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+---
+description: Get expert guidance on XState v5 state machines and actor model implementation
+argument-hint: '[what-you-need]'
+---
+
+# XState v5 Expert Guidance
+
+Provide expert guidance on implementing XState v5 state machines, actors, and statecharts with TypeScript best practices for backend applications.
+
+## Usage
+
+```bash
+/xstate [optional: what you need help with]
+```
+
+**Arguments:**
+
+- `what-you-need` (optional): Describe what you're trying to implement or paste code you need help with
+
+## Instructions
+
+When this command is invoked:
+
+1. **Load the xstate-v5 skill** from `skills/xstate-v5/SKILL.md`
+
+2. **If the user provided context**, analyze their needs and:
+   - Identify which XState patterns or APIs apply to their situation
+   - Provide specific code examples using XState v5 APIs
+   - Show TypeScript integration when relevant
+   - Explain best practices and common pitfalls
+   - Reference the appropriate documentation from `references/`:
+     - Core API Reference for function documentation
+     - Actors Reference for actor model guidance
+     - Common Patterns for production-ready examples
+     - TypeScript Integration for typing help
+     - Testing Strategies for test guidance
+
+3. **If no context was provided**, offer to help by:
+   - Asking what they're trying to implement or what problem they're solving
+   - Listing common scenarios:
+     - Creating state machines with `createMachine` and `setup`
+     - Managing actor lifecycle and communication
+     - Implementing loading states, authentication flows, or wizards
+     - Adding TypeScript types to machines
+     - Testing with xstate-audition
+     - Performance optimization
+   - Offering to show examples of specific patterns
+
+4. **Always emphasize XState v5 best practices**:
+   - Always use `setup()` for better type inference and reusable logic
+   - Name all actions and guards (avoid inline functions)
+   - Use context for data, states for behavior
+   - Keep machines focused - one machine per logical unit
+   - Leverage TypeScript for compile-time safety
+   - Don't mutate context directly - always use `assign`
+   - Don't use side effects in guards - guards should be pure
+   - Use Promise actors for asynchronous operations
+
+5. **Focus on backend use cases**:
+   - This plugin is tailored for Node.js/Deno/Bun backend applications
+   - Emphasize server-side patterns: database transactions, API orchestration, rate limiting
+   - Reference backend-specific patterns from the Common Patterns reference
+
+## Example Interactions
+
+**With context - creating a machine:**
+
+```text
+User: /xstate I need to implement a loading state pattern with retry logic
+
+Agent: Here's an XState v5 loading pattern with retry logic:
+
+\`\`\`typescript
+import { setup, assign, fromPromise } from 'xstate';
+
+const fetchMachine = setup({
+  types: {
+    context: {} as {
+      data: string | null;
+      error: Error | null;
+      retryCount: number;
+    },
+    events: {} as
+      | { type: 'FETCH' }
+      | { type: 'RETRY' }
+      | { type: 'RESET' },
+  },
+  actors: {
+    fetchData: fromPromise<string, void>(async () => {
+      const response = await fetch('https://api.example.com/data');
+      return response.text();
+    }),
+  },
+  actions: {
+    assignData: assign({
+      data: ({ event }) => (event as any).output,
+      error: null,
+    }),
+    assignError: assign({
+      error: ({ event }) => (event as any).error,
+    }),
+    incrementRetry: assign({
+      retryCount: ({ context }) => context.retryCount + 1,
+    }),
+    resetRetry: assign({
+      retryCount: 0,
+    }),
+  },
+  guards: {
+    canRetry: ({ context }) => context.retryCount < 3,
+  },
+}).createMachine({
+  id: 'fetch',
+  initial: 'idle',
+  context: {
+    data: null,
+    error: null,
+    retryCount: 0,
+  },
+  states: {
+    idle: {
+      on: {
+        FETCH: 'loading',
+      },
+    },
+    loading: {
+      invoke: {
+        src: 'fetchData',
+        onDone: {
+          target: 'success',
+          actions: ['assignData', 'resetRetry'],
+        },
+        onError: {
+          target: 'failure',
+          actions: 'assignError',
+        },
+      },
+    },
+    success: {
+      on: {
+        RESET: 'idle',
+      },
+    },
+    failure: {
+      on: {
+        RETRY: {
+          target: 'loading',
+          guard: 'canRetry',
+          actions: 'incrementRetry',
+        },
+        RESET: 'idle',
+      },
+    },
+  },
+});
+\`\`\`
+
+Key XState v5 patterns used:
+- `setup()` for type-safe configuration and reusable logic
+- Named actions and guards for clarity
+- Promise actors with `fromPromise` for async operations
+- Context for data management (data, error, retryCount)
+- Guards for conditional transitions (retry limit)
+- `assign` for immutable context updates
+
+This pattern is common for backend API calls. See [references/patterns.md] for more examples.
