# assertPieceValid

## Type Aliases

| Type Alias | Description |
| ------ | ------ |
| [ErrorType](/reference/filoz/synapse-core/utils/namespaces/assertpiecevalid/type-aliases/errortype/) | - [InvalidUploadSizeError](/reference/filoz/synapse-core/errors/classes/invaliduploadsizeerror/) when the PieceCID size is below [SIZE\_CONSTANTS.MIN\_UPLOAD\_SIZE](/reference/filoz/synapse-core/utils/variables/size_constants/#min_upload_size) or above [SIZE\_CONSTANTS.MAX\_UPLOAD\_SIZE](/reference/filoz/synapse-core/utils/variables/size_constants/#max_upload_size) - `Error` when the piece metadata exceeds the contract limits |