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 skills add sethdford/claude-skills --skill legacy-modernizationgit clone --depth 1 https://github.com/sethdford/claude-skillsWrote 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.
[](https://agentmods.dev/skills/sethdford/claude-skills/legacy-modernization)<a href="https://agentmods.dev/skills/sethdford/claude-skills/legacy-modernization"><img src="https://agentmods.dev/badge/skills/sethdford/claude-skills/legacy-modernization/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.
<a href="https://agentmods.dev/skills/sethdford/claude-skills/legacy-modernization"><img src="https://agentmods.dev/badge/skills/sethdford/claude-skills/legacy-modernization.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00025 | $0.00225 |
| Opus 5 | $0.00013 | $0.00112 |
| Sonnet 5 | $0.00005 | $0.00045 |
| Haiku 4.5 | $0.00003 | $0.00022 |
Grade A, and why
legacy-modernization 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 12d 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
Legacy Modernization
Modernize legacy systems incrementally using strangler fig pattern, facade layers, and strategic refactoring.
Instructions
- Assessment: Understand current system behavior, pain points
- Strangler Fig: New services alongside old monolith; gradually redirect traffic
- Facade Layer: Wrap legacy with modern API without changing internals
- Refactoring: Extract modules one at a time to modern stack
- Incremental Value: Each phase delivers business value
Anti-Patterns
- Rewrite Everything: "Let's rebuild it right." Result: 2-3 years, misses market. Guard: Keep old system running while new builds alongside.
- No Business Alignment: Modernize things users don't care about. Guard: Modernize parts causing business pain first.
Further Reading
- Monolith to Microservices — specific modernization patterns
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.
- 12d ago First seen · 26 lines · 25 tokens per session scan A 7f257c3d091d
legacy-modernization is a skill published in the GitHub repository sethdford/claude-skills (41 stars, last pushed 6mo ago), licensed MIT. It adds 25 tokens to every session and 225 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.
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