Using the Conversations Inbox & Messaging API (https://developers.hubspot.com/docs/api/conversations/conversations) we can pull the body of an email, parse the content and create a contact in the CRM using the Contact API (https://developers.hubspot.com/docs/api/crm/contacts).

createContactfromConversationThread.js

//1. Import required libraries
const hubspot = require('@hubspot/api-client');
const axios = require('axios');

exports.main = async (event, callback) => {

  //2. Store threadID in variable, we'll use this to pull information
  const threadID = event.inputFields['hs_thread_id'];

  //3. Make a request to the conversations API to retrieve text - https://developers.hubspot.com/docs/api/conversations/conversations
   axios.get("https://api.hubapi.com/conversations/v3/conversations/threads/" + threadID + "/messages/?hapikey=" + process.env.HAPIKEY, {})
        .then((response) => { // Run code when we get response

     		console.log(response.data.results[1].text) //debugging can be removed

     		//4. Parse text and store data in variables
     		//4.1 Get email address
     		var email = response.data.results[1].text.match(/[a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9_-]+/);
     		console.log("Email address is: " + email);
     
     		//4.2 Get Name - (?<=TERM: )(.*) - JS doesn't support positive lookbehinds...
     		var name = response.data.results[1].text.match(/(?=name: )(.*)/);
     		console.log("Name is: " + name[1].split(" ")[1] + " " +  name[1].split(" ")[2]);
     		var fname = name[1].split(" ")[1];
    		var lname = name[1].split(" ")[2];
     
     		//4.3 Get phone number - (?<=Phone: )(.*)(?= Email:)
          	var phone = response.data.results[1].text.match(/(?=Phone: )(.*)/);
     		console.log("Phone is: " + phone[0].split(" ")[1]);

     		//4.4 Get message - (?<=Message: )(.*) - Could create engagement with this information
		    var message = response.data.results[1].text.match(/(?=Message: )(.*)/);
     		console.log("Message is: " + message[1].split(" ")[1]);
            console.log(message[0]);
          
     		//5. Create Contact using email address - https://developers.hubspot.com/docs/api/crm/contacts
            const hubspotClient = new hubspot.Client({
              apiKey: process.env.HAPIKEY
            });
     		
     		const properties = { 
              "email": email[0], 
              "firstname": fname, 
              "lastname": lname,
              "phone": phone[1].split(" ")[1]
            };
     
			const SimplePublicObjectInput = { properties };
            console.log('CONTACT CREATE');
     		hubspotClient.crm.contacts.basicApi.create(SimplePublicObjectInput).then(results => {
              console.log("SUCCESS: Contact created with email address: " + email[0]) // Success
            }).catch(error =>{
              console.log("ERROR: Contact not created"); // Error
            });
         
	}).catch(error=>{
		console.log(error);
  	})
}