mcp: replace type struct{} with any for user-defined fields #334
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This change adopts a clearer convention:
- any is used for fields where the structure is defined by
the client or server implementer.
- struct{} is reserved for placeholder fields to be defined
by the MCP spec in the future.
The "Experimental" fields in "ClientCapabilities" and
"ServerCapabilities" now use "map[string]any". This allows
clients and servers to negotiate custom capabilities that contain
complex data, rather than being restricted to a simple on/off flag.
The "Metadata" field in "CreateMessageParams" was also changed to
"any" to properly serve its purpose as a flexible container for
server-defined data.
Collaborator
Author
|
Some reference that might be helpful: LSP Client Capability Experimental definition in typescript The go LSP client used a slice (array) for some feature. LSP Client Capability Experimental definition in go |
Contributor
|
You should remove the "PR Guideline" section from the commit message. (Can wait until you commit.) |
jba
approved these changes
Aug 20, 2025
Collaborator
Author
|
Just remove anything below the PR Guideline, does this look good to you? |
yasomaru
pushed a commit
to yasomaru/go-sdk
that referenced
this pull request
Aug 28, 2025
…textprotocol#334) This change adopts a clearer convention: - any is used for fields where the structure is defined by the client or server implementer. - an named empty struct type is the place holder type to be defined by the MCP spec in the future. The "Experimental" fields in "ClientCapabilities" and "ServerCapabilities" now use "map[string]any". This allows clients and servers to negotiate custom capabilities that contain complex data, rather than being restricted to a simple on/off flag. The "Metadata" field in "CreateMessageParams" was also changed to "any" to properly serve its purpose as a flexible container for server-defined data.
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This change adopts a clearer convention:
The "Experimental" fields in "ClientCapabilities" and "ServerCapabilities" now use "map[string]any". This allows clients and servers to negotiate custom capabilities that contain complex data, rather than being restricted to a simple on/off flag.
The "Metadata" field in "CreateMessageParams" was also changed to "any" to properly serve its purpose as a flexible container for server-defined data.