instead of having an openai => google translation layer, just add sister functions to the types that construct the google request just like openai's

openai.go

@@ -39,7 +39,7 @@ func (o openaiImpl) newRequestToOpenAIRequest(request Request) openai.ChatComple
 					Name:        tool.Name,
 					Description: openai.String(tool.Description),
 					Strict:      openai.Bool(tool.Strict),
-					Parameters:  tool.Parameters.FunctionParameters(),
+					Parameters:  tool.Parameters.OpenAIParameters(),
 				},
 			})
 		}