This document discusses using Linked Data Notifications (LDN) to enable multi-agent interactions on the web through decentralized semantic messaging. LDN allows agents to send and receive notifications by posting RDF-formatted messages to other agents' HTTP-accessible inboxes. This provides a standardized way for agents to discover, communicate with, and coordinate with each other using common web technologies and Linked Data principles. However, challenges remain in promoting adoption of semantic messaging among web agents and linking existing agent communication standards to web protocols.