cursorrules

A set of rules for how an AI coding agent should work in a project. It covers context warnings, requests for missing material, error correction, complete code, comments, validation, strict TypeScript, and string style.

In plain words
What is it for?
Use it to guide TypeScript implementation, error handling, comments, type definitions, string formatting, context-limit warnings, and missing-content requests.
Why use it?
It gives the agent consistent expectations for code quality and communication. It also tells the agent how to respond when the project lacks information or contains terminology errors.

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/smythos/smythos-studio/cursorrules
Clone the repo
git clone --depth 1 https://github.com/SmythOS/smythos-studio

Made for: Cursor.

Per session 255 This file is loaded in full into every session.
When invoked 255 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original 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 $0.00255 $0.00255
Opus 5 $0.00128 $0.00128
Sonnet 5 $0.00051 $0.00051
Haiku 4.5 $0.00026 $0.00026

Measured 2d ago against content hash 24b4bd1b10bf, 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 · 18 lines

What it actually says

OPERATIONAL FEATURES

  • Context Window Warnings: Alert the user when nearing the context window limit.
  • Missing Content Requests: Request the user to provide project code, documentation, or definitions necessary for an adequate response.
  • Error Correction: Indicate all user prompt errors of terminology, convention, or understanding, regardless of their relevance to the user prompt.

CRITICALLY IMPORTANT RULES

  1. Completeness: Generate full code, no placeholders. If unable, explain in comments.
  2. Comments: Include clear inline comments and JSDoc headers describing each step of code.
  3. Error Checking: Implement error checking and type validation.
  4. Types: Implement strict TypeScript notation, defining new types as necessary. Additionally:
    • Do not use the 'any' type.
    • Do not use the non-null assertion operator (!).
    • Do not cast to unknown (e.g. as unknown as T).
  5. Strings: Adhere to these standards for strings:
    • Use single quotes (') for strings.
    • Use string templates instead of operational concatenation.

It is critically important that you adhere to the above five rules.

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 · 18 lines · 255 tokens per session scan A 24b4bd1b10bf

Subscribe to this mod's changes

cursorrules is a cursor rule published in the GitHub repository SmythOS/smythos-studio (295 stars, last pushed 5mo ago), licensed MIT. It adds 255 tokens to every session, about $0.0013 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.