diagnose-and-propose

diagnose-and-propose is a skill for Claude Code from jackfranklin/dotfiles. It costs 67 tokens per session (1,110 once invoked), scanned A, original, MIT.

A debugging guide that investigates a failed build, test, command, or running program before suggesting a fix. It follows the error from its first reported location through the related source code.

In plain words
What is it for?
Use it to reproduce failures, capture the full error and stack trace, trace the root cause, and propose fixes only after the cause is confirmed.
Why use it?
It reduces guesswork and avoids treating follow-up errors as separate problems when they come from one underlying cause.

Skill for Claude Code

Written for Claude Code: disable-model-invocation in frontmatter.

Good fit Use it to reproduce failures, capture the full error and stack trace, trace the root cause, and propose fixes only after the cause is confirmed.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jackfranklin/dotfiles/diagnose-and-propose
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 jackfranklin/dotfiles --skill diagnose-and-propose
Clone the repo
git clone --depth 1 https://github.com/jackfranklin/dotfiles

Made for: Claude Code.

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-and-propose

README.md
[![agentmods](https://agentmods.dev/badge/skills/jackfranklin/dotfiles/diagnose-and-propose/github.svg)](https://agentmods.dev/skills/jackfranklin/dotfiles/diagnose-and-propose)
Your own site
<a href="https://agentmods.dev/skills/jackfranklin/dotfiles/diagnose-and-propose"><img src="https://agentmods.dev/badge/skills/jackfranklin/dotfiles/diagnose-and-propose/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-and-propose

Your own site · 80×15
<a href="https://agentmods.dev/skills/jackfranklin/dotfiles/diagnose-and-propose"><img src="https://agentmods.dev/badge/skills/jackfranklin/dotfiles/diagnose-and-propose.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 67 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,110 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. 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 $0.00067 $0.01110
Opus 5 $0.00034 $0.00555
Sonnet 5 $0.00013 $0.00222
Haiku 4.5 $0.00007 $0.00111

Measured 9d ago against content hash fe439c5f0476, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

diagnose-and-propose 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 9d 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/diagnose-and-propose/SKILL.md · 117 lines

How it starts

The opening of the file, as written. The whole thing — 117 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Diagnose and Propose

You are a careful debugger. Your job is to find the root cause of a failure before suggesting any fix. Do not guess. Do not propose solutions until you have traced the problem to a specific location and understand why it is failing.

Phase 1 — Reproduce

Run the failing command yourself to get fresh output. Do not rely solely on what the user has pasted — error messages may be truncated or out of date.

Capture the full output: error message, stack trace, file paths, line numbers, exit code. This is your evidence.

If there are multiple errors: before tracing anything, look for cascade patterns. If the errors share a common origin — the same missing export, the same changed interface, the same missing field — treat them as one failure with many surface points and trace the structural root once. Only split them into separate investigations if the evidence shows they have genuinely distinct causes.

Phase 2 — Trace

Work from the error outward. Follow the evidence:

  1. Identify the immediate failure point. What file, line, and symbol does the error point to? If there are multiple errors, find the first one — later errors are often cascades.

  2. Read the relevant source. Open the file(s) involved. Read enough context to understand what the code is trying to do and what it actually does. If the error chain enters compiled output (dist/, minified bundles, .pyc files), check for source maps or debug symbols first — they often make the source readable. Only treat the source as opaque if no source map exists.

  3. Follow the chain. If the immediate failure is caused by something upstream (a wrong type, a missing export, a changed interface, a bad dependency), follow it. Keep reading until you reach the actual origin of the problem — not just where it surfaces.

  4. Verify your hypothesis. Before concluding, confirm it: does your explanation account for the exact error message? Does it explain why it fails now (e.g. after a change, on this platform, with this input)?

Read the full file on GitHub · 117 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. 9d ago First seen · 117 lines · 67 tokens per session scan A fe439c5f0476

Subscribe to this mod's changes

diagnose-and-propose is a skill published in the GitHub repository jackfranklin/dotfiles (254 stars, last pushed yesterday), licensed MIT. It adds 67 tokens to every session and 1,110 once invoked, about $0.0003 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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