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Zod Schema Management

Development
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Create and modify Zod schemas for runtime validation with proper type inference.

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I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/majiayu000/claude-skill-registry/blob/HEAD/skills/development/zod-carrot-foundation-methodology-rules-2/SKILL.md

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First, summarize what it does, its dependencies, license status if identifiable, and any risks. Show the exact files you propose to add under .agents/skills/zod-schema-management/. Do not write files or run scripts until I approve.

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

  1. Define schemas with specificity: Prefer concrete schema methods over loose ones.

    • Use z.string().min(1) instead of bare z.string() for required non-empty strings
    • Use z.number().int().nonnegative() instead of bare z.number() when appropriate
    • Use z.enum() for known string unions
    • Use z.literal() for exact values

  2. Derive types from schemas: Always use z.infer<typeof Schema> to derive TypeScript types from Zod schemas. Do not define the type separately and the schema separately — the schema is the source of truth.

    const MySchema = z.object({
  name: z.string().min(1),
  count: z.number().int().nonnegative(),
});
type My = z.infer<typeof MySchema>;

  3. Choose the right parse method:

    • .safeParse() for external or untrusted input (API payloads, user input, parsed documents) — check .success before using .data
    • .parse() for internal guaranteed data where a thrown error indicates a programming bug

  4. Colocate schema with type: Place the Zod schema in the same file as the type it defines. Export both the schema and the inferred type.

  5. Test stubs: Use zocker with createStubFromSchema() from @carrot-fndn/shared/testing to generate test data from schemas. This ensures stubs always match the schema definition.

  6. Schema composition: Use .extend(), .merge(), .pick(), .omit(), and .partial() to compose schemas from existing ones rather than duplicating field definitions.

  7. Optional fields: Use z.optional() or .optional() for truly optional fields. Remember that exactOptionalPropertyTypes is enabled in tsconfig, so optional fields must be explicitly marked.