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/archive228/loopkit/systematic-debuggingnpx skills add Archive228/loopkit --skill systematic-debugginggit clone --depth 1 https://github.com/Archive228/loopkitWhat 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 | $0.00036 | $0.00409 |
| Opus 5 | $0.00018 | $0.00204 |
| Sonnet 5 | $0.00007 | $0.00082 |
| Haiku 4.5 | $0.00004 | $0.00041 |
Grade A, and why
systematic-debugging 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.
What it actually says
Systematic Debugging
The single most expensive agent failure: seeing an error and immediately generating a "fix" based on the error type, without reading what actually happened. Don't.
The loop
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Read the whole error. The entire message and stack trace. A TypeError can mean a hundred different things — the trace tells you which one. Quote the exact line that throws.
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Reproduce it first. If you can't reproduce it, you can't verify a fix. Write the smallest input that triggers it. "I think this fixes it" is gambling, not debugging.
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Form one hypothesis, name it. "I think the value is null because the upstream call returns 204 with no body." State it before you touch anything.
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Change one thing. Test. Repeat. If you change three things and it works, you don't know which one fixed it — and the other two may have added new bugs.
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Fix the root cause, not the symptom. A null check that hides a null is not a fix. Find why it's null. The underlying bug will resurface differently if you only patch the crash.
Stop conditions
- If 3 hypotheses fail, STOP and report: what you tried, what you saw, what you suspect. "I've tried X and Y, here's the output, I think it's Z but I'm not sure" beats 20 silent random attempts.
- Never add a workaround you don't understand.
Output
End with: the root cause (one sentence), the minimal fix, and the test that now proves it.
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 · 40 lines · 36 tokens per session scan A 74722b62f252
systematic-debugging is a skill published in the GitHub repository Archive228/loopkit (753 stars, last pushed 1mo ago), licensed MIT. It adds 36 tokens to every session and 409 once invoked, about $0.0002 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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