awslabs
aws-diagram-mcp-server: Windows does not support signal.SIGALRM
Describe the bug
The diagram MCP Server does not work on Windows. generate_diagram fails with the following error: {"status": "error", "path": null, "message": "Error generating diagram: AttributeError: module 'signal' has no attribute 'SIGALRM'"}
The package is using signal.SIGALRM for timeout handling, which isn't available on Windows.
Expected Behavior
The generate_diagram function should work on Windows.
Current Behavior
The generate_diagram function throws an error on Windows.
Reproduction Steps
- Install server in VS Code on Windows
- Ask Cline to create a Graphviz diagram using the server
Possible Solution
No response
Additional Information/Context
No response
OS
Windows
Server
aws-diagram-mcp-server
Server Version
No response
Region experiencing the issue
none
Other information
No response
Service quota
- [x] I have reviewed the service quotas for this construct
I am also facing the same error {"status": "error", "path": null, "message": "Error generating diagram: AttributeError: module 'signal' has no attribute 'SIGALRM'"}
Related: https://github.com/awslabs/mcp/issues/162
Windows support
@scottschreckengaust @MichaelWalker-git I just ran into this same exact error today when using the diagram MCP server on a Windows machine. This has been an issue since May and there was a fix created, but it was closed & the branch deleted. Can we please get this resolved once and for all?
{ "status": "error", "path": null, "message": "Error generating diagram: AttributeError: module 'signal' has no attribute 'SIGALRM'" }
@krokoko @MichaelWalker-git Can you assist in getting this resolved or should I open up a new issue to address this?
Still an issue,
{
"status": "error",
"path": null,
"message": "Error generating diagram: AttributeError: module 'signal' has no attribute 'SIGALRM'"
}
Ran using VSCode with the tool generate_diagram
