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 michael-denyer/pstack-claude --skill principle-migrate-callers-then-delete-legacy-apisgit clone --depth 1 https://github.com/michael-denyer/pstack-claudeWrote 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/michael-denyer/pstack-claude/principle-migrate-callers-then-delete-legacy-apis)<a href="https://agentmods.dev/skills/michael-denyer/pstack-claude/principle-migrate-callers-then-delete-legacy-apis"><img src="https://agentmods.dev/badge/skills/michael-denyer/pstack-claude/principle-migrate-callers-then-delete-legacy-apis/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/michael-denyer/pstack-claude/principle-migrate-callers-then-delete-legacy-apis"><img src="https://agentmods.dev/badge/skills/michael-denyer/pstack-claude/principle-migrate-callers-then-delete-legacy-apis.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 | $0.00045 | $0.00228 |
| Opus 5 | $0.00023 | $0.00114 |
| Sonnet 5 | $0.00009 | $0.00046 |
| Haiku 4.5 | $0.00005 | $0.00023 |
Grade A, and why
principle-migrate-callers-then-delete-legacy-apis 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 3d 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
88% identical to principle-migrate-callers-then-delete-legacy-apis — 4 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
Migrate Callers Then Delete Legacy APIs
When we decide a new API is the right design, migrate callers and remove the old API in the same refactor wave instead of preserving compatibility layers.
Rule:
- Do not keep legacy API paths only because internal callers still exist
- Inventory callers, migrate them, and delete the old API immediately
- Treat temporary adapters as exceptional and time-boxed, not default architecture
- Update tests to assert the new contract, and delete tests that only protect pre-refactor implementation details
When this applies:
- No external users depend on backward compatibility
- The project can absorb coordinated breaking changes
- The new API is part of a simplification or refactor initiative
Keeping both old and new APIs creates dual-path complexity, slows cleanup, and makes the codebase feel append-only.
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.
- 3d ago Changed 8014f4eb04fe
- 12d ago First seen · 23 lines · 45 tokens per session scan A 14c88d4c3c9c
principle-migrate-callers-then-delete-legacy-apis is a skill published in the GitHub repository michael-denyer/pstack-claude (341 stars, last pushed today), licensed MIT. It adds 45 tokens to every session and 228 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 88% identical to principle-migrate-callers-then-delete-legacy-apis, differing in 4 lines, and is treated as a copy.
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