Terminal.skills
Skills/yup
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yup

Validate data with Yup schemas. Use when adding form validation, defining API request schemas, validating configuration, or building type-safe validation pipelines in JavaScript/TypeScript.

#yup#validation#schema#forms#typescript
terminal-skillsv1.0.0
Works with:claude-codeopenai-codexgemini-clicursor
Source

Usage

$
✓ Installed yup v1.0.0

Getting Started

  1. Install the skill using the command above
  2. Open your AI coding agent (Claude Code, Codex, Gemini CLI, or Cursor)
  3. Reference the skill in your prompt
  4. The AI will use the skill's capabilities automatically

Example Prompts

  • "Review the open pull requests and summarize what needs attention"
  • "Generate a changelog from the last 20 commits on the main branch"

Documentation

Overview

Yup is a schema validation library for JavaScript. Define schemas declaratively, validate data, and get detailed error messages. Works with Formik, react-hook-form, and standalone. TypeScript-first with type inference.

Instructions

Step 1: Schemas

typescript
import * as yup from 'yup'

const userSchema = yup.object({
  name: yup.string().min(2).max(100).required(),
  email: yup.string().email().required(),
  age: yup.number().positive().integer().min(13).max(120),
  role: yup.string().oneOf(['admin', 'member', 'viewer']).default('member'),
  tags: yup.array().of(yup.string()).min(1).max(10),
  address: yup.object({
    street: yup.string().required(),
    city: yup.string().required(),
    zip: yup.string().matches(/^\d{5}$/, 'Must be 5 digits'),
  }),
})

// Validate
const user = await userSchema.validate(data, { abortEarly: false })

// Type inference
type User = yup.InferType<typeof userSchema>

Step 2: Custom Validation

typescript
const passwordSchema = yup.string()
  .min(8)
  .matches(/[A-Z]/, 'Must contain uppercase')
  .matches(/[0-9]/, 'Must contain number')
  .matches(/[^A-Za-z0-9]/, 'Must contain special character')

const signupSchema = yup.object({
  password: passwordSchema.required(),
  confirmPassword: yup.string()
    .oneOf([yup.ref('password')], 'Passwords must match')
    .required(),
})

Step 3: Conditional Validation

typescript
const schema = yup.object({
  contactMethod: yup.string().oneOf(['email', 'phone']).required(),
  email: yup.string().when('contactMethod', {
    is: 'email',
    then: (s) => s.email().required('Email required when contact method is email'),
  }),
  phone: yup.string().when('contactMethod', {
    is: 'phone',
    then: (s) => s.matches(/^\+\d{10,15}$/).required('Phone required'),
  }),
})

Guidelines

  • abortEarly: false returns all errors at once — better UX than one-at-a-time.
  • Use InferType to derive TypeScript types from schemas — single source of truth.
  • For new projects, consider Zod instead — better TypeScript inference and ecosystem.
  • Yup is still the standard for Formik integration.
  • .when() for conditional validation — fields required only in certain contexts.

Information

Version
1.0.0
Author
terminal-skills
Category
Development
License
Apache-2.0