Borrowing it
Nothing to install: this file belongs to tellahq/opensession. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/tellahq/opensession/main/.agents/skills/pstack-suite/skills/principle-fix-root-causes/SKILL.mdgit clone --depth 1 https://github.com/tellahq/opensessionWrote 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/tellahq/opensession/principle-fix-root-causes)<a href="https://agentmods.dev/skills/tellahq/opensession/principle-fix-root-causes"><img src="https://agentmods.dev/badge/skills/tellahq/opensession/principle-fix-root-causes.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 | $0.00042 | $0.00294 |
| Opus 5 | $0.00021 | $0.00147 |
| Sonnet 5 | $0.00008 | $0.00059 |
| Haiku 4.5 | $0.00004 | $0.00029 |
Grade A, and why
principle-fix-root-causes 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 3d 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.
Copies of this mod
6 near-identical copies found in the catalogue:
- principle-fix-root-causes — 100% identical, 0 lines differ
- principle-fix-root-causes — 100% identical, 0 lines differ
- principle-fix-root-causes — 95% identical, 2 lines differ
- principle-fix-root-causes — 95% identical, 2 lines differ
- principle-fix-root-causes — 94% identical, 4 lines differ
- principle-fix-root-causes — 92% identical, 3 lines differ
What it actually says
Fix Root Causes
When debugging, do not paper over symptoms. Trace every problem to its root cause and fix it there.
Why: Symptom fixes accumulate. Each workaround makes the system harder to reason about, and the real bug remains. Root-cause fixes are slower upfront but reduce total debugging time.
Pattern:
- Reproduce first (if you can't reproduce it, you can't verify your fix)
- Ask "why" until you hit the root cause
- Resist the urge to add guards (adding a nil check to silence a crash is a symptom fix)
- If a workaround needs a paragraph-long comment to justify it, the code is wrong (fix the code, not the comment)
- Check for the pattern, not just the instance (grep for the same pattern, fix all instances)
- When stuck, instrument. Don't guess (add logging, read the actual error)
Restart bugs: suspect state before code
Code doesn't change between runs. State does. When something "fails after restart," suspect stale persistent state first: config files, caches, lock files, serialized state. If clearing a state file restores behavior, prioritize state validation as the fix.
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.
- 3d ago First seen · 24 lines · 42 tokens per session scan A cfae13b5a3e2
principle-fix-root-causes is a skill published in the GitHub repository tellahq/opensession (355 stars, last pushed yesterday), licensed MIT. It adds 42 tokens to every session and 294 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 2026-09-03.
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