Systematic debugging
Skill swd3k/skills/agent-skills/programming/systematic-debugging
Portable agent skills for desktop apps, programming, UI, and web design - Codex, Claude, Cursor, Grok. English SKILL.md playbooks (Photino, Inno, CI, landings).
npx -y skills add swd3k/skills --skill systematic-debuggingAssembled from the repository path, not quoted from the project. Check it against their README if it does not work.
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- 21 days oldThe repository was created 21 days ago. New is not bad, but a brand new repository carrying a familiar-sounding name is the shape a typosquat arrives in, and there has been no time for anyone else to find a problem with it.
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What its author says it does
Copied from the file, not written here
Debug software issues with a structured reproduce → isolate → fix → regress loop. Use when facing white screens, flaky CI, production-only bugs, or vague 'it doesn't work' reports.
SKILL.md
1.4 KB, 304 tokens by cl100k_base, as published. Nobody here has run it
Systematic Debugging
Loop
- Reproduce — exact steps, OS, version, artifact (not only source).
- Define expected vs actual in one sentence each.
- Bisect — last known good commit/tag/build.
- Isolate layer — UI / host bridge / service / OS / network / packaging.
- Hypothesize one cause — test cheapest disproof first.
- Fix minimal — no drive-by refactors in the same commit.
- Regress — add a test or checklist item so it can't return silently.
Evidence > intuition
- Logs with timestamps
- Exit codes
- Network traces
- Screenshots / screen recordings
git bisectwhen regression window is large
Desktop-specific
| Symptom | First checks |
|---|---|
| White screen | asset load path, CSS blocked, JS throw |
| Works in VS, fails installed | cwd, relative paths, missing runtime |
| CI only | path case, secrets, runner OS, corrupted downloads |
| Admin only | manifest, UAC cancel path |
Output when reporting
- Root cause (one paragraph)
- Fix (what changed)
- How verified
- Residual risk
Pitfalls
- Changing 5 things at once
- "Fixed" without reproduction of original failure
- Ignoring the packaging step (only testing
dotnet run)
What ships with it
Read from the repository
Just SKILL.md. No reference files, no scripts.
Gives 1 of the 12 instructions most debug triage skills give in 304 tokens
Counted across 839 of the 1,149 authors here whose files we hold, read 2026-08-07
- Investigate root cause before proposing any fixin 102 of 839, across 67 files
- Read error messages completelyin 89 of 839, across 49 files
- Create a failing test case before fixingin 84 of 839, across 46 files
- Reproduce the issue consistentlyhere, and in 82 of 839, across 41 files
- Change one variable at a timein 82 of 839, across 42 files
- Check recent changesin 74 of 839, across 36 files
- Write the regression test before fixingin 74 of 839, across 40 files
- Fix the root cause not the symptomin 60 of 839, across 45 files
- Implement a single fix at a timein 59 of 839, across 20 files
- Trace data flow backward to the sourcein 50 of 839, across 20 files
- Remove all debug instrumentationin 49 of 839, across 13 files
- Form a single hypothesisin 48 of 839, across 18 files
Said here and by no other author read
- Bisect to find the last good version
- Commit minimal fixes only
- Gather timestamped logs
- Check exit codes
- Collect network traces
- Provide a one paragraph root cause
Grouped from the skills themselves: near-identical wordings counted once, and counted by distinct author, so one author publishing three of these counts once. Length counted with cl100k_base; the agent that loads this file may tokenize it differently.