Agent skill

state-management

TanStack Query + Zustand patterns.

View SKILL.md on GitHub Repository
Stars 232
Forks 15

Install this agent skill to your Project

npx add-skill https://github.com/aiskillstore/marketplace/tree/main/skills/barnhardt-enterprises-inc/state-management

SKILL.md

State Management

Philosophy

  • Server State → TanStack Query
  • Client State → Zustand
  • Form State → React Hook Form + Zod
  • URL State → nuqs or searchParams

TanStack Query

Query Keys Factory

typescript
export const userKeys = {
  all: ['users'] as const,
  lists: () => [...userKeys.all, 'list'] as const,
  list: (filters: Filters) => [...userKeys.lists(), filters] as const,
  details: () => [...userKeys.all, 'detail'] as const,
  detail: (id: string) => [...userKeys.details(), id] as const,
};

Hooks Pattern

typescript
export function useUsers(filters?: Filters) {
  return useQuery({
    queryKey: userKeys.list(filters ?? {}),
    queryFn: () => getUsers(filters),
  });
}

export function useUser(id: string) {
  return useQuery({
    queryKey: userKeys.detail(id),
    queryFn: () => getUser(id),
    enabled: !!id,
  });
}

export function useCreateUser() {
  const queryClient = useQueryClient();
  return useMutation({
    mutationFn: createUser,
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: userKeys.lists() });
    },
  });
}

export function useUpdateUser() {
  const queryClient = useQueryClient();
  return useMutation({
    mutationFn: ({ id, data }: { id: string; data: UpdateUserInput }) =>
      updateUser(id, data),
    onSuccess: (_, { id }) => {
      queryClient.invalidateQueries({ queryKey: userKeys.detail(id) });
      queryClient.invalidateQueries({ queryKey: userKeys.lists() });
    },
  });
}

Zustand

Typed Store

typescript
interface UIStore {
  sidebarOpen: boolean;
  theme: 'light' | 'dark';
  toggleSidebar: () => void;
  setTheme: (theme: 'light' | 'dark') => void;
}

export const useUIStore = create<UIStore>((set) => ({
  sidebarOpen: true,
  theme: 'light',
  toggleSidebar: () => set((s) => ({ sidebarOpen: !s.sidebarOpen })),
  setTheme: (theme) => set({ theme }),
}));

Performance: Use Selectors

typescript
// CORRECT - Only re-renders when sidebarOpen changes
const sidebarOpen = useUIStore((s) => s.sidebarOpen);

// WRONG - Re-renders on ANY state change
const { sidebarOpen } = useUIStore();

Persist Middleware

typescript
import { persist } from 'zustand/middleware';

export const useSettingsStore = create<SettingsStore>()(
  persist(
    (set) => ({
      language: 'en',
      setLanguage: (language) => set({ language }),
    }),
    {
      name: 'settings-storage',
    }
  )
);

Computed Values with Selectors

typescript
// Create a selector
const selectFilteredItems = (state: Store) =>
  state.items.filter(item => item.active);

// Use in component
const filteredItems = useStore(selectFilteredItems);

Form State: React Hook Form + Zod

typescript
import { useForm } from 'react-hook-form';
import { zodResolver } from '@hookform/resolvers/zod';
import { z } from 'zod';

const schema = z.object({
  name: z.string().min(1, 'Required'),
  email: z.string().email('Invalid email'),
});

type FormData = z.infer<typeof schema>;

export function UserForm() {
  const { register, handleSubmit, formState: { errors } } = useForm<FormData>({
    resolver: zodResolver(schema),
  });

  const onSubmit = (data: FormData) => {
    // data is typed and validated
  };

  return (
    <form onSubmit={handleSubmit(onSubmit)}>
      <input {...register('name')} />
      {errors.name && <span>{errors.name.message}</span>}

      <input {...register('email')} />
      {errors.email && <span>{errors.email.message}</span>}

      <button type="submit">Submit</button>
    </form>
  );
}

Recommended Agent Skills

Expand your agent's capabilities with these related and highly-rated skills.

aiskillstore/marketplace

perigon-backend

Perigon ASP.NET Core + EF Core + Aspire conventions

232 15
Explore
aiskillstore/marketplace

perigon-agent

Pointers for Copilot/agents to apply Perigon conventions

232 15
Explore
aiskillstore/marketplace

perigon-angular

Angular 21+ standalone/Material/signal conventions for Perigon WebApp

232 15
Explore
aiskillstore/marketplace

fastapi-mastery

Comprehensive FastAPI development skill covering REST API creation, routing, request/response handling, validation, authentication, database integration, middleware, and deployment. Use when working with FastAPI projects, building APIs, implementing CRUD operations, setting up authentication/authorization, integrating databases (SQL/NoSQL), adding middleware, handling WebSockets, or deploying FastAPI applications. Triggered by requests involving .py files with FastAPI code, API endpoint creation, Pydantic models, or FastAPI-specific features.

232 15
Explore
aiskillstore/marketplace

context7-efficient

Token-efficient library documentation fetcher using Context7 MCP with 86.8% token savings through intelligent shell pipeline filtering. Fetches code examples, API references, and best practices for JavaScript, Python, Go, Rust, and other libraries. Use when users ask about library documentation, need code examples, want API usage patterns, are learning a new framework, need syntax reference, or troubleshooting with library-specific information. Triggers include questions like "Show me React hooks", "How do I use Prisma", "What's the Next.js routing syntax", or any request for library/framework documentation.

232 15
Explore
aiskillstore/marketplace

browser-use

Browser automation using Playwright MCP. Navigate websites, fill forms, click elements, take screenshots, and extract data. Use when tasks require web browsing, form submission, web scraping, UI testing, or any browser interaction.

232 15
Explore

Didn't find tool you were looking for?

Be as detailed as possible for better results