# validate_auth_descriptor_args · FT4 Rell API · Chromia Docs (concept)

> function validate_ auth_ descriptor_ args(auth_ descriptor: auth_descriptor ) Checks if the auth descriptor args correspond to single_sig_args or multi_sig

Source: https://docs.chromia.com/pages/ft4-rell/-f-t4-library/lib.ft4.core.accounts/validate_auth_descriptor_args/

FUNCTION

# validate\_auth\_descriptor\_args

```signature
function validate_auth_descriptor_args(auth_descriptor: auth_descriptor)
```

[Source](https://gitlab.com/chromaway/ft4-lib/-/blob/development/rell/src/lib/ft4/core/accounts/module.rell#lines-722)

Checks if the auth descriptor args correspond to `single_sig_args` or `multi_sig_args`,
based on the descriptor's `auth_type`

Throws `"MULTISIG NEGATIVE REQUIREMENT"` if a multi-sig auth descriptor's
`required_signatures` is 0 or less

Throws `"MULTISIG REQUIREMENT TOO HIGH"` if a multi-sig
auth descriptor's `required_signature` parameter is greater than the number of signers

Throws `"UNSUPPORTED SIGNER"` if the signer's size does not match either:

* `EVM_ADDRESS_SIZE` length of 20 bytes
* `FT_PUBKEY_SIZE` length of 33 bytes

**Parameters**

* **auth\_descriptor** — the auth descriptor to check

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-rell/-f-t4%20-library/lib.ft4.core.accounts/validate_auth_descriptor_args.html)Generated API reference, mirrored from the live docs