Events Notifications in MCP | Aman Singh | MCP Release Party - Seattle
The talk introduces a proposed protocol extension for MCP (Messaging/Communication Protocol) designed to enable structured event streams. Currently, MCP only provides lightweight notifications that something has changed without specifying *what* changed or providing a payload. The new Events feature allows agents to subscribe to real-world events (e.g., incidents, emails), supporting three delivery modes—polling, push, and webhooks—to ensure reliable, low-latency communication while maintaining stateless server architecture.
Key takeaways
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Structured Event Streams
2:03
Events allow MCP servers to declare event types with a name, input schema for subscription parameters, payload schema, and supported delivery modes. This moves beyond simple URI notifications to structured data payloads.
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Three Delivery Modes
4:00
The proposed system supports three non-mandatory delivery methods: Simple Polling (self-contained requests using a cursor), Push (for low-latency, long-held connections), and Webhooks (server posts events to a client-provided URL).
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Stateless Architecture
6:25
The new design maintains MCP server statelessness. Polling is inherently stateless, allowing servers to sit behind load balancers and scale horizontally. The SDKs are expected to abstract the complexity of managing these modes for developers.