fix: generate default schema for tools with no params

[vincent0426]

Motivation and Context

closes #445

provide empty object json schema when there is no params for a tool, following https://github.com/modelcontextprotocol/typescript-sdk/blob/c94ba4b43cd305e39d88985c73d6b9bc1153da84/src/server/mcp.ts#L1202-L1205

How Has This Been Tested?

Breaking Changes

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context

[jokemanfire]

If this pr has been merged , the empty struct will be updated , how about wait for the newest schema description release?
https://github.com/modelcontextprotocol/modelcontextprotocol/pull/881/files#diff-b562e63d9fb1f6bbb6ddf2807a7f4e9558662e454b33076540a053ae55e46fc0

[asm89]

@jokemanfire Ideally this fix is merged, because it seems like clients in the wild do expect the object type to be present. Servers using rmcp 0.7.0 are not compatible with many clients due to the {} being used to signal empty parametrs.

[jokemanfire]

Then please add a todo comment. This should be updated according to the new specifications soon.

[alexhancock]

It LGTM now if also OK with @jokemanfire

The commit message input: fix: generate default schema for tools with no params could work

[vincent0426]

@jokemanfire any reason that CI doesn't pass? thanks

[jokemanfire]

@jokemanfire any reason that CI doesn't pass? thanks

It should be CI's problem ,I will check.

[jokemanfire]

#458 fix rustdoc build by scoping