10 JavaScript & TypeScript Prompts for AI Code Generation: React, Node.js & Utilities

Writing JavaScript and TypeScript by hand is no longer the only path. With AI assistants like ChatGPT, Claude, and GitHub Copilot, developers can generate React components, Node.js endpoints, and TypeScript utilities in seconds. But output quality depends almost entirely on prompt quality: a vague request like "write a button in React" returns generic code, while a well-structured prompt returns typed, production-ready code.

This guide is a copy-paste collection of prompts for JavaScript and TypeScript code generation. We cover React, Node.js, and reusable TS utilities. Every prompt follows one philosophy: give the model context, constraints, and an explicit output format so the result drops into your project with minimal edits.

Why Prompt Engineering Matters for JS/TS

AI models default to average code: untyped JavaScript, missing error handling, outdated patterns. Your prompt is the steering wheel. Strong generation prompts share four traits:

1. Context — framework, versions, project structure.
2. Constraints — strict TypeScript, no external dependencies.
3. Output format — file names, exports, comment style.
4. Acceptance criteria — edge cases the code must handle.

React Component Prompts

1. Generate a typed React component

Use this when you need a UI element that matches your design system and TypeScript conventions.

You are a senior React developer using TypeScript and Tailwind CSS. Generate a reusable Button component: props variant ('primary'

|'secondary'|'ghost'), size ('sm'|'md'|'lg'), disabled, onClick, children; use React.forwardRef to expose the native button ref; export proper TypeScript types; style with Tailwind via a mapped class object
and a loading state. Use a mapped class object for Tailwind styles and a separate variant/size type export. Return the complete component code as a single .tsx file with no extra explanation.

Why this works: the prompt names the exact props, forces forwardRef, and asks for exported types. The model knows to handle disabled and to apply classes conditionally. Without the ref and type instructions, you'd get a functional component without the native button behavior.

2. Generate a custom React hook

Use this when you need logic that manages state, effects, and return values with strict types.

You are a senior TypeScript developer. Write a React hook called useLocalStorage<T>(key: string, initialValue: T) that:
- reads the value from localStorage lazily on first render
- handles JSON.parse errors gracefully by falling back to initialValue
- updates the stored value whenever the state changes via a useEffect
- exposes a setValue function that also writes through to localStorage
- returns [value, setValue] as a const tuple, not an array
- supports SSR by checking typeof window
Include full JSDoc comments and export the hook as a named export. Return only the .ts file.

3. Generate a React form with validation

Use this when you need a controlled form with error messages and no external form library.

You are a React engineer using TypeScript and React 18. Build a login form component with email and password fields. Requirements:
- use useState for values and errors
- validate email format and minimum password length of 8
- show inline error messages below each field on blur
- disable the submit button while validating
- call an onSubmit prop typed as (values: { email: string; password: string }) => Promise<void>
- display a loading spinner on the submit button while awaiting onSubmit
Use Tailwind CSS for styling and export the component as a named export. Return only the .tsx file.

Node.js Prompt Patterns

4. Generate an Express endpoint

You are a senior Node.js developer working with Express 4 and TypeScript. Create an async route handler for POST /api/users that:
- validates name, email, and password with a simple schema you define inline
- rejects requests with a 400 response and a { errors: string[] } body
- throws a 409 error if a user with the same email already exists (simulate with a mock function)
- returns 201 with the newly created user object minus the password
- wraps the handler in an asyncWrapper utility that catches errors and forwards them to Express error middleware
Include the types for Request, Response, and NextFunction. Return only the .ts file.

5. Generate a rate-limited API route

You are a Node.js API engineer. Write a middleware factory called rateLimit(options: { windowMs: number; max: number }) using an in-memory Map. The middleware should:
- return 429 with a Retry-After header when the limit is exceeded
- clean up expired entries periodically to avoid memory leaks
- be usable as a drop-in Express middleware
- export TypeScript types for the options object
Return only the .ts file.

TypeScript Utility Prompts

6. Generate a typed deep partial

You are a TypeScript library author. Create a utility type DeepPartial<T> that recursively makes all properties optional, including nested objects and arrays. Also provide a type guard function isDeepPartial<T>(value: unknown): value is DeepPartial<T> that performs a shallow runtime check on first-level keys. Add JSDoc examples. Return only the .ts file.

7. Generate an async retry utility

You are a senior TypeScript developer. Write a function retryAsync<T>(fn: () => Promise<T>, options?: { retries?: number; delayMs?: number; backoff?: 'fixed' | 'exponential' }): Promise<T> that:
- retries fn when it rejects, up to retries times
- waits delayMs between attempts; if backoff is 'exponential', multiply delay by 2 each retry
- logs each retry with console.warn
- rethrows the last error if all attempts fail
- has complete TypeScript generics and overloads
Return only the .ts file.

Prompt Chaining for Project-Scale Generation

You can combine these prompts to generate an entire feature. Start with a utility, then the hook, then the component, then the endpoint. For example:

1. Generate types.ts with your domain models.
2. Generate a validation.ts utility that works with those types.
3. Generate a hook that uses the validation.
4. Generate a UI component that uses the hook.
5. Generate a Node endpoint that shares the same types.

Because each prompt references