set 'tool_choice_force' to specify a particular function

src/api/chat_completion.rs

@@ -61,10 +61,14 @@ pub struct ChatCompletionRequest {
     #[builder(default, setter(into))]
     #[serde(skip_serializing_if = "Vec::is_empty")]
     tools: Vec<Tool>,
-    /// Controls which (if any) function is called by the model. none means the model will not call a function and instead generates a message. auto means the model can pick between generating a message or calling a function. Specifying a particular function via {"type: "function", "function": {"name": "my_function"}} forces the model to call that function. none is the default when no functions are present. auto is the default if functions are present.
+    /// Controls which (if any) function is called by the model. none means the model will not call a function and instead generates a message. auto means the model can pick between generating a message or calling a function. none is the default when no functions are present. auto is the default if functions are present. Leave it None if tool_choice_force is Some.
     #[builder(default, setter(strip_option))]
     #[serde(skip_serializing_if = "Option::is_none")]
     tool_choice: Option<ToolChoice>,
+    /// Just like tool_choice but specify a particular function via {"type: "function", "function": {"name": "my_function"}} to force the model to call that function.
+    #[builder(default, setter(strip_option))]
+    #[serde(skip_serializing_if = "Option::is_none", rename = "tool_choice")]
+    tool_choice_force: Option<SpecifiedToolChoice>,
     /// A unique identifier representing your end-user, which can help OpenAI to monitor and detect abuse.
     #[builder(default, setter(strip_option, into))]
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -77,10 +81,18 @@ pub enum ToolChoice {
     #[default]
     None,
     Auto,
-    // TODO: we need something like this: #[serde(tag = "type", content = "function")]
-    Function {
-        name: String,
-    },
+}
+
+/// {"type: "function", "function": {"name": "your_function"}}
+#[derive(Debug, Clone, Serialize)]
+#[serde(rename_all = "snake_case", tag = "type")]
+pub enum SpecifiedToolChoice {
+    Function { function: FunctionName },
+}
+
+#[derive(Debug, Clone, Serialize)]
+pub struct FunctionName {
+    name: String,
 }
 
 #[derive(Debug, Clone, Serialize)]
@@ -111,6 +123,7 @@ pub struct ChatResponseFormatObject {
 pub enum ChatResponseFormat {
     Text,
     #[default]
+    #[serde(rename = "json_object")]
     Json,
 }
 
@@ -374,11 +387,12 @@ mod tests {
     }
 
     #[test]
-    #[ignore]
     fn chat_completion_request_tool_choice_function_serialize_should_work() {
         let req = ChatCompletionRequestBuilder::default()
-            .tool_choice(ToolChoice::Function {
-                name: "my_function".to_string(),
+            .tool_choice_force(SpecifiedToolChoice::Function {
+                function: FunctionName {
+                    name: "my_function".to_string(),
+                },
             })
             .messages(vec![])
             .build()
@@ -393,6 +407,7 @@ mod tests {
                   "name": "my_function"
                 }
               },
+              "model": "gpt-3.5-turbo-1106",
               "messages": []
             })
         );