debugging

A step-by-step method for finding the underlying cause of bugs, failed tests, build problems, and other unexpected behavior before changing code.

In plain words
What is it for?
Use it to investigate production bugs, test failures, performance issues, build failures, and integration problems.
Why use it?
It prevents quick patches that hide the real problem or create new bugs.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/hitmandark07/neatcodeai/debugging
Any agent
npx skills add HITMANdark07/neatcodeai --skill debugging
Clone the repo
git clone --depth 1 https://github.com/HITMANdark07/neatcodeai

Made for: Claude Code, Codex.

Per session 19 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,051 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00019 $0.02051
Opus 5 $0.00010 $0.01026
Sonnet 5 $0.00004 $0.00410
Haiku 4.5 $0.00002 $0.00205

Measured yesterday against content hash 990393b37fb4, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

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 yesterday.

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.

packages/cli/templates/skills/debugging/SKILL.md · 213 lines

How it starts

The opening of the file, as written. The whole thing — 213 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Systematic Debugging

Overview

Random fixes waste time and create new bugs. Quick patches mask underlying issues.

Core principle: ALWAYS find root cause before attempting fixes. Symptom fixes are failure.

Violating the letter of this process is violating the spirit of debugging.

This skill calls the query_graph, trace_flow, and find_node MCP tools during Phase 1. The graph is faster and more accurate than text search for tracing where bad data originates and which components touch a value.

The Iron Law

NO FIXES WITHOUT ROOT CAUSE INVESTIGATION FIRST

If you haven't completed Phase 1, you cannot propose fixes.

When to Use

Use for ANY technical issue:

  • Test failures
  • Bugs in production
  • Unexpected behavior
  • Performance problems
  • Build failures
  • Integration issues

Use this ESPECIALLY when:

  • Under time pressure (emergencies make guessing tempting)
  • "Just one quick fix" seems obvious
  • You've already tried multiple fixes
  • Previous fix didn't work
  • You don't fully understand the issue

Don't skip when:

  • Issue seems simple (simple bugs have root causes too)
  • You're in a hurry (rushing guarantees rework)
  • Manager wants it fixed NOW (systematic is faster than thrashing)

The Four Phases

You MUST complete each phase before proceeding to the next.

Phase 1: Root Cause Investigation

BEFORE attempting ANY fix:

  1. Route the question through the graph FIRST

    Before grepping or reading source files, query the graph. The graph already knows callers, callees, parent-child, who-extends-this, and where annotations are applied. Text search re-derives this every time and gets it wrong on indirection.

    Tool selection:

    • query_graph — find all callers of a symbol, all who-extend-this, who-imports-this. Use this first when the symptom mentions a function, class, or module name.
    • trace_flow — multi-hop call chain with annotations on each step. Use when the symptom is "what runs when X happens" (a request, an event, a hook firing).
    • find_node — resolve an exact qualified_name when you already have a fully-qualified handle. Use when you need to confirm a single symbol exists or grab its file:line.

Read the full file on GitHub · 213 lines

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. yesterday First seen · 213 lines · 19 tokens per session scan A 990393b37fb4

Subscribe to this mod's changes

debugging is a skill published in the GitHub repository HITMANdark07/neatcodeai (0 stars, last pushed 3mo ago), licensed MIT. It adds 19 tokens to every session and 2,051 once invoked, about $0.0001 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 2026-08-31.

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