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.
npx skills add neurofoo/agent-skills --skill 5whysgit clone --depth 1 https://github.com/neurofoo/agent-skillsWrote 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.
[](https://agentmods.dev/skills/neurofoo/agent-skills/5whys)<a href="https://agentmods.dev/skills/neurofoo/agent-skills/5whys"><img src="https://agentmods.dev/badge/skills/neurofoo/agent-skills/5whys.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00039 | $0.00821 |
| Opus 5 | $0.00019 | $0.00411 |
| Sonnet 5 | $0.00008 | $0.00164 |
| Haiku 4.5 | $0.00004 | $0.00082 |
Grade A, and why
5whys 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 8d 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.
How it starts
The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Five Whys Analysis
Perform iterative root cause analysis by asking "why" repeatedly until you reach the underlying cause.
Instructions
Start with the stated problem and ask "why" it occurred. For each answer, ask "why" again. Continue until you reach a root cause that:
- Is actionable (you can do something about it)
- Is fundamental (asking "why" further leads to abstract/unhelpful answers)
- Explains the chain of causation
Typically this takes 5 iterations, but may be fewer or more.
Output Format
Problem Statement Restate the problem clearly and specifically.
Why Chain
| Level | Question | Answer |
|---|---|---|
| 1 | Why did [problem]? | [Answer 1] |
| 2 | Why did [Answer 1]? | [Answer 2] |
| 3 | Why did [Answer 2]? | [Answer 3] |
| 4 | Why did [Answer 3]? | [Answer 4] |
| 5 | Why did [Answer 4]? | [Root Cause] |
Root Cause The fundamental issue identified. Explain why this is the root (not just another symptom).
Branches (if applicable) If multiple valid answers exist at any level, show the branching analysis.
Corrective Actions
- Immediate: What to do now to address the symptom
- Systemic: What to change to prevent recurrence
Verification How will you confirm the root cause is correct? (Test the hypothesis)
Guidelines
- Each answer should be factual and verifiable
- Avoid blame ("John didn't do X")—focus on systems and processes
- If you're guessing, note it as a hypothesis to verify
- Watch for circular logic
- It's okay to branch if there are multiple valid causes
- Stop when further "why" questions become philosophical or unhelpful
Examples
Software Bug
Problem: Users are seeing 500 errors on the checkout page
| Level | Question | Answer |
|---|---|---|
| 1 | Why are users seeing 500 errors? | The payment service is timing out |
| 2 | Why is the payment service timing out? | Database queries are taking >30 seconds |
| 3 | Why are database queries slow? | The orders table has 50M rows and no index on customer_id |
| 4 | Why is there no index? | The table was created before we had this query pattern |
| 5 | Why wasn't an index added when the query was added? | No database review process for new queries |
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.
- 8d ago First seen · 96 lines · 39 tokens per session scan A 8f2555d13c75
5whys is a skill published in the GitHub repository neurofoo/agent-skills (111 stars, last pushed 7mo ago), licensed MIT. It adds 39 tokens to every session and 821 once invoked, about $0.0002 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.
Other skills, from other repositories
debug-optimize-lcp
Guides debugging and optimizing Largest Contentful Paint (LCP) using Chrome DevTools MCP tools. Use this skill whenever the user asks about LCP performance, slow page loads, Core Web Vitals optimization, or wants to understand why their page's main content takes too long to appear. Also use when the user mentions…
systematic-debugging
Use when debugging a failing test, build error, or runtime issue that isn't immediately obvious. Guides a 4-phase root cause analysis instead of random fix attempts.
diagnose
Trace from a reproduced symptom to the source code that causes it. Pin the specific file and approximate line, rate confidence in the cause and clarity of the fix independently, and always propose a concrete fix.
repro-admin
Reproduce an EmDash admin UI bug. Attach a container, start the demo dev server, drive the admin with agent-browser using the dev-bypass session, and capture the reproduction as screenshots plus a replayable transcript.
log-error-digest
Analyze log files to troubleshoot errors, identify peak error periods, and produce error clustering, frequency statistics, and time distribution reports. Supports JSON, syslog, and Nginx formats with automatic detection. Use when a user uploads a .log file and asks to analyze errors, find patterns, debug issues, or…
byted-util-volcengine-detect-retry
An orchestration workflow for Volcengine Cloud Detect, a service that checks websites or network endpoints from test locations.