We love these tools but they were designed for testing, not for automation. They are too low-level to be used as they are by AI.
For example, the playwright MCP is very unreliable and inefficient to use. To mention a few issues, it does not correctly pierce through the different frames and does not handle the variety of edge cases that exist on the web. This means that it can't click on the button it needs to click on. Also, because it lacks control over the context design, it cannot optimize for contextual operations and your LLM trace gets polluted with incredible amount of useless tokens. This increases cost, task complexity for the LLM, and latency
On top of that, these tools rely on the accessibility tree, which is just not a viable approach for a huge number of websites