---
name: juliusbrussee-investigate-first
description: "Diagnose ambiguous failures before editing. Use for unknown causes, intermittent behavior, performance regressions, or investigations needing evidence-ranked hypotheses."
license: "NOASSERTION"
metadata:
  decimalai-skill-id: "4b8b5ba0-1071-475f-b6ba-2ad23f5a6c77"
  decimalai-version-id: "77c7add8-f303-495c-9910-13feb1099bf3"
  decimalai-version: "1"
  decimalai-body-sha256: "c2019e5359293a97e9a0e5b4c1e54b8610ae79d4417ddf6b70cc8aaa3547a72e"
  decimalai-name: "juliusbrussee/investigate-first"
  decimalai-format: "1"
  decimalai-invocation: "model"
  decimalai-category: "coding"
  decimalai-source: "https://app.decimal.ai/s/juliusbrussee-investigate-first@1/SKILL.md"
---
# Investigate first

Gather evidence before changing product code.

- Separate observed symptom from inferred cause.
- Trace inputs, state transitions, ownership boundaries, and failure output.
- Rank hypotheses by evidence and cheap falsification value.
- Do not edit until one credible mechanism explains evidence.
- Stop exploration when evidence is sufficient to name cause or exact blocker.

Report cause and proof. Make no fix unless task authorizes implementation.