diagnosing-bugs

diagnosing-bugs is a skill for Claude Code, Codex from fabiandistler/agents. It costs 40 tokens per session (2,034 once invoked), scanned A, original, no licence file.

A step-by-step workflow for finding the cause of difficult bugs and slowdowns. A performance regression is a change that makes software slower or less efficient than before.

In plain words
What is it for?
Use it to diagnose bugs, failures, errors, or performance regressions.
Why use it?
It provides a structured way to investigate software that is broken, failing, throwing errors, or becoming slow.

Skill for Claude CodeCodex

Written for Claude Code and Codex: installed under .claude/, but also agents/openai.yaml present.

Good fit Use it to diagnose bugs, failures, errors, or performance regressions.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/fabiandistler/agents/diagnosing-bugs
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 fabiandistler/agents --skill diagnosing-bugs
Clone the repo
git clone --depth 1 https://github.com/fabiandistler/agents

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 diagnosing-bugs

README.md
[![agentmods](https://agentmods.dev/badge/skills/fabiandistler/agents/diagnosing-bugs/github.svg)](https://agentmods.dev/skills/fabiandistler/agents/diagnosing-bugs)
Your own site
<a href="https://agentmods.dev/skills/fabiandistler/agents/diagnosing-bugs"><img src="https://agentmods.dev/badge/skills/fabiandistler/agents/diagnosing-bugs/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 diagnosing-bugs

Your own site · 80×15
<a href="https://agentmods.dev/skills/fabiandistler/agents/diagnosing-bugs"><img src="https://agentmods.dev/badge/skills/fabiandistler/agents/diagnosing-bugs.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,034 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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 $0.00040 $0.02034
Opus 5.5 $0.00016 $0.00814
Sonnet 5.5 $0.00008 $0.00407
Haiku 4.5 $0.00004 $0.00203

Measured 15d ago against content hash 849198df88cd, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

diagnosing-bugs scanned grade A with 1 finding 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 15d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/hitl-loop.template.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

Phase 1 is done when the loop is **tight** and **red-capable**: you can name **one command** (a script path, a test invocation, a curl) that you have **already run at least once** (show the invocation and its output, red
.claude/skills/diagnosing-bugs/SKILL.md · 139 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 15d ago Changed 849198df88cd
  2. 28d ago First seen · 139 lines · 40 tokens per session scan A 9168404abda0

Subscribe to this mod's changes

diagnosing-bugs is a skill published in the GitHub repository fabiandistler/agents (2 stars, last pushed yesterday), with no licence file. It adds 40 tokens to every session and 2,034 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-10-02.

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