# Function: readChallenge()

> **readChallenge**\<`T`\>(`href?`): `T` \| `undefined`

Defined in: [link.ts:37](https://github.com/debuffjp/debuff/blob/3e11cb8bf00adfd52d063977f9e3328e72e765c5/packages/share/src/link.ts#L37)

The challenge this page was opened with, or `undefined`. Malformed links read as no challenge.

## Type Parameters

### T

`T` *extends* [`ChallengeData`](../type-aliases/ChallengeData.md) = [`ChallengeData`](../type-aliases/ChallengeData.md)

## Parameters

### href?

`string` = `location.href`

## Returns

`T` \| `undefined`