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 arozumenko/sdlc-skills --skill root-cause-analysisgit clone --depth 1 https://github.com/arozumenko/sdlc-skillsWrote 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/arozumenko/sdlc-skills/root-cause-analysis)<a href="https://agentmods.dev/skills/arozumenko/sdlc-skills/root-cause-analysis"><img src="https://agentmods.dev/badge/skills/arozumenko/sdlc-skills/root-cause-analysis/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/arozumenko/sdlc-skills/root-cause-analysis"><img src="https://agentmods.dev/badge/skills/arozumenko/sdlc-skills/root-cause-analysis.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00064 | $0.00994 |
| Opus 5 | $0.00032 | $0.00497 |
| Sonnet 5 | $0.00013 | $0.00199 |
| Haiku 4.5 | $0.00006 | $0.00099 |
Grade A, and why
root-cause-analysis 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 9d 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 — 97 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Root-Cause Analysis (RCA)
Trace a confirmed bug to its exact cause and produce a structured RCA artifact. Investigation only — you do NOT edit code, branch, or fix.
Platform & systems
The RCA report goes on the tracker ticket — the source of truth — using
the tracker scout recorded in .agents/profile.md § Project systems. The
gh issue … commands below are the GitHub reference; translate per
.agents/workflow.md § Git host. With no tracker, report directly to the user.
When to use
Pairs with systematic-debugging — use its rigor (reproduce reliably,
condition-based waiting) to trace, then produce the structured report here.
Methodology — 4 phases
1. Ticket acquisition
Read the ticket and all comments (reproduction steps, errors, stack traces, environment, prior notes). Note that RCA has started on the ticket.
2. Codebase investigation — trace, don't guess
- Locate the entry point: grep the error message / function / route.
- Trace the call chain: entry (route/handler) → service (logic) → data layer → failure point. Read each file in the chain.
- Examine the failure point: which assumption is violated? what input triggers it? is the bug here or in a dependency?
- Search for patterns: how is the function called elsewhere; are there
similar patterns that work;
git blameand recentgit logon the file.
3. Root-cause determination
Classify the cause:
| Category | Description | Example |
|---|---|---|
| Logic | Wrong condition, missing branch, off-by-one | if x > 0 should be if x >= 0 |
| Data | Unexpected input, null handling, type mismatch | Missing null check on optional field |
| Concurrency | Race condition, missing lock, async issue | Two requests mutating the same resource |
| Configuration | Wrong default, missing env var | Timeout too low for large payloads |
| Integration | API contract / dependency version change | Third-party API changed its response shape |
| Resource | Memory, connection pool, file handles | DB connection pool exhausted |
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.
- 9d ago First seen · 97 lines · 64 tokens per session scan A e7cdd5c9d70f
root-cause-analysis is a skill published in the GitHub repository arozumenko/sdlc-skills (20 stars, last pushed 4d ago), licensed MIT. It adds 64 tokens to every session and 994 once invoked, about $0.0003 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 2026-08-30.
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