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.
npx agentmods add agents/stefanthecode/dotnet-ai-toolkit/legacy-modernization-assistant.usagegit clone --depth 1 https://github.com/StefanTheCode/dotnet-ai-toolkitWhat 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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00000 | $0.00413 |
| Opus 5 | $0.00000 | $0.00206 |
| Sonnet 5 | $0.00000 | $0.00083 |
| Haiku 4.5 | $0.00000 | $0.00041 |
Grade A, and why
legacy-modernization-assistant.USAGE 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.
What it actually says
How to use — Legacy Modernization Assistant (agent)
What it is. An agent that assesses a legacy .NET codebase and produces a pragmatic, incremental modernization roadmap (strangler-fig, not big-bang) — platform, architecture, DI, async, testability — sequenced by risk and value.
When to reach for it. Modernizing legacy code, migrating off .NET Framework, or "where do I even start with this old codebase".
How to use it. Point it at the codebase (path or GitHub URL). Example prompts:
- "Assess this legacy app and give me a modernization roadmap."
- "We're on .NET Framework — how do we move to modern .NET incrementally?"
- "Where do I start untangling this monolith?"
Get the best out of it. Decide the destination with it first — consolidate on .NET Framework 4.8 (modern tooling, same runtime) or port to modern .NET — because that changes which blockers matter. It runs a concrete .NET Framework blocker scan (System.Web, WCF, Remoting, BinaryFormatter, packages.config, classic csproj) and then hands the actual edits to the right skill: legacy-package-migrator (packages.config → Central Package Management), adonet-data-access-auditor (classic ADO.NET), winforms-maintainer (WinForms fixes), plus dotnet-upgrade-agent, modular-monolith-generator, test-coverage-gap-finder, and async-await-auditor.
Try it on the sample. examples/legacy-pack/ ships a deliberately-broken .NET Framework solution — point the agent at it and compare against examples/legacy-pack/VALIDATION-REPORT.md.
Won't do. It won't recommend a big-bang rewrite unless there's strong justification — incremental is the default. It plans and sequences; the skills make the edits, one project per PR.
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.
- 2d ago First seen · 17 lines · 0 tokens per session scan A 01e5eaeb648b
legacy-modernization-assistant.USAGE is an agent published in the GitHub repository StefanTheCode/dotnet-ai-toolkit (19 stars, last pushed 24d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 413 tokens. 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.
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