> For the complete documentation index, see [llms.txt](https://docs.watchdata.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.watchdata.io/blockchain-apis/tron-api/tronz-shielded-smart-contract/createspendauthsig.md).

# CreateSpendAuthSig

**Body params**: 

* `ask`
* `tx_hash`
* `alpha`

**Request**

```
curl --request POST \
     --url https://tron.api.watchdata.io/wallet/createspendauthsig \
     --header 'Accept: application/json' \
     --header 'Content-Type: application/json' \
     --data '
{
     "ask": "string",
     "tx_hash": "string",
     "alpha": "string"
}
'
```

**Response**

```
{
  "Error": "class org.tron.core.services.http.JsonFormat$ParseException : 1:8: INVALID hex String"
}
```