diagnosing-bugs

A repeatable process for investigating difficult software bugs and performance regressions, where a previously acceptable program becomes slower. It is intended for debugging failures and slow behavior.

In plain words
What is it for?
Use it when code is broken, throws errors, fails tests, or becomes slow and needs diagnosis.
Why use it?
It provides a structured way to narrow down causes when a quick inspection is not enough. This helps distinguish the source of a bug or slowdown from its visible symptoms.

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/desko27/react-call/diagnosing-bugs
Any agent
npx skills add desko27/react-call --skill diagnosing-bugs
Clone the repo
git clone --depth 1 https://github.com/desko27/react-call

Made for: Claude Code, Codex.

Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,985 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
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 $0.00040 $0.01985
Opus 5 $0.00020 $0.00992
Sonnet 5 $0.00008 $0.00397
Haiku 4.5 $0.00004 $0.00198

Measured 2d ago against content hash 7a0779480f32, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 2d 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** (paste the invocation and its output),
.claude/skills/diagnosing-bugs/SKILL.md · 135 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

1 file 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. 2d ago First seen · 135 lines · 40 tokens per session scan A 7a0779480f32

Subscribe to this mod's changes

diagnosing-bugs is a skill published in the GitHub repository desko27/react-call (1,368 stars, last pushed today), with no licence file. It adds 40 tokens to every session and 1,985 once invoked, about $0.0002 per session on Opus 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 2026-08-30.

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