migration-scoring

A review tool for completed code migrations, where software is moved from one codebase or technology to another. It compares the source and target, scores coverage, correctness, and style, and produces a report.

In plain words
What is it for?
Use it to map source files to target files, evaluate migration quality, and get recommendations for improvements.
Why use it?
It helps reveal missing files, incorrect changes, and inconsistent code after a migration.

Skill for Claude CodeCodex

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 skills/openhands/extensions/migration-scoring
Any agent
npx skills add OpenHands/extensions --skill migration-scoring
Clone the repo
git clone --depth 1 https://github.com/OpenHands/extensions

Made for: Claude Code, Codex.

Per session 24 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 857 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00024 $0.00857
Opus 5 $0.00012 $0.00428
Sonnet 5 $0.00005 $0.00171
Haiku 4.5 $0.00002 $0.00086

Measured 2d ago against content hash 46764ec6b66b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

migration-scoring 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 2d 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/migration-scoring/skills/migration-scoring/SKILL.md · 138 lines

How it starts

The opening of the file, as written. The whole thing — 138 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Comprehensive quality evaluation for code migration projects.

Overview

This plugin evaluates completed migrations through multiple lenses:

  1. Mapping — Document source-to-target file relationships
  2. Quality Scoring — Measure coverage and correctness
  3. Style Scoring — Evaluate code quality and conventions
  4. Reporting — Generate executive summary with recommendations

Prerequisites

  • Completed migration with both source and target code present
  • Python 3.13 with uv
  • LLM API key (Anthropic or OpenAI)
  • Optional: Custom style rubric file

Quick Start

export LLM_API_KEY="your-api-key"
export LLM_MODEL="anthropic/claude-3-5-sonnet-20241022"

uv run python -m lc_sdk_examples.migration_scoring \
  --src-path /path/to/migration/project \
  --rubric-path /path/to/style_rubric.txt

PowerShell equivalent for the environment setup:

$env:LLM_API_KEY = "your-api-key"
$env:LLM_MODEL = "anthropic/claude-3-5-sonnet-20241022"

uv run python -m lc_sdk_examples.migration_scoring `
  --src-path C:\path\to\migration\project `
  --rubric-path C:\path\to\style_rubric.txt

Workflow Phases

Phase 1: Migration Mapping

See ../migration-mapping/SKILL.md

Creates a source→target file mapping:

  • Identifies which target files implement each source file
  • Supports many-to-many relationships
  • Flags unmigrated source files

Output: migration_mapping.json

{
  "CALC001.cbl": ["InvoiceCalculator.java", "TaxCalculator.java"],
  "CUST002.cbl": ["CustomerService.java"]
}

Phase 2: Quality Scoring

See ../score-quality/SKILL.md

Scores each source file on:

  • Coverage (1-5): How much functionality was migrated
  • Correctness (1-5): How accurately behavior was preserved

Output: migration_score.json

{
  "CALC001.cbl": {
    "coverage": 4,
    "correctness": 5,
    "justification": "All calculation logic migrated..."
  }
}

Phase 3: Style Scoring

Read the full file on GitHub · 138 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. 2d ago First seen · 138 lines · 24 tokens per session scan A 46764ec6b66b

Subscribe to this mod's changes

migration-scoring is a skill published in the GitHub repository OpenHands/extensions (137 stars, last pushed 4d ago), licensed MIT. It adds 24 tokens to every session and 857 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 2026-08-30.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

next-cache-components-adoption

Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…

vercel/next.js · 95 tokens

babysit-pr

Babysit a GitHub pull request after creation by continuously polling review comments, CI checks/workflow runs, and mergeability state until the PR is merged/closed or user help is required. Diagnose failures, retry likely flaky failures up to 3 times, auto-fix/push branch-related issues when appropriate, and keep…

openai/codex · 114 tokens

imagegen

Generate or edit raster images when the task benefits from AI-created bitmap visuals such as photos, illustrations, textures, sprites, mockups, or transparent-background cutouts. Use when Codex should create a brand-new image, transform an existing image, or derive visual variants from references, and the output…

openai/codex · 113 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens

next-cache-components-optimizer

Drive a Next.js route to instant navigation by setting up an agentic loop, under Cache Components / PPR, on initial load (hard navigation) and client-side navigation (soft navigation). Encode the goal as a failing @next/playwright instant() e2e and work it to green, one verified route at a time; the shipped test then…

vercel/next.js · 170 tokens