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 levnikolaevich/claude-code-skills --skill ln-44-performance-optimizergit clone --depth 1 https://github.com/levnikolaevich/claude-code-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/levnikolaevich/claude-code-skills/ln-44-performance-optimizer)<a href="https://agentmods.dev/skills/levnikolaevich/claude-code-skills/ln-44-performance-optimizer"><img src="https://agentmods.dev/badge/skills/levnikolaevich/claude-code-skills/ln-44-performance-optimizer/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/levnikolaevich/claude-code-skills/ln-44-performance-optimizer"><img src="https://agentmods.dev/badge/skills/levnikolaevich/claude-code-skills/ln-44-performance-optimizer.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 | $0.00021 | $0.02638 |
| Opus 5.5 | $0.00008 | $0.01055 |
| Sonnet 5.5 | $0.00004 | $0.00528 |
| Haiku 4.5 | $0.00002 | $0.00264 |
Grade A, and why
ln-44-performance-optimizer 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 7d 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.
How it starts
The opening of the file, as written. The whole thing — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Performance Optimizer
Goal: Optimize only measured problems. Preserve correctness, isolate experiments, and retain a change only when comparable evidence shows that it improves the agreed metric without unacceptable regressions.
Execution contract: The checklist defines completion. Track each item internally as PENDING, PROVEN with evidence, CLEARED with evidence its condition is absent, or UNPROVEN with a gap; reading, delegation, tool failure, a zero exit status, or a self-reported success is not proof; only the observed outcome is. Reconcile after each section. Before returning, resolve all PENDING, count only PROVEN and CLEARED, and apply verdict and approval rules to every gap.
Preserve intent, scope, and existing authorization. Continue authorized work; ask only for consequential unresolved choices or required external approval. When no one can answer during the run, state the exact question and apply the skill's verdict for the remaining gap instead of waiting or guessing. Scale depth to material risk without skipping checks. Preserve dependency and safety order; otherwise choose an appropriate verification method.
Accept equivalent user or repository evidence; no other skill, named artifact, or complete lifecycle is required. Preserve source requirement and decision IDs. Bind reused evidence to relevant source versions, dirty changes, configuration, and environment; invalidate only affected claims.
On continuation, reconcile task, authorization, current state, and unresolved evidence. For long work, return a compact continuation record or update an already authorized artifact; read-only skills do not persist it. Distinguish artifact readiness, verified behavior, and external-action authority.
Prepare authorized work before required approval. If blocked by an instruction, cite its exact source and unresolved boundary; do not invent approval gates from caution.
Tool Routing
| Need | Preferred tool | Use it when | Fallback |
|---|---|---|---|
| Repository state and safe edit boundary | Git status, diff, branch or worktree inspection, and repository instructions | Always before profiling or editing | Stop if user changes cannot be isolated safely |
| Baseline and final metric | Existing benchmark, load test, reproducible command, or production-like replay | The metric and workload reflect the reported problem | Create the smallest local benchmark that reproduces the behavior without inventing production scale |
| Bottleneck evidence | Existing profiler, tracing, query diagnostics, allocation tools, or OS-level metrics | Locating CPU, memory, I/O, lock, query, network, or scheduler cost | Targeted instrumentation with cleanup plan |
| Code path and blast radius | Language server or host-native code intelligence | Following hot symbols, callers, implementations, and affected contracts | Narrow search plus direct inspection of definitions and consumers |
| Correctness and regressions | Repository-defined tests, build, lint, type, and smoke commands | Before and after every retained experiment | Choose the smallest portfolio action when current evidence cannot detect the likely material regression |
| Runtime and dependency semantics | Official documentation, release notes, and specifications matching installed versions | A hypothesis depends on optimizer, runtime, database, framework, or library behavior | Primary-source web research; otherwise mark the hypothesis UNVERIFIED |
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.
- 7d ago Changed 9c336ef3a209
- 23d ago Changed d9311f3bcdda
- 27d ago First seen · 112 lines · 21 tokens per session scan A f434ce9a74cf
ln-44-performance-optimizer is a skill published in the GitHub repository levnikolaevich/claude-code-skills (573 stars, last pushed 4d ago), licensed MIT. It adds 21 tokens to every session and 2,638 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-09-13.
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