debug

A debugging guide for finding why code fails, behaves unexpectedly, or produces an error.

In plain words
What is it for?
Use it to investigate failing tests and runtime issues, reproduce bugs, check likely causes, and document the root cause and a possible fix.
Why use it?
It turns a vague problem into a tested explanation by examining error messages, recent changes, and the code path involved.

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/seifbenayed/cloclo/debug
Any agent
npx skills add SeifBenayed/cloclo --skill debug
Clone the repo
git clone --depth 1 https://github.com/SeifBenayed/cloclo

Made for: Claude Code, Codex.

Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 369 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 $0.00033 $0.00369
Opus 5 $0.00016 $0.00185
Sonnet 5 $0.00007 $0.00074
Haiku 4.5 $0.00003 $0.00037

Measured 2d ago against content hash 5511f0721fba, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

debug 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 2d 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.

.claude/skills/debug/SKILL.md · 46 lines

What it actually says

Debug

Help diagnose and troubleshoot the described issue or the most recent error.

Steps

  1. Understand the problem

    • Read any error messages or stack traces mentioned
    • Ask clarifying questions if the problem description is vague
    • Check recent git changes that might have caused the issue: git diff HEAD~3
  2. Reproduce

    • If there's a failing test, run it to see the exact error
    • If it's a runtime issue, try to reproduce with minimal steps
  3. Investigate

    • Find the relevant source files using the stack trace or error message
    • Trace the code path that leads to the error
    • Check for common issues:
      • Typos in variable or function names
      • Wrong types or missing type conversions
      • Missing imports or dependencies
      • Race conditions or async issues
      • Environment differences (missing env vars, wrong paths)
      • Recent changes that broke assumptions
  4. Form a hypothesis and verify

    • State what you think the root cause is
    • Find evidence in the code that supports or refutes it
    • If needed, add targeted logging to narrow down the issue
  5. Report findings

    • Root cause explanation (why it broke, not just what broke)
    • Suggested fix with specific code changes
    • How to prevent similar issues in the future

Do NOT make changes unless explicitly asked — diagnose and explain first. The user should decide whether and how to fix it.

$ARGUMENTS

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. 2d ago First seen · 46 lines · 33 tokens per session scan A 5511f0721fba

Subscribe to this mod's changes

debug is a skill published in the GitHub repository SeifBenayed/cloclo (114 stars, last pushed 4mo ago), licensed MIT. It adds 33 tokens to every session and 369 once invoked, about $0.0002 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 2026-08-30.

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