This module is meant to be used inside of a frida module.
An easy injector can be found here: frida-inject

It will give you access to the mono c functions, exported by mono.
For easy use, there are some helper methods you should check out.

The functions exposed by "MonoApi" are "ExNativefunctions".
They have some more properties for easy use. See: frida-ex-nativefunction

import { MonoApiHelper } from 'frida-mono-api'

MonoApiHelper.AssemblyForeach(assembly => console.log(assembly))

import { MonoApi } from 'frida-mono-api'

const domain = MonoApi.mono_domain_get()