---
meta:
  title:
    "At least one of the custom notification kinds you provided for
    'ActivitiesData' does not match its requirements"
  parentTitle: "Error"
  description: "Your 'ActivitiesData' type is incorrect and needs to be updated"
---

## Why this error occurred

You have provided a custom `ActivitiesData` type for your application, but the
type you provided isn’t a (completely) valid definition.

```ts highlight="4-8"
declare global {
  interface Liveblocks {
    ActivitiesData: {
      // Your custom notification kinds go here...
      $error: {
        code: number;
        date: Date; // ❌ Values must simple
      };
      // ❌ Custom notification kinds must start with $
      success: {
        message: string;
      };
    };
  }
}
```

In the example above, there are two problems. Activities data may only contain
simple key/value pairs, where the values must always be assignable to
`string | number | boolean | undefined` and custom notification kinds must start
with `$`.

## How to fix it

You’ll need to figure out what part of your provided `ActivitiesData` type
definition isn’t valid. The example above could be fixed as such:

```ts highlight="6-8"
declare global {
  interface Liveblocks {
    ActivitiesData: {
      // Your custom notification kinds go here...
      $error: {
        code: number;
        date: string;
      };
      $success: {
        message: string;
      };
    };
  }
}
```

## If you cannot find the root cause

Sometimes types can be complex and the root cause is still unclear. In those
cases, there is a small trick you can use. Try to assign your type to the
required base type, with this line:

```ts highlight="9-10"
import type { BaseActivitiesData } from "@liveblocks/client";

declare global {
  interface Liveblocks {
    ActivitiesData: MyActivitiesData;
  }
}

// Quick debugging snippet to find root cause
const xxx: BaseActivitiesData = {} as MyActivitiesData;
//    ^?
//    The error will appear here
```

Now TypeScript will explain why it thinks your type isn’t valid:

```error showLineNumbers={false}
Type 'MyActivitiesData' is not assignable to type 'BaseActivitiesData'.
  Property 'date' is incompatible with index signature.
    Type 'Date' is not assignable to type 'string | number | boolean | undefined'.
```

---

For an overview of all available documentation, see [/llms.txt](/llms.txt).