encodeURIComponent on client and decodeURIComponent on server

could someone criticize me this approach:

I want to send a JSON object in a GET method but the body is not available, so I'm encoded the JSON in the client and decoded in the server, like this:

// on client
 let query = {
    subject: subject,
    sources: sources
  }
query = encodeURIComponent(JSON.stringify(query))
console.log(encoded);

// on server
const { query } = url.parse(req.url)
decodedQuery = decodeURIComponent(query)

it just works, but people use several libraries like querystring and query-string or manually build the query string.

So why don't do what I'm doing?

Regards