# Root Cause Debugger

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- **Type:** Skill
- **Install:** `agentstack add skill-pinexai-claude-code-skills-root-cause-debugger`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [pinexai](https://agentstack.voostack.com/s/pinexai)
- **Installs:** 0
- **Category:** [Developer Tools](https://agentstack.voostack.com/c/developer-tools)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [pinexai](https://github.com/pinexai)
- **Source:** https://github.com/pinexai/claude-code-skills/tree/main/root-cause-debugger

## Install

```sh
agentstack add skill-pinexai-claude-code-skills-root-cause-debugger
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Root Cause Debugger

## When this fires

The default failure mode when fixing a bug is to patch whatever line the
stack trace points at until the symptom disappears, without ever confirming
that's actually the cause. That produces fixes that don't hold — the bug
comes back in a different form, or the real cause is still live elsewhere.
This skill forces a differential diagnosis: reproduce, form multiple
hypotheses, gather evidence, and confirm the cause *before* writing a single
line of fix.

## Protocol

1. **Reproduce it.** Get the failure to happen on demand. If it can't be
   reproduced, say so explicitly and state what evidence you're working from
   instead (logs, a single report, a stack trace with no repro steps) —
   don't proceed as if you'd confirmed it.
2. **Localize.** Use `git log` / `git blame` / bisection against recent
   diffs to narrow where the behavior changed, especially for regressions.
   For failures with no clear recent change, localize by narrowing the
   reproduction (smallest input, smallest code path that still fails).
3. **Form at least two hypotheses** for the cause. A single hypothesis
   pursued immediately is exactly the symptom-patching this skill exists to
   prevent.
4. **Gather evidence for and against each hypothesis** — add logging, use a
   debugger, read the actual code path, check inputs/state at the failure
   point. Evidence must be observed, not assumed.
5. **Verify the cause** before writing any fix. The winning hypothesis
   should be one you can state as a mechanism: "X happens because Y, which
   causes Z" — not "it's probably something in this area."
6. **Fix, then confirm the reproduction is gone.** Re-run the exact
   reproduction from step 1. A fix that wasn't verified against the original
   repro isn't confirmed.

## Hard rules

- Never write a fix before stating an evidence-backed root cause. "This
  might help" is not a root cause.
- If the cause can't be confirmed with available evidence, say so plainly
  instead of guessing and presenting the guess as diagnosed.
- A regression must be localized to a change (commit, dependency bump,
  config change) wherever the history makes that possible — "no idea when
  this started" is a last resort, not a first move.
- The fix must address the mechanism identified in step 5, not just make
  the visible symptom stop.

## Output

Before any code is changed, state:

```
Reproduction: 
Localization: 
Hypotheses considered:
  1.  — 
  2.  — 
Root cause: 
```

Then apply the fix, and report the reproduction re-run result (pass/fail)
against the original repro from step 1.

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [pinexai](https://github.com/pinexai)
- **Source:** [pinexai/claude-code-skills](https://github.com/pinexai/claude-code-skills)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-pinexai-claude-code-skills-root-cause-debugger
- Seller: https://agentstack.voostack.com/s/pinexai
- Browse the marketplace: https://agentstack.voostack.com/browse

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