Borrowing it
Nothing to install: this file belongs to asta-nguyen/kamehadb. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/asta-nguyen/kamehadb/main/.agents/skills/systematic-debugging/SKILL.mdgit clone --depth 1 https://github.com/asta-nguyen/kamehadbWrote 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/asta-nguyen/kamehadb/systematic-debugging)<a href="https://agentmods.dev/skills/asta-nguyen/kamehadb/systematic-debugging"><img src="https://agentmods.dev/badge/skills/asta-nguyen/kamehadb/systematic-debugging/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/asta-nguyen/kamehadb/systematic-debugging"><img src="https://agentmods.dev/badge/skills/asta-nguyen/kamehadb/systematic-debugging.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 | $0.00037 | $0.02086 |
| Opus 5.5 | $0.00015 | $0.00834 |
| Sonnet 5.5 | $0.00007 | $0.00417 |
| Haiku 4.5 | $0.00004 | $0.00209 |
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 19d 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.
This is a copy
100% identical to systematic-debugging — 379 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 167 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Systematic Debugging
Iron Law
NO FIXES WITHOUT ROOT CAUSE INVESTIGATION FIRST
If you have not completed Phase 1, you cannot propose fixes. Symptom fixes are failure.
When to use
Use for any technical issue: test failures, bugs, unexpected behavior, performance problems, build failures, integration issues.
Especially when: under time pressure (emergencies make guessing tempting), "just one quick fix" seems obvious, a previous fix did not work, or you do not fully understand the issue. Do not skip when the issue seems simple (simple bugs have root causes too) or you are in a hurry (rushing guarantees rework).
The four phases
When implement-task calls this skill to repair an active task, keep that task's
scope and approval. Investigate and verify the fix, then return evidence and
blockers to the caller; do not run final review, archive the parent change, or
mark its task done here. A fix needing new behavior or scope returns that
decision to the caller's approval flow. Standalone debugging runs the full route.
Complete each phase before the next.
Phase 1: Root cause investigation
Before attempting any fix:
- Read error messages carefully — read stack traces completely; note line numbers, file paths, and error codes.
- Reproduce consistently — what are the exact steps? If you cannot reproduce, gather more data; do not guess.
- Check recent changes —
git diff, recent commits, new dependencies, config and environment differences. Usereview-and-verify's### Trace changed callersto list changed symbols and trace callers and string/route/config variants. Name the traced callers so Phase 4 can verify each one. - Gather evidence in multi-component systems — add diagnostic logging at each component boundary (what enters and exits each layer) and run once to see where it breaks. Treat added logs as temporary: remove them before reporting a Bug question result or entering Phase 4, and leave none in the final diff unless the approved fix requires it.
- Trace data flow — where does the bad value originate, and what called this with it? Keep tracing up to the source and fix there, not at the symptom.
What ships with it
10 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 19d ago Changed · -54 lines be9e700952d7
- 26d ago Changed · +25 lines 3801f0785f19
- 1mo ago Changed · -95 lines · +16 tokens per session b934b423155a
- 2mo ago First seen · 291 lines · 21 tokens per session scan A ec295cbf5079
systematic-debugging is a skill published in the GitHub repository asta-nguyen/kamehadb (14 stars, last pushed 10d ago), licensed Apache-2.0. It adds 37 tokens to every session and 2,086 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to systematic-debugging, differing in 379 lines, and is treated as a copy.
systematic-debugging compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| systematic-debuggingasta-nguyen/kamehadb | Skill | 14 | 10d ago | Apache-2.0 | A | 37 | Claude Code, Codex |
| reproduce-buggoogleapis/mcp-toolbox | Skill | 17k | yesterday | Apache-2.0 | A | 130 | Claude Code, Codex |
| fix-failing-testsgoogleapis/mcp-toolbox | Skill | 17k | yesterday | Apache-2.0 | A | 87 | Claude Code, Codex |
| triage-issuesgoogleapis/mcp-toolbox | Skill | 17k | yesterday | Apache-2.0 | A | 164 | Claude Code, Codex |
| statusnicholasglazer/gnosis-mcp | Skill | 31 | 22d ago | MIT | A | 31 | Claude Code |
| slow-query-optimizeDeepSQLAI/deepsql | Skill | 40 | 5d ago | Apache-2.0 | A | 28 | Claude Code, Codex |
| remote-serveranatolykoptev/dozor | Skill | 6 | 2d ago | MIT | A | 45 | Claude Code, Codex |