Posting to Reddit from an agent

Reddit writes fail for agents in ways that look like bugs but aren't. This skill exists because the naive approach — a scripted HTTP client, or Playwright/Puppeteer launching its own browser — hits walls that no amount of retry logic fixes. Understanding why saves you from a long debugging spiral.

The architecture, and why it is the way it is

rdtx attaches over CDP to a Chrome that the human launched, and issues writes as same-origin fetch calls from inside the logged-in page.

Three things make this work, each of which was established by measurement:

1. The automation flag is set at launch, not by attaching. Puppeteer and Playwright pass --enable-automation, which sets navigator.webdriver = true. If Chrome is started with only --remote-debugging-port, that flag is never set, and attaching afterward leaves navigator.webdriver === false. So a human-launched Chrome plus a later CDP attach presents an ordinary browser surface.