Standardizing Session State Management for Stateful Remote MCP

[cploujoux]

With HTTP stream + SSE becoming the standard transport mechanism for remote MCP servers, there is a need to define how session state should be structured, persisted, and synchronized.
This proposal addresses this gap by providing a comprehensive standard for session state management.

Goal:

• Standardization: Create a consistent approach to session state management that can be implemented across different MCP server architectures
• Enable clients to connect to different MCP server implementations with predictable state handling behavior
• Facilitate implementation of advanced stateful features
• Design state management that works efficiently in horizontally-scaled environments

Output:

• Session State table schema
• Interface to develop new session storage types
• Sample of implementation with sqlite/postgres/mysql storage

[patwhite]

One big item to add here is general guidance on session lifetimes / lifecycle. There are a few places in the spec this isn't super clear - is a session officially initialized after the initialize message but before the initialized message? Is there a timeout when you clear the session after initialize but if initialized never comes in? What's a best practice for session life? 10 minutes?

[Joffref]

For reference, here's the related PR: #34