Most bugs that make it into a released indie game aren't exotic edge cases, they're the boring kind: a collectible placed slightly out of reach, a trigger that doesn't fire if you approach from the wrong angle, a level that's technically unbeatable because of a fence gap nobody noticed. AI-driven playtesting exists specifically to catch this category, fast, and before a human ever sits down with the build.
What an AI playtester actually does
It's an agent that plays your build the way a player would, moving, jumping, interacting, and reports what happened: did it reach the end, did it get stuck, did anything throw an error. Run it after every change instead of waiting for a scheduled QA pass, and it turns "is this level still beatable" from a question you find out the hard way into one you get an answer to in minutes.
What it's actually good at
Anything with an objective, checkable outcome: can the level be completed, does this quest trigger fire, does the game survive to the credits without crashing. These are exactly the questions a script can answer definitively, which is why this is such a good fit for automated iteration loops, generate a change, have the agent verify it didn't break completion, ship or roll back.
What it still can't tell you
Whether the level is fun. Whether the difficulty curve feels fair. Whether a joke lands. An AI playtester can confirm your game works. It has no opinion on whether anyone will enjoy playing it, and treating "the automated test passed" as "this is ready to ship" is how technically-functional-but-boring games get released.
The actual workflow that works
Use automated playtesting as a gate that catches broken states early and often, freeing your human testers, or yourself, from re-checking "is this still completable" every single iteration. Spend the human time you just got back on the question the machine can't answer: does this feel good to play. That division of labor, not replacement, is where this technology is actually useful right now.