modelcontextprotocol / modelcontextprotocol/csharp-sdk
AddSingleton does not work as expected
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Description
Describe the bug
When we register tool like AddSingleton(type, instance) and pass a singleton instance, it seems that the instance is being ignored and the library creates a new instance when it needs it.
I tried also AddSingleton using a factory method like this:
services.AddSingleton(toolType, provider => Activator.CreateInstance(toolType, this.m_compositionService));
A breakpoint to Activator.CreateInstance was never hit and the tool just created the instance of the tool.
To Reproduce
Steps to reproduce the behavior:
1.
Expected behavior
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Logs
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Additional context
We discussed the issue over email. Please feel free to contact me there if you need additional information. Thanks!
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
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- Open a pull request that references the issue number.
Research direction
Start by reproducing the reported AddSingleton(type, instance) and factory registrations in the SDK's service setup, using the supplied tool type and Activator.CreateInstance path. Compare whether the registered instance or factory is invoked when the tool is created; done means both registration forms are honored instead of silently creating another instance.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- csharp
- Domain
- backend-api-design
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100