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 jxoesneon/Ciel --skill ciel-root-cause-debuggergit clone --depth 1 https://github.com/jxoesneon/CielWrote 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/jxoesneon/ciel/ciel-root-cause-debugger)<a href="https://agentmods.dev/skills/jxoesneon/ciel/ciel-root-cause-debugger"><img src="https://agentmods.dev/badge/skills/jxoesneon/ciel/ciel-root-cause-debugger/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/jxoesneon/ciel/ciel-root-cause-debugger"><img src="https://agentmods.dev/badge/skills/jxoesneon/ciel/ciel-root-cause-debugger.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00025 | $0.00354 |
| Opus 5.5 | $0.00010 | $0.00142 |
| Sonnet 5.5 | $0.00005 | $0.00071 |
| Haiku 4.5 | $0.00003 | $0.00035 |
Grade A, and why
ciel-root-cause-debugger 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 28d 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.
What it actually says
CIEL ADAPTATION: Root Cause Debugger (The Scalpel)
This skill formalizes the transition from "guessing" to "empirical evidence" during debugging. it mandates the use of execution data.
Debugging Protocol (RCA)
- Reproduce: Create a minimal reproduction script or test case. If it doesn't fail, you haven't found the bug.
- Trace: Use
run_shell_commandto execute the code and capturestdout/stderr. - Isolate: Use
grep_searchto find the failure point in the call stack. - Fix: Apply the minimal change needed to pass the reproduction test.
- Verify: Run the entire suite to ensure no regressions.
Tooling Usage
- Logs: Read logs with
read_fileorread_background_output. Do not assume log content. - System: Use
systemctl,journalctl, ordocker logsto check environment health. - Profiling: Use
perf,time, or language-specific profilers to identify bottlenecks.
Anti-Patterns
- The Guess-and-Check: Modifying code before reproducing the failure.
- The Silent Swallow: Adding a try-catch block that hides the error instead of fixing the cause.
- Amnesiac Debugging: Fixing a bug without adding a regression test.
What ships with it
1 file 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.
- 28d ago Changed · -13 lines f6db436e1639
- 1mo ago First seen · 46 lines · 25 tokens per session scan A c28311b1e8ff
ciel-root-cause-debugger is a skill published in the GitHub repository jxoesneon/Ciel (1 stars, last pushed 5d ago), licensed Apache-2.0. It adds 25 tokens to every session and 354 once invoked, about $0.0001 per session on Opus 5.5. 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.
Other skills, from other repositories
fix-feature-bug
Fix bugs using structured workflow with error classification and regression tests. Use when user reports bugs, errors, broken features, test failures, or mentions "fix", "broken", "not working", "failing". Can be invoked via /fix-feature-bug.
debugging-test-failures
Systematically investigates failing tests, distinguishes between test bugs and implementation bugs, and drives a fix with verification. Use when the user wants to debug failing tests.
test-fix
Automatically invoke when any test run produces failures: FAIL output, test errors, or assertion failures in unit or E2E suites. Do NOT wait for the user to ask. Hard limit of 3 fix attempts per failure, then stops and escalates. Trigger on: "tests are failing", "fix the tests", "tests are broken".
fix-bug
Use when a ticket reports defective behaviour — a wrong result, a crash, a regression, "X doesn't work when Y" — and the fix must be proven with a test that fails before and passes after. Invoke for any bug, incident follow-up, or "this used to work" ticket before touching the code.
investigate
Systematic debugging with Iron Law methodology. 5-phase investigation from evidence collection to verified fix. Triggers on "investigate", "debug", "root cause".
test-scaffold
Gera estrutura completa de testes automatizados (unitários, integração e edge cases) com base no código existente. Use para "escrever testes para este arquivo", "aumentar cobertura" ou "criar mocks".