modernize-reimagine

modernize-reimagine is a command for Claude Code from ronmkr/PromptBook. It costs 21 tokens per session (848 once invoked), scanned A, original, Apache-2.0.

A multi-agent command for rebuilding an older system as a new, AI-focused system rather than copying its code structure.

In plain words
What is it for?
It extracts business rules, external interfaces, and domain entities, then creates a specification for designing, scaffolding, and validating the replacement.
Why use it?
It separates the original system's intended behavior from its outdated implementation and includes human review points before major decisions.

Command for Claude Code

Written for Claude Code: argument-hint in frontmatter. Also seen: positional $N argument; mentions Gemini CLI.

Good fit It extracts business rules, external interfaces, and domain entities, then creates a specification for designing, scaffolding, and validating the replacement.

Compare 6 commands from other repositories ↓
Install with agentmods
npx agentmods add commands/ronmkr/promptbook/modernize-reimagine
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.

Clone the repo
git clone --depth 1 https://github.com/ronmkr/PromptBook

Made for: Claude Code.

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 modernize-reimagine

README.md
[![agentmods](https://agentmods.dev/badge/commands/ronmkr/promptbook/modernize-reimagine/github.svg)](https://agentmods.dev/commands/ronmkr/promptbook/modernize-reimagine)
Your own site
<a href="https://agentmods.dev/commands/ronmkr/promptbook/modernize-reimagine"><img src="https://agentmods.dev/badge/commands/ronmkr/promptbook/modernize-reimagine/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 modernize-reimagine

Your own site · 80×15
<a href="https://agentmods.dev/commands/ronmkr/promptbook/modernize-reimagine"><img src="https://agentmods.dev/badge/commands/ronmkr/promptbook/modernize-reimagine.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 21 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 848 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 $0.00021 $0.00848
Opus 5 $0.00010 $0.00424
Sonnet 5 $0.00004 $0.00170
Haiku 4.5 $0.00002 $0.00085

Measured 10d ago against content hash 7380384ccdb0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

modernize-reimagine 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 10d 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/standard/code-modernization/commands/modernize-reimagine.md · 84 lines

How it starts

The opening of the file, as written. The whole thing — 84 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Reimagine legacy/$1 as: $2

This is not a port — it's a rebuild from extracted intent. The legacy system becomes the specification source, not the structural template. This command orchestrates a multi-agent team with explicit human checkpoints.

Phase A — Specification mining (parallel agents)

Spawn concurrently and show the user that all three are running:

  1. business-rules-extractor — "Extract every business rule from legacy/$1 into Given/When/Then form. Output to a structured list I can parse."

  2. legacy-analyst — "Catalog every external interface of legacy/$1: inbound (screens, APIs, batch triggers, queues) and outbound (reports, files, downstream calls, DB writes). For each: name, direction, payload shape, frequency/SLA if discernible."

  3. legacy-analyst — "Identify the core domain entities in legacy/$1 and their relationships. Return as an entity list + Mermaid erDiagram."

Collect results. Write analysis/$1/AI_NATIVE_SPEC.md containing:

  • Capabilities (what the system must do — derived from rules + interfaces)
  • Domain Model (entities + erDiagram)
  • Interface Contracts (each external interface as an OpenAPI fragment or AsyncAPI fragment)
  • Non-functional requirements inferred from legacy (batch windows, volumes)
  • Behavior Contract (the Given/When/Then rules — these are the acceptance tests)

Phase B — HITL checkpoint #1

Present the spec summary. Ask the user one focused question: "Which of these capabilities are P0 for the reimagined system, and are there any we should deliberately drop?" Wait for the answer. Record it in the spec.

Phase C — Architecture (single agent, then critique)

Design the target architecture for "$2":

  • Mermaid C4 Container diagram
  • Service boundaries with rationale (which rules/entities live where)
  • Technology choices with one-line justification each
  • Data migration approach from legacy stores

Then spawn architecture-critic: "Review this proposed architecture for $2 against the spec in analysis/$1/AI_NATIVE_SPEC.md. Identify over-engineering, missed requirements, scaling risks, and simpler alternatives." Incorporate the critique. Write the result to analysis/$1/REIMAGINED_ARCHITECTURE.md.

Read the full file on GitHub · 84 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. 10d ago First seen · 84 lines · 21 tokens per session scan A 7380384ccdb0

Subscribe to this mod's changes

modernize-reimagine is a command published in the GitHub repository ronmkr/PromptBook (2 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 21 tokens to every session and 848 once invoked, about $0.0001 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 2026-08-31.