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 commands/bitsmuggler/c4-skill/c4git clone --depth 1 https://github.com/bitsmuggler/c4-skillWhat 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 | $0.00012 | $0.00817 |
| Opus 5 | $0.00006 | $0.00409 |
| Sonnet 5 | $0.00002 | $0.00163 |
| Haiku 4.5 | $0.00001 | $0.00082 |
Grade A, and why
c4 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.
The source is not reproduced here
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
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 · 68 lines · 12 tokens per session scan A 6d4e417fabda
c4 is a command published in the GitHub repository bitsmuggler/c4-skill (56 stars, last pushed 6mo ago), with no licence file. It adds 12 tokens to every session and 817 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
arch4-seed
Create this repository's initial Arch4 architecture model.
arch4-create-support-request
Help the user create a GitHub issue for Arch4 only. This workflow is for Arch4 product bugs, installation problems, documentation issues, and feature requests. If the request is about the user's own project rather than Arch4, explain that Arch4 can only file Arch4 product issues and stop.
arch4-update
Update this repository's Arch4 architecture model.
arch4-review
Review whether the current repository changes require Arch4 updates.
arch4-open-map
Show this repository's rendered Arch4 architecture map widget.
arch4-build-artifacts
Build this repository's Arch4 rendered artifacts and show the map.