typescript-standards

A set of rules for writing safer, clearer TypeScript, a version of JavaScript that supports types. It covers strict configuration, explicit types, error handling, and typed APIs.

In plain words
What is it for?
Use it when configuring tsconfig.json, defining functions and data structures, handling errors, narrowing types, and importing or exporting type definitions.
Why use it?
It reduces mistakes caused by unclear or missing types and keeps TypeScript settings and code consistent.

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/usrrname/cursorrules/typescript-standards-auto
Clone the repo
git clone --depth 1 https://github.com/usrrname/cursorrules

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 984 The whole file, excluding the scripts and references it only reads on demand.
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 $0.00000 $0.00984
Opus 5 $0.00000 $0.00492
Sonnet 5 $0.00000 $0.00197
Haiku 4.5 $0.00000 $0.00098

Measured yesterday against content hash a3ca8a2c600c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

typescript-standards 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.

.cursor/rules/standards/typescript-standards-auto.mdc · 119 lines

How it starts

The opening of the file, as written. The whole thing — 119 lines — stays where its author put it; the contents beside it link to each section on GitHub.

TypeScript Standards

Critical Rules

  • Refer to https://www.typescriptlang.org/tsconfig when tsconfig.json values are changed.
  • Use strict mode with "strict": true in tsconfig.json
  • Remind user the limitations of using esModuleInterop and allowSyntheticDefaultImports in tsconfig.json https://www.typescriptlang.org/tsconfig/#Interop_Constraints_6252
  • Explicitly declare types for function parameters and return values
  • Avoid using any type unless absolutely necessary. Use unknown instead.
  • Use interfaces for object type definitions
  • Use enums for fixed sets of values
  • Use type aliases to simplify complex types
  • Document APIs with JSDoc comments
  • Maintain proper error handling with typed errors
  • Use type guards and type narrowing to improve type safety
  • Use type literals and unions to define the exact allowed values.
  • Use type assertions and annotations when necessary. They are unnecessary if type inference is possible.
  • Use type unions and intersections to combine types.
  • Export types from modules using the export type syntax
  • If using an existing library with types, import the types using the import type syntax
  • Declare types for file extensions that aren't supported by the compiler using the declare module syntax
  • If using node 23+, use node --experimental-strip-types in package.json scripts to strip types when running the code locally
  • Use utility types as much as possible to avoid type duplication.

Read the full file on GitHub · 119 lines

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. yesterday First seen · 119 lines · 984 tokens per session scan A a3ca8a2c600c

Subscribe to this mod's changes

typescript-standards is a cursor rule published in the GitHub repository usrrname/cursorrules (10 stars, last pushed 4mo ago), licensed ISC. It costs nothing until one of its globs matches a file; then it loads 984 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.