# Typescript

> TypeScript strict typing for app and library code. Use when writing or reviewing TypeScript, fixing type errors, or when the project uses tsconfig strict. Prefer typed APIs over any.

- Skill: `vostrikovva/typescript` (Agent Skill)
- Install (CLI): `npx skillmds@latest add vostrikovva/typescript`
- Raw SKILL.md: https://api.skillmd.com/api/skills/vostrikovva/typescript/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: vostrikovva (https://skillmd.com/u/vostrikovva)
- Updated: 2026-09-21
- Page: https://skillmd.com/skills/vostrikovva/typescript

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# TypeScript

Default for this catalog: **TypeScript `strict`**, not JavaScript. Prefer typed APIs over `any`. `tsconfig` location and `paths` come from recon, not assumed repo root.

## Rules

- Enable `strict` in `tsconfig.json`. Do not weaken it for convenience.
- Do not use `any` unless the user accepts an escape hatch at a typed boundary (third-party untyped module). Prefer `unknown` and narrow.
- Type public APIs: function params/returns, React props, Express/Nest handlers, IPC commands, DB row types.
- Prefer `type` or `interface` consistently with the file you are editing.
- Do not use `as` to silence errors. Narrow or fix the source type.
- Generated examples in `.ts` / `.tsx` only.

## Boundaries

Serialize at process edges (HTTP, IPC, env). Validate input (schema or Nest pipes) then keep a typed value inward. Never print secrets from `process.env` into chat.