# TS Patterns

> TypeScript patterns and idioms reference. Use when writing TypeScript and need a quick refresher on generics, discriminated unions, builder patterns, or error handling.

- Skill: `contentful/ts-patterns` (Agent Skill, multi-file: 4 files)
- Install (CLI): `npx skillmds@latest add contentful/ts-patterns`
- Raw SKILL.md: https://api.skillmd.com/api/skills/contentful/ts-patterns/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: contentful (https://skillmd.com/u/contentful)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/contentful/ts-patterns

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# ts-patterns

This skill provides reference information on demand.

## MCP mode (preferred)

If you have MCP tools for this skill (e.g., `mcp__ts-patterns__topic`), use them:

- Call `topics` to list available reference topics.
- Call `topic` with a topic name to retrieve its content.

Present the content to the user. Do not show raw tool calls.

## CLI mode (fallback)

Resolve the **absolute path** to `scripts/run`
from this SKILL.md file's directory. Use the absolute path in all commands — do not `cd` into the
skill directory. In the examples below, `<skill>/scripts/run` is a placeholder for this absolute path.

- `<skill>/scripts/run topic generics` — Generics cheat sheet — constraints, conditional types, mapped types, infer
- `<skill>/scripts/run topic discriminated-unions` — Discriminated unions — type narrowing with literal discriminants
- `<skill>/scripts/run topic builder-pattern` — Builder pattern — fluent APIs with type accumulation
- `<skill>/scripts/run topic error-handling` — Error handling — Result types, custom errors, exhaustive matching

To list all available topics: `<skill>/scripts/run`