Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add musingfox/cc-plugins/plugin install diagnoseWrote 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/musingfox/cc-plugins/diagnose)<a href="https://agentmods.dev/skills/musingfox/cc-plugins/diagnose"><img src="https://agentmods.dev/badge/skills/musingfox/cc-plugins/diagnose/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/musingfox/cc-plugins/diagnose"><img src="https://agentmods.dev/badge/skills/musingfox/cc-plugins/diagnose.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 | $0.00051 | $0.00212 |
| Opus 5.5 | $0.00020 | $0.00085 |
| Sonnet 5.5 | $0.00010 | $0.00042 |
| Haiku 4.5 | $0.00005 | $0.00021 |
Grade A, and why
diagnose 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 10d 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.
What it actually says
Diagnose
Offer the diagnosis loop, then wait. Use AskUserQuestion before any worktree exists.
If there is no observed symptom, ask for it first. Do not open a worktree against a guess.
AskUserQuestion — "Run the full diagnosis loop? It works in its own worktree and hands back a branch with a failing test; it does not apply the fix."
- Diagnose — proceed. Read
${CLAUDE_PLUGIN_ROOT}/docs/method.mdand follow it. The HITL template path the method asks for is${CLAUDE_PLUGIN_ROOT}/scripts/hitl-loop.template.sh. - Just look — answer from reading only. No worktree, no branch. Say plainly that no branch was produced.
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.
- 10d ago Changed · +30 tokens per session 14c2e5ad4ca0
- 1mo ago First seen · 17 lines · 21 tokens per session scan A b87450047eb9
diagnose is a skill published in the GitHub repository musingfox/cc-plugins (2 stars, last pushed yesterday), licensed MIT. It adds 51 tokens to every session and 212 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 2026-09-11.
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