The simplest way to receive debug information is to set the log client option to console.

const octokit = require("@octokit/rest")({
log: console,
});
octokit.request("/");

This will log

request { method: 'GET',
baseUrl: 'https://api.github.com',
headers:
{ accept: 'application/vnd.github.v3+json',
'user-agent':
'octokit.js/0.0.0-development Node.js/10.15.0 (macOS Mojave; x64)' },
request: {},
url: '/' }
GET / - 200 in 514ms

If you like to support a configurable log level, we recommend using the console-log-level module

const octokit = require("@octokit/rest")({
log: require("console-log-level")({ level: "info" }),
});
octokit.request("/");

This will only log

GET / - 200 in 514ms