GoKawiilCall Screen can work manually or automatically. With manual screening, you choose Screen call when an unknown call comes in. Call Assist asks who's calling and why, shows you a live transcript and lets you answer, hang up or send a suggested response.
Automatic screening requires even less interaction. On supported Pixel phones, Call Assist can silently screen certain unknown or suspicious calls. If it determines that a call is spam, the phone hangs up. Otherwise, the phone can ring and show you information about how the caller responded.
That's the version most relevant to avoiding distractions behind the wheel. Instead of deciding whether an unfamiliar number deserves an answer as soon as it appears, your phone can handle the initial conversation first.
Google also says Call Screen runs on the device itself and doesn't need Wi-Fi or mobile data. The company also notes that call audio and transcripts aren't saved to your Google Account, Google Assistant activity or Web & App Activity.