Do we need a fully typed Server-Client Protocol?

I have this idea, and a prototype in the works, that allows our team to write code (once only) for the "bridge" between any client and server, that can work over http (request - response type), sockets (event based) or even RTC (for a p2p architecture), and that comes fully typed on both ends.

The end result is almost like an SDK that abstracts the whole networking details (url routes, http methods, communication protocols (http, socket, etc.), outside of the business logic both on client and server. Probably a fully typed RPC framework is even more like it.

It currently only works in typescript (browser and node), and all the checks happen at runtime so there's no need to write definitions or schemas, just regular code that lives in a separate library/repository and imported at build time. In the future it could be expanded to other languages as well.

This is an example:

server code

import { AsyncErr, AsyncOk } from 'ts-async-results';
import { init } from './pipeline/server';

const pipeline = init({
  // TODO: The port should actually come from the 
  // pipeline codebase so it's bundled together with
  // the client on the same version
  port: 8080,
})

pipeline.user.onRequest('single', async (request) => {
 // handle the onRequest and return an 
 // AsyncOk or Async Err, to get sent over the wire. 
 // This is the analog of res.send(data) in express
  
 cost myUser = await db.getUser({id: request.id});

 if (myUser) {
   // Look into https://github.com/movesthatmatter/ts-async-results 
   // for more info on the ts-async-result
   return new AsyncOk(myUser)
 }

  return new AsyncErr({
    type: 'InexistentResource',
    content: request.id,
  })
})

client code

import { init } from './pipeline/client'

const pipeline = init({
  httpUrl: 'https://localhost',
  wssUrl: 'https://localhost'
})

pipeline.user.request('single', { id: '2' })
   .map((user) => {
     // success code
      console.log('user', user);
   })
   .mapErr((e) => { 
       // fully typed errors

       if (e.type === 'InexistentResource') {
           // handle 
       }

       // handle otherwise
   })

Does this sound appealing to anybody? If so please leave a comment or feedback below and I'll be more than happy to give more details.