issue-debugging

issue-debugging is a skill for Claude Code from QBall-Inc/the-bulwark. It costs 39 tokens per session (2,624 once invoked), scanned A, original, MIT.

A structured method for investigating software bugs, finding their underlying cause, assessing what they affect, and checking that fixes really work.

In plain words
What is it for?
Use it to investigate bugs, failed tests, error messages, regressions, and requests to verify a fix.
Why use it?
It reduces the risk of fixing only the first visible error and missing related problems or broken user behavior.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: mentions subagents.

Part of the the-bulwark plugin — 30 skills, 17 agents, 6 hooks shipped together

Good fit Use it to investigate bugs, failed tests, error messages, regressions, and requests to verify a fix.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/qball-inc/the-bulwark/issue-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 QBall-Inc/the-bulwark --skill issue-debugging
Clone the repo
git clone --depth 1 https://github.com/QBall-Inc/the-bulwark

Made for: Claude Code.

Or install the-bulwark, the plugin that ships this one along with the rest of its 30 skills, 17 agents, 6 hooks.

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 issue-debugging

README.md
[![agentmods](https://agentmods.dev/badge/skills/qball-inc/the-bulwark/issue-debugging/github.svg)](https://agentmods.dev/skills/qball-inc/the-bulwark/issue-debugging)
Your own site
<a href="https://agentmods.dev/skills/qball-inc/the-bulwark/issue-debugging"><img src="https://agentmods.dev/badge/skills/qball-inc/the-bulwark/issue-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 issue-debugging

Your own site · 80×15
<a href="https://agentmods.dev/skills/qball-inc/the-bulwark/issue-debugging"><img src="https://agentmods.dev/badge/skills/qball-inc/the-bulwark/issue-debugging.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 39 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,624 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 warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Excessive Agency · line 313
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
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 $0.00039 $0.02624
Opus 5.5 $0.00016 $0.01050
Sonnet 5.5 $0.00008 $0.00525
Haiku 4.5 $0.00004 $0.00262

Measured 1mo ago against content hash f0250d5ffeea, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

issue-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.

skills/issue-debugging/SKILL.md · 391 lines

How it starts

The opening of the file, as written. The whole thing — 391 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Issue Debugging

Systematic methodology for debugging that prevents the "first error fix and declare done" anti-pattern. Ensures root cause analysis, impact assessment, and verified fixes.


When to Use This Skill

Load this skill when the user request matches ANY of these patterns:

Trigger Pattern Example User Request
Bug investigation "Why is X failing?", "Debug this error", "Investigate this issue"
Test failures "Tests are failing", "Fix the broken tests", "Why did CI fail?"
Error analysis "Getting this error...", "Exception in...", "Stack trace shows..."
Regression hunting "This used to work", "Something broke after...", "Regression in..."
Fix validation "Did the fix work?", "Verify this change", "Make sure it's fixed"
Root cause requests "What's causing this?", "Find the root cause", "Why does this happen?"

DO NOT use for:

  • New feature implementation (no existing bug)
  • Refactoring without reported issues
  • General code questions

Overview

The Problem

AI (and developers) often fix the first visible error and declare victory without verifying end-user functionality works. This leads to:

  • Symptom fixes instead of root cause fixes
  • Regressions in seemingly unrelated areas
  • False confidence in fix completeness

The Solution

This skill provides:

  1. Root Cause Analysis - Find the actual cause, not just symptoms
  2. Impact Analysis - Map affected areas and dependencies
  3. Validation Planning - Tiered test priorities (P1/P2/P3)
  4. Confidence Assessment - Objective fix reliability rating
  5. Escalation Triggers - When manual testing is required

Root Cause Analysis

The 5 Whys Method

Iteratively ask "Why?" to drill past symptoms to root cause:

Problem: Login fails with 500 error
├─ Why? → API returns null for user profile
├─ Why? → Database query found no records
├─ Why? → Migration didn't run on deploy
├─ Why? → Deployment script skipped migration step
└─ Why? → Environment variable missing

Root Cause: Missing environment variable (not the 500 error)

Read the full file on GitHub · 391 lines

Files

What ships with it

2 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.

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 · 391 lines · 39 tokens per session scan A f0250d5ffeea

Subscribe to this mod's changes

issue-debugging is a skill published in the GitHub repository QBall-Inc/the-bulwark (8 stars, last pushed today), licensed MIT. It adds 39 tokens to every session and 2,624 once invoked, about $0.0002 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 2026-08-31.

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