diagnose

diagnose is a skill for Claude Code, Codex from Justinmendezai/The-Adam-Repo. It costs 51 tokens per session (790 once invoked), scanned A, original, Apache-2.0.

A step-by-step method for finding the cause of a difficult bug or performance slowdown. It reproduces the problem, reduces it to a small example, tests one explanation, fixes the cause, and adds a regression test.

In plain words
What is it for?
Use it when the root cause of a bug or performance regression is unclear. It helps investigate failures in tests, HTTP requests, or browser interactions.
Why use it?
It replaces guesswork with evidence and leaves behind a test that helps prevent the same problem from returning.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it when the root cause of a bug or performance regression is unclear. It helps investigate failures in tests, HTTP requests, or browser interactions.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/justinmendezai/the-adam-repo/diagnose
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 Justinmendezai/The-Adam-Repo --skill diagnose
Clone the repo
git clone --depth 1 https://github.com/Justinmendezai/The-Adam-Repo

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 diagnose

README.md
[![agentmods](https://agentmods.dev/badge/skills/justinmendezai/the-adam-repo/diagnose/github.svg)](https://agentmods.dev/skills/justinmendezai/the-adam-repo/diagnose)
Your own site
<a href="https://agentmods.dev/skills/justinmendezai/the-adam-repo/diagnose"><img src="https://agentmods.dev/badge/skills/justinmendezai/the-adam-repo/diagnose/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 diagnose

Your own site · 80×15
<a href="https://agentmods.dev/skills/justinmendezai/the-adam-repo/diagnose"><img src="https://agentmods.dev/badge/skills/justinmendezai/the-adam-repo/diagnose.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 51 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 790 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
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 $0.00051 $0.00790
Opus 5 $0.00026 $0.00395
Sonnet 5 $0.00010 $0.00158
Haiku 4.5 $0.00005 $0.00079

Measured 12d ago against content hash 6c54bc0c9e8d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

diagnose 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 12d 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.

Makes network callslowCapability

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

- A `curl` command that returns the wrong output, or
skills/diagnose/SKILL.md · 90 lines

How it starts

The opening of the file, as written. The whole thing — 90 lines — stays where its author put it; the contents beside it link to each section on GitHub.

diagnose

Adapted from Matt Pocock's diagnose. Stops the "try random fixes" anti-pattern.

The loop

1. REPRODUCE — get a reliable repro
2. MINIMIZE — strip the repro to the smallest case that still fails
3. HYPOTHESIZE — name a single concrete hypothesis
4. INSTRUMENT — add the cheapest probe that confirms or refutes it
5. CONFIRM — run; read the output; the hypothesis is true or false
6. FIX — change the smallest thing that resolves the cause
7. REGRESS — write a test that would have caught this

Each step has a clear pass/fail. If you skip ahead, you're guessing.

REPRODUCE

You don't have a bug; you have a story about a bug. Convert the story to a script:

  • A failing unit test, or
  • A curl command that returns the wrong output, or
  • A click sequence in cursor-ide-browser that yields the wrong screen.

If you can't reproduce, you can't diagnose. Time spent hunting a repro is never wasted.

MINIMIZE

Now strip everything not necessary to the failure:

  • Removing a dep — does it still fail?
  • Removing a function call — does it still fail?
  • Smaller input — does it still fail?

Stop when removing one more thing makes the bug disappear.

HYPOTHESIZE

Write down one sentence: "The bug is caused by X." Not "It might be X or Y or Z." Pick one. The next step will prove or disprove it.

INSTRUMENT

Add the cheapest probe:

  • A console.log at the suspected branch.
  • A breakpoint in the debugger.
  • A query against the DB to check actual stored state.
  • A network log via the logger MCP.

The probe should produce a one-line yes/no answer to the hypothesis. If it can't, simplify the hypothesis.

CONFIRM

Run. Read. Either:

  • The hypothesis is true → proceed to FIX.
  • The hypothesis is false → form a new hypothesis. Do not skip back to a fix; re-enter HYPOTHESIZE.

FIX

Smallest possible change. If you're tempted to "also fix" something else nearby, stop. Open a separate slice or note.

REGRESS

Read the full file on GitHub · 90 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. 12d ago First seen · 90 lines · 51 tokens per session scan A 6c54bc0c9e8d

Subscribe to this mod's changes

diagnose is a skill published in the GitHub repository Justinmendezai/The-Adam-Repo (12 stars, last pushed 18d ago), licensed Apache-2.0. It adds 51 tokens to every session and 790 once invoked, about $0.0003 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 2026-08-31.

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