Systematic debugging

Systematic debugging is a skill for Claude Code, Codex from Kilbex/Vigla. It costs 26 tokens per session (147 once invoked), scanned A, original, Apache-2.0.

A step-by-step method for finding the real cause of bugs, failed tests, or unexpected program behavior. It uses a small reproduction, one tested explanation at a time, and evidence from the code and error messages.

In plain words
What is it for?
Use it when a test fails, a feature behaves unexpectedly, or you need to investigate a bug before changing code.
Why use it?
It helps prevent guesses and temporary fixes that leave the underlying problem in place. It also checks that the fix works and has not caused other failures.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it when a test fails, a feature behaves unexpectedly, or you need to investigate a bug before changing code.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/kilbex/vigla/systematic-debugging
Install

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.

Any agent
npx skills add Kilbex/Vigla --skill systematic-debugging
Clone the repo
git clone --depth 1 https://github.com/Kilbex/Vigla

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for Systematic debugging

README.md
[![agentmods](https://agentmods.dev/badge/skills/kilbex/vigla/systematic-debugging/github.svg)](https://agentmods.dev/skills/kilbex/vigla/systematic-debugging)
Your own site
<a href="https://agentmods.dev/skills/kilbex/vigla/systematic-debugging"><img src="https://agentmods.dev/badge/skills/kilbex/vigla/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.

agentmods 80×15 button for Systematic debugging

Your own site · 80×15
<a href="https://agentmods.dev/skills/kilbex/vigla/systematic-debugging"><img src="https://agentmods.dev/badge/skills/kilbex/vigla/systematic-debugging.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 26 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 147 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00026 $0.00147
Opus 5.5 $0.00010 $0.00059
Sonnet 5.5 $0.00005 $0.00029
Haiku 4.5 $0.00003 $0.00015

Measured 1mo ago against content hash f4a461e04872, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

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 1mo 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.

crates/orchestrator/resources/skills/systematic-debugging/SKILL.md · 15 lines

What it actually says

When something is broken:

  1. Reproduce it with the smallest possible input, ideally a failing test.
  2. Read the actual error and the surrounding code before forming a theory.
  3. Form ONE hypothesis, find the cheapest observation that would confirm or kill it, and check.
  4. Fix the root cause, not the symptom. If you cannot explain why it broke, you are not done.
  5. Re-run the reproduction to confirm the fix, then run the wider suite for regressions.
Changes

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.

  1. 1mo ago First seen · 15 lines · 26 tokens per session scan A f4a461e04872

Subscribe to this mod's changes

Systematic debugging is a skill published in the GitHub repository Kilbex/Vigla (116 stars, last pushed 18d ago), licensed Apache-2.0. It adds 26 tokens to every session and 147 once invoked, about $0.0001 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 2026-08-30.

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