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/ahmadulhoq/agentskel/systematic-debuggernpx skills add ahmadulhoq/agentskel --skill systematic-debuggergit clone --depth 1 https://github.com/ahmadulhoq/agentskelWrote 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/ahmadulhoq/agentskel/systematic-debugger)<a href="https://agentmods.dev/skills/ahmadulhoq/agentskel/systematic-debugger"><img src="https://agentmods.dev/badge/skills/ahmadulhoq/agentskel/systematic-debugger.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 | $0.00046 | $0.00508 |
| Opus 5 | $0.00023 | $0.00254 |
| Sonnet 5 | $0.00009 | $0.00102 |
| Haiku 4.5 | $0.00005 | $0.00051 |
Grade A, and why
systematic-debugger 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 Debugger Skill
Purpose: Stop hallucination loops. Every code change requires a verified hypothesis and a failing test first.
Prohibited Behaviors
- Adding
console.log/print/ debug statements without a stated hypothesis. - Changing code to "see what happens."
- Fixing code before a failing test exists.
- Treating the first hypothesis as confirmed without ruling out alternatives.
Techniques
| Technique | When to use |
|---|---|
| Root Cause Tracing | Follow the call stack up to the originating decision point |
| Defense in Depth | Audit every layer: input validation → business logic → persistence |
| Bisect | Binary-search commits or code paths to find the introduction point |
Required Steps (in order)
- Reproduce the bug reliably. If unable, state why and stop.
- Hypothesize: "The bug is caused by [X] because [evidence Y]."
- List alternatives: at least 2 other hypotheses to rule out.
- Create a failing test that reproduces the bug. Run it — must fail.
- Isolate root cause using a technique above. Rule out alternatives explicitly.
- Fix with minimum code targeting the confirmed root cause only.
- Verify: failing test now passes; full suite has no regressions.
- Log: update
.memory/LESSONS.mdwith root cause + prevention rule.
Common Rationalizations
| Rationalization | Why it's wrong | Do this instead |
|---|---|---|
| "I'll just try changing X and see" | That's the loop we're breaking | State a hypothesis first |
| "The test is hard to write here" | Difficulty ≠ exemption | Document why and get explicit sign-off |
| "I'm pretty sure it's Y" | Pretty sure ≠ confirmed | Rule out alternatives before fixing |
| "I'll add a log to check" | Logs without hypotheses produce noise | State what you expect the log to show first |
Gate: Do not change production code until step 4 (failing test) is complete and step 5 (root cause confirmed) is documented.
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 · 48 lines · 46 tokens per session scan A fa110b98f1f2
systematic-debugger is a skill published in the GitHub repository ahmadulhoq/agentskel (13 stars, last pushed 18d ago), licensed MIT. It adds 46 tokens to every session and 508 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 2026-09-02.
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