We shipped a free Web Bot Auth verifier. Here's what makes L4 different from L3. Web Bot Auth is getting serious attention. Cloudflare's Thibault Meunier wrote the draft. Google Cloud Fraud Defense integrated it this week alongside SPIFFE for agent identity. The underlying spec is RFC 9421 HTTP Message Signatures, and the core idea is clean: every request carries an Ed25519 signature, the receiver resolves the signing key from a URL the agent provides, math confirms it. No sessions, no cookies, no handshake. We just shipped POST /v1/wba/verify at agentlair.dev. Free, anonymous, no signup. But we added something beyond what the RFC covers.…