This tool is a wrapper on web3.js used to generate sample (mock) RLP encoded transactions. Will be helpful in testing functions which take RLP encoded transactions as inputs.
The number of tranasactions you want must be passed as a command line argument.
A file consisting of the transactions will be created called transactions-example-file.json.
The field rawTransaction is the RLP encoded transaction.
Here is a brilliant write-up on RLP encodings that you can read to understand RLP encoding (not decoding) in depth.
A Handy tool to decode these RLP encoded transactions can be found here.
Another example of decoding an RLP encoded transaction can be found here.