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Skills juliusbrussee/caveman Caveman

investigate-first

Use it when
something fails and the cause is unclear: an intermittent bug, an odd behavior or a performance regression
It does
separates what was observed from what's guessed, and weighs each explanation by its evidence and by how cheap it is to test
You get
the cause and the evidence for it, or the exact blocker, with no code changed unless the task asks for a fix
Unlike surgical-patch
which goes on to fix the bug, this stops at the diagnosis
Runs
on its own, whenever the agent sees a task that fits; it's a short list of rules, not a step-by-step guide

Skill 8 of 12 in the Caveman bundle · Before it: cavecrew · After it: lean-build

TLDR

The agent touches no product code until the problem is understood. It keeps the observed symptom apart from the cause it suspects, and traces inputs, state changes, which part of the code is responsible for what, and the failure output. It ranks its hypotheses by the evidence for them and by how cheaply each could be ruled out, and won't edit anything until one explanation accounts for all the evidence. It stops exploring once it can name the cause or the exact thing blocking it, and reports the cause with its proof.

Summarizes the skill at bad48a0.

npx skills add https://github.com/juliusbrussee/caveman --skill investigate-first
Installs
61,966 on skills.sh, Sep 21, 2026
Repo stars
106,976 juliusbrussee/caveman
First seen
Aug 11, 2026 on skills.sh
Weekly installs
13.2K
week to Sep 21
Weekly values
Week toInstalls
Aug 30
Aug 100
Aug 176,309
Aug 248,930
Aug 319,022
Sep 711,129
Sep 1412,577
Sep 2113,222
Category

Find root causes, review code and test what you built.

Everything for building software: planning, coding, debugging, design, frameworks, cloud, agents and skills.

Type

A multi-step process the agent follows: interview, debug, run a TDD loop, review.

Effect

Adds no side effects of its own. It shapes how the agent thinks, writes or reviews. Guidelines and routers are always effect:none, even when the task they support edits code.

Needs

Instructions only. Works in any agent that supports skills.

Publisher

Everyone else. Unverified vendor claims default to community.

Topics

SKILL.md

From juliusbrussee/caveman at bad48a0. Checked daily, last changed Oct 20, 2026.

Frontmatter
name: investigate-first
description: Diagnose ambiguous failures before editing. Use for unknown causes, intermittent behavior, performance regressions, or investigations needing evidence-ranked hypotheses.

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.