web-vitals-and-sre

web-vitals-and-sre is a cursor rule for Cursor from grafana/grafana-pathfinder-app. It costs 49 tokens per session (1,028 once invoked), scanned A, original, AGPL-3.0.

A set of review rules for React applications covering slow page loading, blocked browser work, layout movement, request chains, browser storage, and competition between external scripts.

In plain words
What is it for?
Use it when reviewing React code for anti-patterns R16–R21 or auditing loading speed and reliability in a live application.
Why use it?
It helps identify common causes of slow or unreliable pages during code review or production performance checks.

Cursor rule for Cursor ✓ vendor

Written for Cursor: installed under .cursor/.

Good fit Use it when reviewing React code for anti-patterns R16–R21 or auditing loading speed and reliability in a live application.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/grafana/grafana-pathfinder-app/web-vitals-and-sre
About the project

grafana-pathfinder-app is a Grafana plugin that adds documentation and guided tutorials inside Grafana's interface. It helps Grafana users find context-relevant help, follow interactive learning paths, and track progress without leaving the application. Its catalogue entries define guidance for using the plugin.

grafana/grafana-pathfinder-app · 19 stars · on GitHub · grafana.com

Install

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.

Clone the repo
git clone --depth 1 https://github.com/grafana/grafana-pathfinder-app

Made for: Cursor.

Wrote 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.

agentmods badge for web-vitals-and-sre

README.md
[![agentmods](https://agentmods.dev/badge/rules/grafana/grafana-pathfinder-app/web-vitals-and-sre/github.svg)](https://agentmods.dev/rules/grafana/grafana-pathfinder-app/web-vitals-and-sre)
Your own site
<a href="https://agentmods.dev/rules/grafana/grafana-pathfinder-app/web-vitals-and-sre"><img src="https://agentmods.dev/badge/rules/grafana/grafana-pathfinder-app/web-vitals-and-sre/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.

agentmods 80×15 button for web-vitals-and-sre

Your own site · 80×15
<a href="https://agentmods.dev/rules/grafana/grafana-pathfinder-app/web-vitals-and-sre"><img src="https://agentmods.dev/badge/rules/grafana/grafana-pathfinder-app/web-vitals-and-sre.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 49 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,028 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00049 $0.01028
Opus 5 $0.00024 $0.00514
Sonnet 5 $0.00010 $0.00206
Haiku 4.5 $0.00005 $0.00103

Measured 12d ago against content hash 2d02bc2d8c4c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

web-vitals-and-sre 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 12d 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.

.cursor/rules/react-antipatterns/web-vitals-and-sre.mdc · 104 lines

The source is not reproduced here

Licensed AGPL-3.0

The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

Changes

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.

  1. 12d ago First seen · 104 lines · 49 tokens per session scan A 2d02bc2d8c4c

Subscribe to this mod's changes

web-vitals-and-sre is a cursor rule published in the GitHub repository grafana/grafana-pathfinder-app (19 stars, last pushed today), licensed AGPL-3.0. It adds 49 tokens to every session and 1,028 once invoked, about $0.0002 per session on Opus 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 2026-08-30.