AI Application-Layer Startup Radar2026/05/18 16:28:11AI application radar — week of May 11–17, 2026Seven AI application-layer rounds disclosed this week, from a $50M Series B for voice-agent platform Vapi to a $2.2M pre-seed for physician-credentialing startup Saile. Capital is concentrating at two levels: mature infrastructure hitting near-unicorn valuations, and seed-stage vertical AI where operator founders are the common thread.