pm-claude-skills/plugins/pm-engineering/skills/debugging-log-analyser/SKILL.md

name, description

name	description
debugging-log-analyser	Parse error logs, stack traces, and crash reports into a structured root cause diagnosis. Use when sharing a log, stack trace, error output, or crash dump. Produces a structured diagnosis with probable root cause, affected code path, suggested fix, and next debugging steps. Optimised for Opus 4.7 and newer models.

Debugging Log Analyser Skill

Parses raw error logs, stack traces, and crash reports into a structured diagnosis with probable root cause, affected code path, and specific next steps — no hand-waving.

Required Inputs

Ask for these if not provided:

• The log / stack trace / error output (paste directly or describe the error)
• Language and framework (e.g. Node.js + Express, Python + Django, Java Spring, Go)
• Context (what the user was doing when the error occurred)
• Environment (local dev / staging / production)
• What they've already tried (if anything)

Output Structure

1. Error Classification

Error type: [Runtime exception / Build error / Config error / Network error / Memory/resource error / Unknown] Severity: [Fatal / Critical / Warning / Informational] Recurrence pattern: [One-off / Intermittent / Consistent / On-startup / Under load]

2. Stack Trace Analysis

Walk the stack frame by frame, starting from the origin:

• Origin frame: [File, line, function where it started]
• Propagation path: [How it travelled through the call stack]
• Crash point: [Where it ultimately threw/panicked/exited]

For each significant frame, note whether it is:

• User code (fixable here)
• Framework/library code (usually a misuse issue)
• System/runtime code (usually a config or environment issue)

3. Root Cause Assessment

Probable root cause: [1–2 sentence plain English statement] Confidence: [High / Medium / Low — and why] Alternative causes to rule out: [If confidence is not high]

4. Affected Code Path

Entry point: [Where the triggering call began] Key function(s) involved: [Specific functions/methods named in the trace] Data that triggered it: [If inferable from the log — e.g. null value, malformed JSON]

5. Suggested Fix

Provide a concrete, code-level suggestion:

• What to change (the minimal fix)
• Why this fixes the root cause
• Any trade-offs or risks in the fix
• A short code snippet if helpful

6. Next Debugging Steps

If the root cause is uncertain, provide an ordered list of 3–5 specific debugging actions:

1. [Specific thing to check — file, log line, config value]
2. [Specific reproduction step or isolation test]
3. [Specific tool command — e.g. strace, pprof, --verbose, add logging at X]

7. Prevention

One or two concrete things that would prevent this class of error recurring:

• Better input validation at [point]
• Add monitoring/alerting for [condition]
• Test that covers [scenario]

Quality Checks

• Root cause is specific (not "there might be a null pointer issue")
• At least one concrete code-level fix is suggested
• Next steps are actionable commands, not vague advice
• Language-specific idioms are used correctly
• Prevention is proactive (not just "add error handling")

Example Trigger Phrases

• "Why is this crashing?" + [paste log]
• "Can you analyse this stack trace?"
• "I'm getting this error, what does it mean?"
• "Debug this log for me"
• "What's causing this exception?"