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 umputun/cc-thingz --skill root-cause-investigatorgit clone --depth 1 https://github.com/umputun/cc-thingzWrote 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/umputun/cc-thingz/root-cause-investigator)<a href="https://agentmods.dev/skills/umputun/cc-thingz/root-cause-investigator"><img src="https://agentmods.dev/badge/skills/umputun/cc-thingz/root-cause-investigator/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.
<a href="https://agentmods.dev/skills/umputun/cc-thingz/root-cause-investigator"><img src="https://agentmods.dev/badge/skills/umputun/cc-thingz/root-cause-investigator.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00053 | $0.00745 |
| Opus 5 | $0.00026 | $0.00373 |
| Sonnet 5 | $0.00011 | $0.00149 |
| Haiku 4.5 | $0.00005 | $0.00075 |
Grade A, and why
root-cause-investigator 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 11d 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 — 118 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Root Cause Investigator
Apply systematic 5-Why methodology to identify fundamental root causes of issues rather than treating symptoms. Guide thorough investigation through structured evidence gathering and analysis.
Activation Triggers
- errors, bugs, or unexpected behavior
- build failures or test failures
- performance issues or degradation
- integration problems
- any "it's not working" scenarios
The 5-Why Methodology
Systematically ask "why" five times to drill down to root cause:
- Why #1: identify immediate cause (symptoms)
- Why #2: uncover process/workflow issues
- Why #3: find system-level problems
- Why #4: discover design/architecture issues
- Why #5: reveal fundamental root cause
Investigation Workflow
1. Gather Initial Context
Collect information about the issue:
## Issue Summary
[brief description of reported problem]
## Initial Symptoms
- what user is experiencing
- error messages or logs
- observable behavior
## Context Gathering
- environment details
- recent changes
- related components
- steps to reproduce
2. Apply 5-Why Analysis
Structure the investigation with progressive depth:
## 5-Why Analysis
### Why #1: [surface cause]
Evidence: [logs, errors, behavior]
Impact: [what this affects]
### Why #2: [deeper cause]
Evidence: [code, configuration]
Impact: [cascading effects]
### Why #3: [system cause]
Evidence: [architecture, dependencies]
Impact: [broader implications]
### Why #4: [process/design cause]
Evidence: [patterns, decisions]
Impact: [long-term effects]
### Why #5: [root cause]
Evidence: [fundamental issue]
Impact: [core problem]
3. Identify Root Cause
Document the fundamental issue requiring attention:
## Root Cause Identified
[the fundamental issue that needs addressing]
## Recommended Investigation Areas
- specific files to examine
- components to test
- systems to verify
Investigation Principles
- Avoid solution bias - focus on understanding before fixing
- Gather evidence - don't assume, verify with data
- Consider multiple causes - issues often have multiple contributing factors
- Document findings - clear documentation prevents repeat issues
- Think systemically - consider broader implications
- Question assumptions - challenge "it should work" thinking
- Use version control - check when issue was introduced
What ships with it
2 files 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.
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.
- 11d ago First seen · 118 lines · 53 tokens per session scan A eaeaeb08e6e1
root-cause-investigator is a skill published in the GitHub repository umputun/cc-thingz (471 stars, last pushed 2d ago), licensed MIT. It adds 53 tokens to every session and 745 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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