Update pkg/github/repositories.go

Co-authored-by: Copilot <[email protected]>

Author: mattdholloway

pkg/github/repositories.go

@@ -37,8 +37,8 @@ func GetCommit(getClient GetClientFn, t translations.TranslationHelperFunc) (too
 				mcp.Required(),
 				mcp.Description("Commit SHA, branch name, or tag name"),
 			),
-			mcp.WithBoolean("include_diff",
 				mcp.Description("Whether to include file diffs and stats in the response. Default is true."),
+				mcp.DefaultBool(true),
 			),
 			WithPagination(),
 		),