fix: SSE client hangs after 30 seconds

[mrene]

In #55, an option was added to set an sse read timeout. This timeout, however, applies to the entire readSSE function which is responsible for receiving messages from the server after the client's initialization. Because of this, any SSE client stops working 30 seconds after initialization. Any request hangs because no responses are being processed.

The original author mentioned parity with the Python SDK as a justification for adding this option. However, in the python SDK, the timeout applies to a specific call, not to the entire message loop. In Go, callers can directly create their context with a given timeout or deadline without a specific option for timeouts.

For this reason, I would recommend removing the option altogether.

Summary by CodeRabbit

• Refactor
  • Updated real-time event stream handling by removing the configurable read timeout setting. SSE connections now conclude based on connection termination signals rather than a preset timeout, resulting in a more straightforward and consistent streaming experience.

[coderabbitai[bot]]

Walkthrough

This pull request simplifies the SSE client setup by removing the timeout mechanism previously used to terminate read operations. The changes include removing the sseReadTimeout field from the SSEMCPClient struct and eliminating the WithSSEReadTimeout function from client initialization. Additionally, the readSSE method is updated to check for the closure of the done channel instead of using a context with a timeout, thereby altering the control flow for handling long-running SSE connections.

Changes

File(s)	Changes
client/sse.go	Removed the sseReadTimeout field from the SSEMCPClient struct and the WithSSEReadTimeout function. Modified NewSSEMCPClient to omit the default timeout and updated readSSE to rely on the done channel instead of a context timeout.

Possibly related PRs

• mark3labs/mcp-go#65: Modifies the readSSE method to enhance its implementation and error handling, directly relating to the control flow changes made in this PR.

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[ezynda3]

I am in favor of removing this in favor of a more Go aligned method of dealing with timeouts. However, maybe it would be good to add a test or, at a minimum, some documentation about how someone could use context to handle timeouts in the README

[yp05327]

Are there any updates? The client is borken, should be fixed ASAP.

[mrene]

Are there any updates? The client is borken, should be fixed ASAP.

If it helps I have a tag with the fix that you can replace in go.mod pending this being merged:

replace github.com/mark3labs/mcp-go v0.17.0 => github.com/mrene/mcp-go v0.17.0-ssefix