ciel-root-cause-debugger

ciel-root-cause-debugger is a skill for Claude Code, Codex from jxoesneon/Ciel. It costs 25 tokens per session (469 once invoked), scanned A, original, Apache-2.0.

A method for finding the underlying cause of a software bug by reproducing it, examining execution data, and testing the fix. It treats logs, errors, and test results as evidence rather than relying on guesses.

In plain words
What is it for?
Creating minimal reproductions, tracing errors through code and logs, checking system health, finding performance bottlenecks, applying focused fixes, and running the full test suite.
Why use it?
It prevents changes that only hide symptoms or create new problems. It also encourages adding a regression test so the same bug is less likely to return.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Creating minimal reproductions, tracing errors through code and logs, checking system health, finding performance bottlenecks, applying focused fixes, and running the full test suite.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jxoesneon/ciel/ciel-root-cause-debugger
Install

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.

Any agent
npx skills add jxoesneon/Ciel --skill ciel-root-cause-debugger
Clone the repo
git clone --depth 1 https://github.com/jxoesneon/Ciel

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for ciel-root-cause-debugger

README.md
[![agentmods](https://agentmods.dev/badge/skills/jxoesneon/ciel/ciel-root-cause-debugger.svg)](https://agentmods.dev/skills/jxoesneon/ciel/ciel-root-cause-debugger)
Your own site
<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="Measured on agentmods" height="20"></a>
Per session 25 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 469 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00025 $0.00469
Opus 5 $0.00013 $0.00234
Sonnet 5 $0.00005 $0.00094
Haiku 4.5 $0.00003 $0.00047

Measured 4d ago against content hash c28311b1e8ff, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

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 4d 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.

skills/ciel-root-cause-debugger/SKILL.md · 46 lines

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)

  1. Reproduce: Create a minimal reproduction script or test case. If it doesn't fail, you haven't found the bug.
  2. Trace: Use run_shell_command to execute the code and capture stdout/stderr.
  3. Isolate: Use grep_search to find the failure point in the call stack.
  4. Fix: Apply the minimal change needed to pass the reproduction test.
  5. Verify: Run the entire suite to ensure no regressions.

Tooling Usage

  • Logs: Read logs with read_file or read_background_output. Do not assume log content.
  • System: Use systemctl, journalctl, or docker logs to 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.
Changes

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.

  1. 4d ago First seen · 46 lines · 25 tokens per session scan A c28311b1e8ff

Subscribe to this mod's changes

ciel-root-cause-debugger is a skill published in the GitHub repository jxoesneon/Ciel (1 stars, last pushed today), licensed Apache-2.0. It adds 25 tokens to every session and 469 once invoked, about $0.0001 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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