
references/component-design.md— compound vs simple component patterns, when the candidate is a god-component and the split will produce a new component API.references/index.md— the full reference catalogue, when the refactor needs background you can't name a file for. </required_reading>
Architectural Refactoring
Discover structural friction, propose deep-module refactors, and create project-local RFCs.
- If the primary issue is reusable UI component cataloguing, missed shared UI package usage, or design-system component extraction, say so and stop: that work is out of scope for
/arc:refactorand belongs with the project's own design-system tooling. - If the primary issue is an overgrown component, script, module, or duplicated implementation logic, keep it in
/arc:refactor. - If the primary issue is broad codebase health, security, performance, or test coverage, recommend
/arc:audit. - If the user wants implementation, stop at a clear plan unless they explicitly ask to start implementing.
- Do not create external tracker issues unless the user explicitly asks.
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 · 372 lines · 97 tokens per session scan A 3fead3d8221a
refactor is a skill published in the GitHub repository howells/arc (25 stars, last pushed 18d ago), licensed MIT. It adds 97 tokens to every session and 5,057 once invoked, about $0.0005 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.
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