Borrowing it
Nothing to install: this file belongs to veryfront/veryfront-code. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/veryfront/veryfront-code/main/.claude/skills/vf-performance/SKILL.mdgit clone --depth 1 https://github.com/veryfront/veryfront-codeWrote 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/veryfront/veryfront-code/vf-performance)<a href="https://agentmods.dev/skills/veryfront/veryfront-code/vf-performance"><img src="https://agentmods.dev/badge/skills/veryfront/veryfront-code/vf-performance/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/veryfront/veryfront-code/vf-performance"><img src="https://agentmods.dev/badge/skills/veryfront/veryfront-code/vf-performance.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00033 | $0.02358 |
| Opus 5.5 | $0.00013 | $0.00943 |
| Sonnet 5.5 | $0.00007 | $0.00472 |
| Haiku 4.5 | $0.00003 | $0.00236 |
Grade A, and why
vf-performance scanned grade A with 1 finding 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 2mo 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
time curl -s -o /dev/null http://localhost:3000/ How it starts
The opening of the file, as written. The whole thing — 300 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Veryfront Performance Review & Benchmark
Overview
This skill covers performance analysis across all layers of veryfront: runtime hot paths, request latency, build/compile time, and bundle size. Use it to identify regressions before they ship and to measure the impact of optimizations.
Core principle: Measure first, optimize second. Never optimize without a baseline.
When to Use
- Before merging performance-sensitive PRs
- When investigating latency complaints or slowdowns
- After adding new middleware, transforms, or rendering paths
- When modifying hot paths (SSR, data fetching, API routing, transforms)
- When adding dependencies or changing build configuration
Part 1: Performance Review Checklist
Run through this checklist when reviewing code for performance. Flag items that apply.
Runtime Hot Paths
| Pattern | Risk | Where to Check |
|---|---|---|
| Sync I/O in request path | Blocks event loop | API handlers, middleware, SSR |
await in a loop (N+1) |
Multiplied latency | Data fetchers, module loaders |
Unbounded Promise.all |
Memory spike | Batch operations, parallel fetches |
| Missing cache / cache miss storm | Redundant work | FileCache, module cache, transform cache |
| Regex on untrusted input | ReDoS potential | Route matching, content parsing |
| Large JSON.stringify/parse | CPU spike per request | Request/response serialization, SSR props |
| Module re-import on each request | Startup cost repeated | Worker script, dynamic imports |
| Unnecessary cloning | Memory churn | request.clone(), deep copies |
Memory & Allocation
| Pattern | Risk | Where to Check |
|---|---|---|
| Growing Map/Set without eviction | Memory leak | Caches, registries, module maps |
| Holding large buffers across requests | Heap pressure | SSR streams, file uploads |
| Closures capturing request scope | Prevents GC | Event handlers, callbacks |
new TextEncoder() per call |
Allocation churn | Use module-level singleton |
Accumulating strings via += |
O(n^2) copying | HTML building, log formatting |
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.
- 2mo ago First seen · 300 lines · 33 tokens per session scan A 72749f891862
vf-performance is a skill published in the GitHub repository veryfront/veryfront-code (20 stars, last pushed yesterday), licensed Apache-2.0. It adds 33 tokens to every session and 2,358 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
vf-performance compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| vf-performanceveryfront/veryfront-code | Skill | 20 | yesterday | Apache-2.0 | A | 33 | Claude Code |
| investigateAbyssCN/oh-my-dag | Skill | 44 | 26d ago | MIT | A | 77 | Claude Code, Codex |
| bugfix-triageAbyssCN/oh-my-dag | Skill | 44 | 26d ago | MIT | A | 37 | Claude Code, Codex |
| typescript-testingComposioHQ/composio | Skill | 31k | yesterday | MIT | A | 92 | Claude Code, Codex |
| cli-e2eComposioHQ/composio | Skill | 31k | yesterday | MIT | A | 62 | Claude Code, Codex |
| ios-simulatorcallstack/agent-device | Skill | 5.3k | yesterday | MIT | A | 69 | Claude Code, Codex |
| cvm-ai-doctorTencentCloud/Octop | Skill | 12k | yesterday | MIT | A | 70 | Claude Code, Codex |