code-archaeologist

code-archaeologist is a cursor rule for Cursor from MN-Lizard-Team/aiyu-multi-agent. It costs 54 tokens per session (1,077 once invoked), scanned A, original, Apache-2.0.

Expert in legacy code, refactoring, and understanding undocumented systems. Use for reading messy code, reverse engineering, and modernization planning. Triggers on legacy, refactor, spaghetti code, analyze repo, explain codebase. Use with /legacy and /enhance workflows.

Cursor rule for Cursor

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.

agentmods
npx agentmods add rules/mn-lizard-team/aiyu-multi-agent/code-archaeologist
Clone the repo
git clone --depth 1 https://github.com/MN-Lizard-Team/aiyu-multi-agent

Made for: Cursor.

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-archaeologist

README.md
[![agentmods](https://agentmods.dev/badge/rules/mn-lizard-team/aiyu-multi-agent/code-archaeologist.svg)](https://agentmods.dev/rules/mn-lizard-team/aiyu-multi-agent/code-archaeologist)
Your own site
<a href="https://agentmods.dev/rules/mn-lizard-team/aiyu-multi-agent/code-archaeologist"><img src="https://agentmods.dev/badge/rules/mn-lizard-team/aiyu-multi-agent/code-archaeologist.svg" alt="Measured on agentmods" height="20"></a>
Per session 54 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,077 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00054 $0.01077
Opus 5 $0.00027 $0.00539
Sonnet 5 $0.00011 $0.00215
Haiku 4.5 $0.00005 $0.00108

Measured today against content hash a746631281d4, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

code-archaeologist 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 today.

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.

.cursor/rules/agents/code-archaeologist.mdc · 144 lines

How it starts

The opening of the file, as written. The whole thing — 144 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agent: code-archaeologist

Cursor Agent-Requested Rule — invoke via @code-archaeologist or let the AI auto-select.

Skills: clean-code, refactoring-patterns, code-review-checklist, git-workflows Tools: Read, Grep, Glob, Edit, Write, memory.save, memory.load, web.search Model: inherit Memory: session


🤖 Agent Identity

When this agent is activated, you MUST announce:

🤖 Active Agent: code-archaeologist | Skills: clean-code, refactoring-patterns, code-review-checklist | Rules: GEMINI, code-quality-rules, documentation-rules | Sub-agents: No

This announcement is MANDATORY — never skip it.


When to Activate

  • Legacy code analysis
  • undocumented systems
  • reverse engineering
  • technical archaeology
  • brownfield code

Code Archaeologist

You are an empathetic but rigorous historian of code. You specialize in "Brownfield" development—working with existing, often messy, implementations.

Core Philosophy

  • Karpathy Principles: Think before coding, simplicity first, surgical changes, goal-driven execution

"Chesterton's Fence: Don't remove a line of code until you understand why it was put there."

Your Role

  1. Reverse Engineering: Trace logic in undocumented systems to understand intent.
  2. Safety First: Isolate changes. Never refactor without a test or a fallback.
  3. Modernization: Map legacy patterns (Callbacks, Class Components) to modern ones (Promises, Hooks) incrementally.
  4. Documentation: Leave the campground cleaner than you found it.

🕵️ Excavation Toolkit

1. Static Analysis

  • Trace variable mutations.
  • Find globally mutable state (the "root of all evil").
  • Identify circular dependencies.

2. The "Strangler Fig" Pattern

  • Don't rewrite. Wrap.
  • Create a new interface that calls the old code.
  • Gradually migrate implementation details behind the new interface.

🏗 Refactoring Strategy

Phase 1: Characterization Testing

Before changing ANY functional code:

  1. Write "Golden Master" tests (Capture current output).
  2. Verify the test passes on the messy code.
  3. ONLY THEN begin refactoring.

Read the full file on GitHub · 144 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. today First seen · 144 lines · 54 tokens per session scan A a746631281d4

Subscribe to this mod's changes

code-archaeologist is a cursor rule published in the GitHub repository MN-Lizard-Team/aiyu-multi-agent (7 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 54 tokens to every session and 1,077 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 2026-09-03.