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 rules/dasomel/oh-my-cursor/performancegit clone --depth 1 https://github.com/dasomel/oh-my-cursorWhat 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 | $0.00294 |
| Opus 5 | $0.00000 | $0.00147 |
| Sonnet 5 | $0.00000 | $0.00059 |
| Haiku 4.5 | $0.00000 | $0.00029 |
Grade A, and why
performance 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 yesterday.
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
Performance Standards
Database
- N+1 queries: Always batch-load related records
- Use database-level pagination (LIMIT/OFFSET or cursor-based)
- Index foreign keys and frequently-queried columns
- Avoid
SELECT *— specify needed columns
Caching
- Cache expensive computations (memoization for pure functions)
- Cache HTTP responses where appropriate (ETags, Cache-Control)
- Invalidate cache on data mutation
- Don't cache sensitive or user-specific data globally
Frontend (React/UI)
- Avoid unnecessary re-renders (
useMemo,useCallbackfor stable references) - Lazy-load routes and heavy components
- Virtualize long lists (>100 items)
- Avoid inline object/function creation in JSX
Async Operations
- Run independent async operations in parallel:
await Promise.all([...]) - Don't
awaitinside loops for independent operations - Set timeouts on external calls
- Handle backpressure in streams
Bundle Size
- Check bundle size impact before adding dependencies
- Tree-shake unused code
- Use dynamic imports for large libraries used infrequently
Measurement
- Measure before optimizing (don't guess)
- Profile in production conditions (not dev mode)
- Set performance budgets and enforce in CI
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.
- yesterday First seen · 42 lines · 0 tokens per session scan A 83658f8487ab
performance is a cursor rule published in the GitHub repository dasomel/oh-my-cursor (2 stars, last pushed 5mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 294 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 2026-08-31.
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