+```
+
+**With context - TypeScript help:**
+
+```text
+User: /xstate How do I add strong typing to my machine?
+
+Agent: Use the `setup()` pattern for strong typing in XState v5:
+
+\`\`\`typescript
+import { setup, assign } from 'xstate';
+
+// Define your types
+interface UserContext {
+  userId: string | null;
+  userData: User | null;
+  error: Error | null;
+}
+
+type UserEvents =
+  | { type: 'LOGIN'; userId: string }
+  | { type: 'LOGOUT' }
+  | { type: 'FETCH_USER' };
+
+// Use setup for type inference
+const userMachine = setup({
+  types: {
+    context: {} as UserContext,
+    events: {} as UserEvents,
+  },
+  actions: {
+    setUserId: assign({
+      userId: ({ event }) => {
+        // TypeScript knows event can be LOGIN
+        if (event.type === 'LOGIN') {
+          return event.userId;
+        }
+        return null;
+      },
+    }),
+    clearUser: assign({
+      userId: null,
+      userData: null,
+    }),
+  },
+}).createMachine({
+  id: 'user',
+  initial: 'loggedOut',
+  context: {
+    userId: null,
+    userData: null,
+    error: null,
+  },
+  states: {
+    loggedOut: {
+      on: {
+        LOGIN: {
+          target: 'loggedIn',
+          actions: 'setUserId',
+        },
+      },
+    },
+    loggedIn: {
+      on: {
+        LOGOUT: {
+          target: 'loggedOut',
+          actions: 'clearUser',
+        },
+      },
+    },
+  },
+});
+\`\`\`
+
+Key TypeScript patterns:
+- Define context and event types explicitly
+- Use `{} as Type` syntax in `types` config
+- TypeScript infers types throughout the machine
+- Event types are narrowed in action implementations
+- No `any` types needed
+
+See [references/typescript.md] for advanced patterns including generic machine factories.
+```
+
+**With context - debugging:**
+
+```text
+User: /xstate Why is my context not updating?
+const machine = createMachine({
+  context: { count: 0 },
+  on: {
+    INC: { actions: (ctx) => ctx.context.count++ }
+  }
+});
+
+Agent: The issue is that you're mutating context directly, which XState doesn't detect. Always use `assign` for context updates:
+
+\`\`\`typescript
+// ❌ WRONG - mutating context directly
+on: {
+  INC: { actions: (ctx) => ctx.context.count++ }
+}
+
+// ✅ CORRECT - use assign for immutable updates
+import { assign } from 'xstate';
+
+on: {
+  INC: {
+    actions: assign({
+      count: ({ context }) => context.count + 1
+    })
+  }
+}
+\`\`\`
+
+This is a common mistake! XState requires immutable context updates to:
+1. Maintain predictable state transitions
+2. Enable time-travel debugging
+3. Support snapshot serialization
+4. Ensure proper actor communication
+
+Other common mistakes to avoid:
+- Don't use side effects in guards (guards should be pure)
+- Don't overuse nested states (flatten when possible)
+- Don't use `setInterval` in machines (use delays instead)
+
+Want to see more best practices?
+```
+
+**Without context:**
+
+```text
+User: /xstate
+
+Agent: I can help you with XState v5! What are you trying to implement?
+
+Common use cases:
+- **State machines** - Model application logic with explicit states and transitions
+- **Actor systems** - Manage concurrent actors and communication
+- **Loading patterns** - Implement fetch/retry/timeout logic
+- **Authentication flows** - Handle login/logout/session management
+- **Wizards & forms** - Multi-step forms with validation
+- **Backend workflows** - Database transactions, message queue processing, rate limiting
+- **TypeScript integration** - Add strong typing to your machines
+- **Testing** - Test actors with xstate-audition
+
+You can also:
+- Paste your existing state machine code for review
+- Ask about specific XState v5 APIs
+- Request examples of common patterns
+- Get help debugging issues
+
+I have access to comprehensive documentation:
+- Core API reference (setup, createMachine, actors, actions, guards)
+- Actor model guide (all actor types, spawning, communication)
+- Common patterns (loading, auth, forms, pagination, etc.)
+- TypeScript integration patterns
+- Testing strategies with xstate-audition
+
+What would you like to work on?
+```
+
+## Related Files
+
+- [XState v5 Skill](../skills/xstate-v5/SKILL.md)
+- [Core API Reference](../skills/xstate-v5/references/core-api.md)
+- [Actors Reference](../skills/xstate-v5/references/actors.md)
+- [Common Patterns](../skills/xstate-v5/references/patterns.md)
+- [TypeScript Integration](../skills/xstate-v5/references/typescript.md)
+- [Testing Strategies](../skills/xstate-v5/references/testing.md)