# Zod Schema Generator > Generate Zod validation schemas from Prisma models, TypeScript interfaces, or JSON examples. Use when asked to generate Zod schemas, create validation, bridge Prisma to Zod, validate API input/output, or generate runtime type checks. Use when this capability is needed. - Skill: `tomevault-io/zod-schema-generator` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/zod-schema-generator` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/zod-schema-generator/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Integrations & APIs - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/zod-schema-generator --- # Zod Schema Generator Before generating any output, read `config/defaults.md` and adapt all patterns, imports, and code examples to the user's configured stack. ## Process 1. Identify the source: Prisma model, TypeScript interface/type, or raw JSON example. 2. Determine schema purpose: input validation (create/update), output validation (API response), or full round-trip. 3. Generate Zod schema with correct types, optional fields, and refinements. 4. Add `.transform()` and `.refine()` where appropriate. 5. Output the schema file with proper imports and exports. ## Source: Prisma Model Parse the Prisma model and generate both input and output schemas. ### Input Schema (for create/update) Omit auto-generated fields (`id`, `createdAt`, `updatedAt`) and fields with `@default`. ```prisma model User { id String @id @default(cuid()) email String @unique name String? role Role @default(USER) posts Post[] createdAt DateTime @default(now()) updatedAt DateTime @updatedAt } ``` ```typescript // Generated: user.schema.ts import { z } from "zod"; export const createUserSchema = z.object({ email: z.string().email().trim().toLowerCase(), name: z.string().min(1).trim().optional(), role: z.enum(["USER", "ADMIN"]).optional(), // has @default }); export const updateUserSchema = createUserSchema.partial(); export type CreateUserInput = z.infer; export type UpdateUserInput = z.infer; ``` ### Output Schema (for API responses) Include all fields. Use `z.coerce.date()` for DateTime fields. ```typescript export const userSchema = z.object({ id: z.string().cuid(), email: z.string().email(), name: z.string().nullable(), role: z.enum(["USER", "ADMIN"]), createdAt: z.coerce.date(), updatedAt: z.coerce.date(), }); export type User = z.infer; ``` ### Relations For input schemas, generate nested create/connect patterns: ```typescript // One-to-many: creating a post with author export const createPostSchema = z.object({ title: z.string().min(1).max(255), content: z.string(), author: z.union([ z.object({ connect: z.object({ id: z.string() }) }), z.object({ create: createUserSchema }), ]), }); ``` For output schemas, include the related object shape: ```typescript export const postWithAuthorSchema = postSchema.extend({ author: userSchema, }); ``` ## Source: TypeScript Interface Map TypeScript types directly to Zod equivalents. ```typescript // Input interface OrderItem { productId: string; quantity: number; price: number; notes?: string; metadata: Record; } ``` ```typescript // Generated export const orderItemSchema = z.object({ productId: z.string().uuid(), quantity: z.number().int().positive(), price: z.number().nonnegative(), notes: z.string().optional(), metadata: z.record(z.string(), z.unknown()), }); ``` ### Discriminated Unions ```typescript // Input type PaymentMethod = | { type: "card"; cardNumber: string; expiry: string } | { type: "bank"; accountNumber: string; routingNumber: string } | { type: "crypto"; walletAddress: string }; ``` ```typescript // Generated export const paymentMethodSchema = z.discriminatedUnion("type", [ z.object({ type: z.literal("card"), cardNumber: z.string().regex(/^\d{16}$/), expiry: z.string().regex(/^\d{2}\/\d{2}$/), }), z.object({ type: z.literal("bank"), accountNumber: z.string(), routingNumber: z.string().regex(/^\d{9}$/), }), z.object({ type: z.literal("crypto"), walletAddress: z.string().min(26).max(62), }), ]); ``` ## Source: JSON Example Infer schema from a JSON payload by analyzing value types and structure. ```json { "name": "Acme Corp", "employees": 150, "active": true, "tags": ["tech", "startup"], "address": { "street": "123 Main St", "city": "Springfield", "zip": "62701" } } ``` ```typescript // Generated (with refinement suggestions in comments) export const companySchema = z.object({ name: z.string().min(1), employees: z.number().int().nonnegative(), active: z.boolean(), tags: z.array(z.string()), address: z.object({ street: z.string(), city: z.string(), zip: z.string().regex(/^\d{5}(-\d{4})?$/), // inferred US zip }), }); ``` ## Common Refinements Apply these automatically when field names or patterns suggest them: | Field pattern | Refinement | |---|---| | `email` | `.email().trim().toLowerCase()` | | `url`, `website` | `.url()` | | `id`, `*Id` (cuid) | `.cuid()` or `.cuid2()` | | `uuid`, `*Uuid` | `.uuid()` | | `phone` | `.regex(/^\+?[\d\s-()]+$/)` | | `password` | `.min(8)` | | `*At` (timestamps) | `z.coerce.date()` | | `slug` | `.regex(/^[a-z0-9]+(?:-[a-z0-9]+)*$/)` | | `price`, `amount` | `.nonnegative()` | | `quantity`, `count` | `.int().nonnegative()` | ## File Placement - **Colocated**: Place schema next to the model/route it validates (e.g., `app/api/users/schema.ts`). - **Centralized**: Place in `lib/validations/` or `src/schemas/` when schemas are shared across multiple routes. Match the project's existing pattern. Default to colocated if no convention exists. ## Output Format ``` ## Generated Zod Schema **Source**: [Prisma model | TypeScript interface | JSON example] **File**: `path/to/schema.ts` [Generated code block] ### Refinements Applied - `email`: Added `.email().trim().toLowerCase()` - `createdAt`: Used `z.coerce.date()` for DateTime ### Usage Example [Short example showing schema.parse() or schema.safeParse()] ``` ## Reference See [references/prisma-zod-mapping.md](references/prisma-zod-mapping.md) for the complete Prisma-to-Zod type mapping table and refinement catalog. --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/nembie) — claim your Tome and manage your conversions.