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 agentmods add skills/jpm1118/threadwork/root-cause-tracingnpx skills add JPM1118/Threadwork --skill root-cause-tracinggit clone --depth 1 https://github.com/JPM1118/ThreadworkWhat 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 | $0.00000 | $0.01966 |
| Opus 5 | $0.00000 | $0.00983 |
| Sonnet 5 | $0.00000 | $0.00393 |
| Haiku 4.5 | $0.00000 | $0.00197 |
Grade A, and why
root-cause-tracing 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 2d 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 — 313 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Root Cause Tracing Skill
Fix problems at their source rather than at symptom locations. This skill complements systematic-debugging with deeper investigation techniques.
Core Principle
NEVER TREAT THE SYMPTOM—FIX THE SOURCE
The place where an error manifests is rarely where it originates. Trace backward to find the true cause.
When to Use This Skill
Use this skill when:
- An error occurs but the fix location isn't obvious
- You've fixed a bug but similar bugs keep appearing
- The error message points to framework/library code
- Multiple symptoms seem related
- The bug is in code you didn't write
The Backward Tracing Process
┌─────────────────────────────────────────────────────────────┐
│ Root Cause Tracing Flow │
├─────────────────────────────────────────────────────────────┤
│ │
│ SYMPTOM │
│ ↓ │
│ "What called this?" │
│ ↓ │
│ "What called that?" │
│ ↓ │
│ "What called that?" │
│ ↓ │
│ ROOT CAUSE │
│ ↓ │
│ FIX AT SOURCE │
│ ↓ │
│ ADD DEFENSE-IN-DEPTH │
│ │
└─────────────────────────────────────────────────────────────┘
Step 1: Identify the Symptom
What exactly is happening?
# Get the full error with stack trace
npm test 2>&1 | tee error.log
# Read the COMPLETE stack trace
cat error.log
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.
- 2d ago First seen · 313 lines · 0 tokens per session scan A b6f7acaba280
root-cause-tracing is a skill published in the GitHub repository JPM1118/Threadwork (5 stars, last pushed 8mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,966 tokens. 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 2026-08-31.
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