Tooling API - Can't create objects

When I try to create an object such as ‘ApexClass’, I get the following error:

TypeError: this._createSingle is not a function At: at Tooling.Connection.insert.Connection.create

This is the code: conn.login(username, password + securityToken, function(err) { if (!err) { const apexBody = [ "public class TestApex {", " public string sayHello() {", " return 'Hello';", " }", "}"].join('\n'); conn.tooling.sobject('ApexClass').create({ body: apexBody }, function(err, res) { if (err) { return console.error(err); } console.log(res); }); } });

[aust1nz]

I had the same issue with JSforce v 1.9.1. I downgraded to 1.8.5 and was able to use the Tooling API as expected.

[superkensington]

Can confirm that this is still an issue in 2.0.0-beta.19. Unable to use the Tooling API functionality for DML operations, throws the error TypeError: this._ensureVersion is not a function.