Software engineer

Stack trace debugger

Immediate result: The most likely root cause, the exact line to change and a command to confirm the fix.

Problem it solvesA stack trace points at a line, not at the cause, and searching the error message wastes an hour.

Download SKILL.md
Add this skill to
ChatGPTClaudeGeminiPerplexity

You paste

TypeError: Cannot read properties of undefined (reading 'map') at OrderList.tsx:14

You get

Root cause: orders is undefined on first render — the fetch hasn't resolved.

Fix: const orders = data?.orders ?? []

Confirm: reload with network throttled to Slow 3G; the list renders empty, then fills.

About this skill

About Stack trace debugger

Most debugging time goes on reading, not fixing. This skill reads a stack trace the way a senior engineer does: bottom-up, past the framework frames, to the first line of your own code that misbehaved. It then ranks the likely causes with the evidence for each, so you aren't chasing the first guess. The fix comes as a small diff, followed by a command or test that proves it worked. If the first suspect is wrong, you already have the next two. It refuses to guess at library internals and tells you which version detail it would need instead.

Stack trace debugger AI skill for Software engineer: you paste "TypeError: Cannot read properties of undefined (reading 'map') at OrderList.tsx:14" and get "Root cause: `orders` is undefined on first render — the fetch hasn't resolved."
Stack trace debugger — example input and the first lines it returns. Works in ChatGPT, Claude and Gemini.
Job profile
Software engineering · Software engineer
Works in
ChatGPT, Claude, Gemini, Copilot, Claude Code
Format
Agent Skills (SKILL.md)
Price
Free, no sign-up
Install instructions

Copy, paste, send

  1. Cold email writerCopy skillCopied ✓1 Copy the skillPress Copy skill.
  2. ANY AI ASSISTANTSKILLPaste here, then press Enter2 Paste it into a new chatChatGPT, Claude, Gemini or Copilot.
  3. ANY AI ASSISTANT3 Send your inputSend an error message or stack trace.
The skill — paste this into your AI assistant
# Skill: Stack trace debugger

You are running the "Stack trace debugger" skill for me. I work as: Software engineer. What I need from you: the most likely root cause, the exact line to change and a command to confirm the fix.

## When I send you an error message or stack trace, the code around the failing line and what I expected to happen
1. Read the trace bottom-up and name the frame where your code (not a library) fails.
2. List the two or three most likely root causes, most likely first, with the evidence for each.
3. Give the smallest code change that fixes the most likely cause.
4. Give one command or test that proves the fix worked.

## Reply in this format
- Root cause (one sentence)
- Evidence from the trace
- Fix (code diff)
- How to confirm
- If that wasn't it: next two suspects

## Rules
- Never guess at library internals; say which version-specific detail you'd need to check.
- Ask for the missing file only if the cause cannot be narrowed to three suspects.
- Use only the facts I give you; mark anything you had to assume with [ASSUMPTION].
- If something essential is missing, ask me one short question, then continue.
- No preamble or filler: start with the result.

Confirm you're ready in one line, then wait for me to send an error message or stack trace, the code around the failing line and what I expected to happen.

Then sendAn error message or stack trace, the code around the failing line and what you expected to happen. For example: TypeError: Cannot read properties of undefined (reading 'map') at OrderList.tsx:14

ChatGPT

  1. Fastest: paste the skill as your first message in a new chat, then send your input.
  2. To keep it: open a Project, choose Instructions (or Settings → Personalization → Custom instructions for every chat) and paste it there.
  3. To share it with a team: create a custom GPT and paste the skill into its Instructions.
  4. In the Codex app: copy the skill's folder into ~/.codex/skills/ (or Customize → Skills → Add → Create skill).

Claude

  1. Fastest: paste the skill as your first message in a new chat, then send your input.
  2. To keep it: create a Project, open Project instructions and paste the skill.
  3. As a Claude Skill: download the skill's ZIP, then in Claude open Settings → Skills → Add → Upload skill and choose the file.

Gemini

  1. Fastest: paste the skill as your first message in a new chat, then send your input.
  2. To keep it: open Gems → New Gem, paste the skill into Instructions and save.

Microsoft Copilot

  1. Fastest: paste the skill as your first message, then send your input.
  2. In Microsoft 365 Copilot, save it as a prompt or paste it into an agent's instructions to reuse it.

Any other assistant

  1. Paste the skill as the system prompt or first message in any chat assistant (Perplexity, Meta AI, DeepSeek, Mistral, local models).
  2. Coding agents that read the Agent Skills format (SKILL.md) can load the downloaded file from their skills folder.

Install it permanently

Upload it to Claude, add it to ChatGPT's Codex app, clone it into Claude Code, or download the SKILL.md for any agent. Full guide with screenshots →

Download the ZIP and upload it in Claude. Claude then uses the skill on its own whenever a request matches.

Download ZIP

Quick setup

  1. In Claude, open Settings → Skills (under Customize).
  2. Click Add → Upload skill.
  3. Choose the ZIP — don't unzip it — and make sure the skill is switched on.
Claude Settings with Skills selected under Customize, and the Add menu open showing Upload skill, Create a skill, Create with Claude and Record your screen

Repositoryscienceofapps.com/skills/ai-skills.git · all 200 skills, one folder each, plain git over HTTPS

What it does

The steps it follows

  1. Read the trace bottom-up and name the frame where your code (not a library) fails.
  2. List the two or three most likely root causes, most likely first, with the evidence for each.
  3. Give the smallest code change that fixes the most likely cause.
  4. Give one command or test that proves the fix worked.
What you get back

The reply format

  • Root cause (one sentence)
  • Evidence from the trace
  • Fix (code diff)
  • How to confirm
  • If that wasn't it: next two suspects

Rules it never breaks

  • Never guess at library internals; say which version-specific detail you'd need to check.
  • Ask for the missing file only if the cause cannot be narrowed to three suspects.
  • Uses only the facts you give it and marks assumptions.
FAQs

Questions about Stack trace debugger

What does the Stack trace debugger skill do?

A stack trace points at a line, not at the cause, and searching the error message wastes an hour. The skill fixes that: the most likely root cause, the exact line to change and a command to confirm the fix.

How do I install Stack trace debugger in ChatGPT, Claude or Gemini?

Copy the skill and paste it as the first message of a new chat, then send your input. To keep it, paste it into a ChatGPT Project or custom GPT, a Claude Project or a Gemini Gem, or upload the SKILL.md file as a Claude Skill.

What do I send Stack trace debugger after installing it?

Send an error message or stack trace, the code around the failing line and what you expected to happen. If something essential is missing, the skill asks you one short question and then continues.

Is the Stack trace debugger skill free?

Yes. It's free to copy, use and adapt, with no sign-up, and works in the free versions of ChatGPT, Claude, Gemini and Copilot.

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You paste

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You get

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