Implement asynchronous task execution with result retrieval after connection loss

[istarwyh]

Currently, the MCP SDK doesn't provide a built-in mechanism for asynchronous task execution where the client can retrieve results after a connection loss. This feature would be valuable for long-running tasks or scenarios where network stability is a concern.

Feature request:
Implement a way for MCP Client to submit an asynchronous task to MCP Server, disconnect, and later retrieve the task execution results.

Proposed workflow:

1. MCP Client submits a task to MCP Server
2. MCP Server returns a unique task ID
3. MCP Client can disconnect
4. MCP Server continues processing the task
5. MCP Client can reconnect later and query the task status/results using the task ID

Possible implementation ideas:

• Add a new API endpoint for submitting async tasks
• Implement a task queue on the server side
• Add a method to query task status and retrieve results
• Consider using a persistent storage solution for task results

This feature would enhance MCP's capabilities for handling long-running tasks and improve resilience in unstable network conditions.

Any thoughts or suggestions on how to best implement this feature would be appreciated.

[felixweinberger]

There's a work in progress SEP & PR for this, so closing this to consolidate discussion on those items:

modelcontextprotocol/modelcontextprotocol#1391
#1398