cursorrules

A set of Cursor rules for the prompt-challenges project. It documents the project, its technology choices, coding conventions, and file-naming rules.

In plain words
What is it for?
Use it when asking Cursor to work on the prompt-challenges codebase and you want it to follow the project’s documented structure and style.
Why use it?
It gives Cursor consistent project-specific guidance, so generated or edited code is more likely to follow the repository’s conventions.

Cursor rule for Cursor

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.

agentmods
npx agentmods add rules/erweixin/prompt-challenges/cursorrules
Clone the repo
git clone --depth 1 https://github.com/erweixin/prompt-challenges

Made for: Cursor.

Per session 1,498 This file is loaded in full into every session.
When invoked 1,498 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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 $0.01498 $0.01498
Opus 5 $0.00749 $0.00749
Sonnet 5 $0.00300 $0.00300
Haiku 4.5 $0.00150 $0.00150

Measured 2d ago against content hash 3ea7b1a04908, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

cursorrules 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 2d 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.

.cursorrules · 238 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

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. 2d ago First seen · 238 lines · 1,498 tokens per session scan A 3ea7b1a04908

Subscribe to this mod's changes

cursorrules is a cursor rule published in the GitHub repository erweixin/prompt-challenges (50 stars, last pushed 4mo ago), with no licence file. It adds 1,498 tokens to every session, about $0.0075 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.