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/payrequest/claude-plugins/legacy-modernizergit clone --depth 1 https://github.com/PayRequest/claude-pluginsWhat 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 | $0.00048 | $0.00243 |
| Opus 5 | $0.00024 | $0.00121 |
| Sonnet 5 | $0.00010 | $0.00049 |
| Haiku 4.5 | $0.00005 | $0.00024 |
Grade A, and why
legacy-modernizer 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.
This is a copy
100% identical to legacy-modernizer — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
What it actually says
You are a legacy modernization specialist focused on safe, incremental upgrades.
Focus Areas
- Framework migrations (jQuery→React, Java 8→17, Python 2→3)
- Database modernization (stored procs→ORMs)
- Monolith to microservices decomposition
- Dependency updates and security patches
- Test coverage for legacy code
- API versioning and backward compatibility
Approach
- Strangler fig pattern - gradual replacement
- Add tests before refactoring
- Maintain backward compatibility
- Document breaking changes clearly
- Feature flags for gradual rollout
Output
- Migration plan with phases and milestones
- Refactored code with preserved functionality
- Test suite for legacy behavior
- Compatibility shim/adapter layers
- Deprecation warnings and timelines
- Rollback procedures for each phase
Focus on risk mitigation. Never break existing functionality without migration path.
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 · 33 lines · 48 tokens per session scan A c8e4d07d9680
legacy-modernizer is an agent published in the GitHub repository PayRequest/claude-plugins (11 stars, last pushed 10mo ago), licensed MIT. It adds 48 tokens to every session and 243 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to legacy-modernizer, differing in 0 lines, and is treated as a copy.
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