Pipedream's MongoDB API connection not working?

Question

https://www.pipedream.com has an UI-assisted integration with MongoDB. It requires 4 values to connect to the API:

$username
$password
$database
$hostname

my default connect to app connection string is: mongodb+srv://<username>:<password>@cluster0.45xcf.mongodb.net/myFirstDatabase?retryWrites=true&w=majority

(yes, I'm using the default cluster0 and myFirstDatabase values here)

I get back this error response:

MongoAPIError
URI must include hostname, domain name, and tld

DETAILS
    at null.resolveSRVRecord (/tmp/ee/c_m4fDxGe5/node_modules/.pnpm/[email protected]/node_modules/mongodb/lib/connection_string.js:51:25)
    at null.connect (/tmp/ee/c_m4fDxGe5/node_modules/.pnpm/[email protected]/node_modules/mongodb/lib/operations/connect.js:32:57)
    at null.null (/tmp/ee/c_m4fDxGe5/node_modules/.pnpm/[email protected]/node_modules/mongodb/lib/mongo_client.js:127:35)
    at null.maybePromise (/tmp/ee/c_m4fDxGe5/node_modules/.pnpm/[email protected]/node_modules/mongodb/lib/utils.js:409:5)
    at MongoClient.connect (/tmp/ee/c_m4fDxGe5/node_modules/.pnpm/[email protected]/node_modules/mongodb/lib/mongo_client.js:126:41)
    at Function.connect (/tmp/ee/c_m4fDxGe5/node_modules/.pnpm/[email protected]/node_modules/mongodb/lib/mongo_client.js:190:36)
    at Object.run (/steps/mongodb.js:19:38)
    at global.executeComponent (/var/task/launch_worker.js:171:53)
    at MessagePort.messageHandler (/var/task/launch_worker.js:653:28)
    
    

I'm trying to connect to the API with:

$username = {REDACTED}
$password = {REDACTED}
$database = myFirstDatabase
$hostname = cluster0

and it's not able to connect, but it does work connecting via mongosh, Compass, etc

here's the full Node.js code Pipedream uses to connect to MongoDB's API:

module.exports = defineComponent({
  props: {
    mongodb: {
      type: "app",
      app: "mongodb",
    }
  },
  async run({steps, $}) {
    const MongoClient = require('mongodb').MongoClient
    
    const {
      database,
      hostname,
      username,
      password,
    } = this.mongodb.$auth
    
    const url = `mongodb+srv://${username}:${password}@${hostname}/test?retryWrites=true&w=majority`
    const client = await MongoClient.connect(url, { 
      useNewUrlParser: true, 
      useUnifiedTopology: true 
    })
    
    const db = client.db(database)
    // Enter your target collection as a parameter to this step
    this.res = await db.collection(params.collection).insertOne({ name: "Luke Skywalker" })
    
    await client.close()
  },
})

Just don't understand why it won't connect. I can confirm the username and password aren't the problem.