zod4
Zod 4 Expert Guide
Zod 4 is a major release with significant performance improvements, reduced TypeScript compilation times, and a cleaner API. This skill covers migration from v3 and idiomatic Zod 4 usage.
Quick Migration Checklist
Before diving deep, address these high-impact breaking changes:
| Change | Zod 3 | Zod 4 |
|---|---|---|
| Record schemas | z.record(z.string()) |
z.record(z.string(), z.string()) |
| Strict objects | .strict() |
z.strictObject({...}) |
| Passthrough | .passthrough() |
z.looseObject({...}) |
| Error formatting | err.format() |
z.treeifyError(err) |
| Coerce input type | string |
unknown |
More from kastalien-research/thoughtbox-dot-claude
effect-ts
Comprehensive guide for Effect-TS, the functional TypeScript library. Use when building Effect applications, especially MCP servers. Covers correct APIs, common misconceptions, and MCP-specific patterns.
287docker patterns
Multi-stage builds, security, optimization
19mcp-client-builder
Build production-ready MCP clients in TypeScript or Python. Handles connection lifecycle, transport abstraction, tool orchestration, security, and error handling. Use for integrating LLM applications with MCP servers.
17skill-creator
Guide for creating effective skills. This skill should be used when users want to create a new skill (or update an existing skill) that extends Claude's capabilities with specialized knowledge, workflows, or tool integrations.
13mcp-builder
Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK).
11template-skill
Replace with description of the skill and when Claude should use it.
11