What format for Post data

I have tried POSTing some data, however the server gets blank data. What is the expected format for POST, and PUT data?
`title="My Good Book"` and similar combinations don't work

Perhaps a line in the README would help out.
Thanks!

Start by reading the README and reviewing the documented command usage for POST and PUT requests. Determine the expected data format from the project's existing behavior, then update the README with a clear example and verify that it explains how submitted data reaches the server.

Written by the indexing model from the issue text.