code-investigate

code-investigate is a skill for Claude Code from rp1-run/rp1. It costs 31 tokens per session (831 once invoked), scanned A, original, Apache-2.0.

A structured bug-investigation workflow that examines evidence, tests possible explanations, and documents likely root causes without changing the code permanently.

In plain words
What is it for?
Use it to investigate a reported issue, compare hypotheses with evidence, and produce a documented root-cause report.
Why use it?
It helps replace guesswork with a recorded analysis of what is happening and why. This is useful when a bug is difficult to reproduce or has several possible causes.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: mentions subagents.

Part of the rp1-dev plugin — 23 skills, 36 agents shipped together

Good fit Use it to investigate a reported issue, compare hypotheses with evidence, and produce a documented root-cause report.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/rp1-run/rp1/code-investigate
Install

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.

Any agent
npx skills add rp1-run/rp1 --skill code-investigate
Clone the repo
git clone --depth 1 https://github.com/rp1-run/rp1

Made for: Claude Code.

Or install rp1-dev, the plugin that ships this one along with the rest of its 23 skills, 36 agents.

Wrote 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.

agentmods badge for code-investigate

README.md
[![agentmods](https://agentmods.dev/badge/skills/rp1-run/rp1/code-investigate/github.svg)](https://agentmods.dev/skills/rp1-run/rp1/code-investigate)
Your own site
<a href="https://agentmods.dev/skills/rp1-run/rp1/code-investigate"><img src="https://agentmods.dev/badge/skills/rp1-run/rp1/code-investigate/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.

agentmods 80×15 button for code-investigate

Your own site · 80×15
<a href="https://agentmods.dev/skills/rp1-run/rp1/code-investigate"><img src="https://agentmods.dev/badge/skills/rp1-run/rp1/code-investigate.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 31 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 831 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00031 $0.00831
Opus 5.5 $0.00012 $0.00332
Sonnet 5.5 $0.00006 $0.00166
Haiku 4.5 $0.00003 $0.00083

Measured 1mo ago against content hash d0c90d07f08d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

code-investigate 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 1mo 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.

plugins/dev/skills/code-investigate/SKILL.md · 108 lines

How it starts

The opening of the file, as written. The whole thing — 108 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Root Cause Investigator

This command invokes the bug-investigator sub-agent for systematic issue analysis of the provided problem statement.

Before invoking the sub-agent or registering artifacts, derive EFFECTIVE_ISSUE_ID:

  • If ISSUE_ID is non-empty, use it unchanged.
  • Otherwise derive a deterministic lowercase kebab-case slug from PROBLEM_STATEMENT.
  • Collapse repeated separators, trim leading/trailing -, and if the slug would be empty use investigation.

Use EFFECTIVE_ISSUE_ID consistently for workspace paths, report paths, and agent inputs.

First emit: Generate RUN_ID as a UUID. Derive RUN_NAME from the problem statement: a brief summary (max 60 chars) prefixed with "Investigate: ".

On session start, emit the status change:

rp1 agent-tools emit \
  --workflow code-investigate \
  --type status_change \
  --run-id {RUN_ID} \
  --name "Investigate: {brief summary}" \
  --step investigating \
  --data '{"status": "running"}'

STATE-MACHINE

stateDiagram-v2
    [*] --> investigating
    investigating --> [*] : done

Invoke the bug-investigator agent with the freeform problem statement and derived issue id:

{% dispatch_agent "rp1-dev:bug-investigator" %} PROBLEM_STATEMENT={PROBLEM_STATEMENT}, ISSUE_ID={EFFECTIVE_ISSUE_ID}, KB_ROOT={kbRoot}, WORK_ROOT={workRoot} {% enddispatch_agent %}

The agent will:

  • Analyze problem statement and gather context
  • Form and test hypotheses systematically
  • Add temporary debugging (tracked and reverted)
  • Trace code execution paths
  • Identify root cause with evidence
  • Generate comprehensive investigation report
  • Propose solutions with effort estimates
  • Report back with findings

Emit btw_update events for key findings during the investigation:

rp1 agent-tools emit \
  --workflow code-investigate \
  --type btw_update \
  --run-id {RUN_ID} \
  --data '{"message": "{finding summary}"}'

After the agent writes the investigation report, register it as an artifact:

rp1 agent-tools emit \
  --workflow code-investigate \
  --type artifact_registered \
  --run-id {RUN_ID} \
  --step investigating \
  --data '{"path": "issues/{EFFECTIVE_ISSUE_ID}/investigation_report.md", "storageRoot": "work_dir", "format": "markdown"}'

Read the full file on GitHub · 108 lines

Changes

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.

  1. 1mo ago First seen · 108 lines · 31 tokens per session scan A d0c90d07f08d

Subscribe to this mod's changes

code-investigate is a skill published in the GitHub repository rp1-run/rp1 (38 stars, last pushed today), licensed Apache-2.0. It adds 31 tokens to every session and 831 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-09-07.

Related

Other skills, from other repositories

oracle-debug

Disciplined debugging methodology. Triggers on bug reports, test failures, "debug this", "diagnose this", unexpected behavior, build failures, integration issues, or performance regressions. Find root cause before a permanent corrective fix; contain urgent harm safely first.

martinffx/atelier · 56 tokens

doubt-driven-development

Subjects every non-trivial decision to a fresh-context adversarial review before it stands. Use when correctness matters more than speed, when working in unfamiliar code, when stakes are high (production, security-sensitive logic, irreversible operations), or any time a confident output would be cheaper to verify now…

HK-hub/AgentSkills · 67 tokens

audit

Run technical quality checks across accessibility, performance, theming, responsive design, and anti-patterns. Generates a scored report with P0-P3 severity ratings and actionable plan. Use when the user wants an accessibility check, performance audit, or technical quality review.

HK-hub/AgentSkills · 54 tokens

debugging-and-error-recovery

Guides systematic root-cause debugging. Use when tests fail, builds break, behavior doesn't match expectations, or you encounter any unexpected error. Use when you need a systematic approach to finding and fixing the root cause rather than guessing.

HK-hub/AgentSkills · 53 tokens

database-optimizer

Optimizes database queries and improves performance across PostgreSQL and MySQL systems. Use when investigating slow queries, analyzing execution plans, or optimizing database performance. Invoke for index design, query rewrites, configuration tuning, partitioning strategies, lock contention resolution.

HK-hub/AgentSkills · 54 tokens

ai-slop-cleaner

Clean AI-generated code slop with a regression-safe, deletion-first workflow and optional reviewer-only mode.

Yeachan-Heo/oh-my-claudecode · 25 tokens