# Interface: `IKernels`

[@jupyterlite/kernel](../modules/jupyterlite_kernel.md).IKernels

An interface for the Kernels service.


## Properties

### `list`

>
> **`list`**: () => `Promise`<`IModel`[]\>

#### Type declaration

>
> (): `Promise`<`IModel`[]\>

List the running kernels.

##### Returns

`Promise`<`IModel`[]\>

#### Defined in

[packages/kernel/src/tokens.ts:47](https://github.com/jupyterlite/jupyterlite/blob/c78cc8d/packages/kernel/src/tokens.ts#L47)



### `restart`

>
> **`restart`**: (`id`: `string`) => `Promise`<`IModel`\>

#### Type declaration

>
> (`id`): `Promise`<`IModel`\>

Restart a kernel.

##### Parameters

| Name | Type | Description |
| :------ | :------ | :------ |
| `id` | `string` | The kernel id. |

##### Returns

`Promise`<`IModel`\>

#### Defined in

[packages/kernel/src/tokens.ts:42](https://github.com/jupyterlite/jupyterlite/blob/c78cc8d/packages/kernel/src/tokens.ts#L42)



### `shutdown`

>
> **`shutdown`**: (`id`: `string`) => `Promise`<`void`\>

#### Type declaration

>
> (`id`): `Promise`<`void`\>

Shut down a kernel.

##### Parameters

| Name | Type | Description |
| :------ | :------ | :------ |
| `id` | `string` | The kernel id. |

##### Returns

`Promise`<`void`\>

#### Defined in

[packages/kernel/src/tokens.ts:54](https://github.com/jupyterlite/jupyterlite/blob/c78cc8d/packages/kernel/src/tokens.ts#L54)



### `startNew`

>
> **`startNew`**: (`options`: [`IKernelOptions`](jupyterlite_kernel.Kernels.IKernelOptions.md)) => `Promise`<`IModel`\>

#### Type declaration

>
> (`options`): `Promise`<`IModel`\>

Start a new kernel.

##### Parameters

| Name | Type | Description |
| :------ | :------ | :------ |
| `options` | [`IKernelOptions`](jupyterlite_kernel.Kernels.IKernelOptions.md) | The kernel startup options. |

##### Returns

`Promise`<`IModel`\>

#### Defined in

[packages/kernel/src/tokens.ts:35](https://github.com/jupyterlite/jupyterlite/blob/c78cc8d/packages/kernel/src/tokens.ts#L35)

## Methods

### `get`

>
> **`get`**(`id`): `Promise`<`undefined` \| [`IKernel`](jupyterlite_kernel.IKernel-1.md)\>

Get a kernel by id

#### Parameters

| Name | Type | Description |
| :------ | :------ | :------ |
| `id` | `string` | The kernel id. |

#### Returns

`Promise`<`undefined` \| [`IKernel`](jupyterlite_kernel.IKernel-1.md)\>

the kernel if it exists, undefined otherwise.

#### Defined in

[packages/kernel/src/tokens.ts:62](https://github.com/jupyterlite/jupyterlite/blob/c78cc8d/packages/kernel/src/tokens.ts#L62)