Structured output with tool calling

Fixed:

Structured output not working in conjunction with tool calling when calling generate
ollamaChat constructor erroring with ResponseFormat NVP set to a struct

Added:

Double-quotes to .githooks/pre-commit to handle spaces in repo path

Author: ccreutzi

.githooks/pre-commit

@@ -2,7 +2,7 @@
 
 set -e
 
-cd $(git rev-parse --show-toplevel)
+cd "$(git rev-parse --show-toplevel)"
 pwd
 
 # For all commits of mlx files, create corresponding Markdown (md) files.

azureChat.m

@@ -292,7 +292,9 @@
                 error("llms:apiReturnedError",llms.utils.errorMessageCatalog.getMessage("llms:apiReturnedError",err));
             end
 
-            text = llms.internal.reformatOutput(text,nvp.ResponseFormat);
+            if ~isempty(text)
+                text = llms.internal.reformatOutput(text,nvp.ResponseFormat);
+            end
         end
     end
 

ollamaChat.m

@@ -94,7 +94,7 @@
                 nvp.MinP                           {llms.utils.mustBeValidProbability} = 0
                 nvp.TopK                     (1,1) {mustBeReal,mustBePositive} = Inf
                 nvp.StopSequences                  {llms.utils.mustBeValidStop} = {}
-                nvp.ResponseFormat           (1,1) string {mustBeMember(nvp.ResponseFormat,["text","json"])} = "text"
+                nvp.ResponseFormat                 {llms.utils.mustBeResponseFormat} = "text"
                 nvp.TimeOut                  (1,1) {mustBeNumeric,mustBeReal,mustBePositive} = 120
                 nvp.TailFreeSamplingZ        (1,1) {mustBeNumeric,mustBeReal} = 1
                 nvp.StreamFun                (1,1) {mustBeA(nvp.StreamFun,'function_handle')}

openAIChat.m

@@ -80,7 +80,7 @@
 %       TimeOut              - Connection Timeout in seconds.
 %
 
-% Copyright 2023-2024 The MathWorks, Inc.
+% Copyright 2023-2025 The MathWorks, Inc.
 
     properties(SetAccess=private)
         %MODELNAME   Model name.
@@ -270,7 +270,9 @@
                 error("llms:apiReturnedError",llms.utils.errorMessageCatalog.getMessage("llms:apiReturnedError",err));
             end
 
-            text = llms.internal.reformatOutput(text,nvp.ResponseFormat);
+            if ~isempty(text)
+                text = llms.internal.reformatOutput(text,nvp.ResponseFormat);
+            end
         end
     end
 

tests/hopenAIChat.m

@@ -172,5 +172,23 @@ function keyNotFound(testCase)
             unsetenv("AZURE_OPENAI_API_KEY");
             testCase.verifyError(testCase.constructor, "llms:keyMustBeSpecified");
         end
+
+        function toolCallingAndStructuredOutput(testCase)
+            import matlab.unittest.constraints.HasField
+
+            f = openAIFunction("addTwoNumbers", "Add two numbers");
+            f = addParameter(f, "a");
+            f = addParameter(f, "b");
+
+            responseFormat = struct("llmReply", "The LLM returns a struct if no tool is called");
+            
+            chat = testCase.constructor("You are a helpful agent.", ...
+                Tools=f, ResponseFormat=responseFormat);
+            prompt = "What's 1+1?";
+            
+            [reply, complete] = testCase.verifyWarningFree(@() generate(chat, prompt));
+            testCase.verifyEmpty(reply);
+            testCase.verifyThat(complete, HasField("tool_calls"));
+        end
     end
 end

tests/hstructuredOutput.m

@@ -4,11 +4,16 @@
 %   Copyright 2023-2025 The MathWorks, Inc.
 
     properties(Abstract)
+        constructor
         structuredModel
     end
 
     methods(Test)
-        % Test methods
+        function constructWithStructuredOutput(testCase)
+            responseFormat = struct("llmReply","This is an example struct");
+            testCase.verifyWarningFree(@() testCase.constructor(ResponseFormat=responseFormat));
+        end
+
         function generateWithStructuredOutput(testCase)
             import matlab.unittest.constraints.ContainsSubstring
             import matlab.unittest.constraints.StartsWithSubstring

tests/tollamaChat.m

@@ -424,11 +424,11 @@ function queryModels(testCase)
 invalidConstructorInput = struct( ...
     "InvalidResponseFormatValue", struct( ...
         "Input",{{"ResponseFormat", "foo" }},...
-        "Error", "MATLAB:validators:mustBeMember"), ...
+        "Error", "llms:incorrectResponseFormat"), ...
     ...
     "InvalidResponseFormatSize", struct( ...
         "Input",{{"ResponseFormat", ["text" "text"] }},...
-        "Error", "MATLAB:validation:IncompatibleSize"), ...
+        "Error", "MATLAB:validators:mustBeTextScalar"), ...
     ...
     "InvalidStreamFunType", struct( ...
         "Input",{{"StreamFun", "2" }},...