# Chai

> Chai BDD/TDD assertion library reference for JavaScript testing. Covers expect/should/assert styles, deep equality, type checks, string/array/object matchers, error assertions, chai-as-promised, chai-http for API testing, sinon-chai, and custom assertions.

- Skill: `bytesagain/chai` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add bytesagain/chai`
- Raw SKILL.md: https://api.skillmd.com/api/skills/bytesagain/chai/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Integrations & APIs
- Author: bytesagain (https://skillmd.com/u/bytesagain)
- Updated: 2026-08-19
- Page: https://skillmd.com/skills/bytesagain/chai

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# Chai Reference

BDD/TDD assertion library for JavaScript.

## Commands

| Command | Description |
|---------|-------------|
| `intro` | Overview, styles, plugins |
| `expect` | Expect API, matchers |
| `advanced` | Errors, promises, HTTP, custom |