chat: make tool description and parameters optional per OpenAI spec (#18478)

* chat: make tool description and parameters optional per OpenAI spec

Per the OpenAI API specification, both 'description' and 'parameters'
fields in tool function definitions are optional. Previously, the parser
would throw an exception if these fields were missing.

Attempts to fix #17667

* refactor: use value() for cleaner optional field access

diff --git a/common/chat.cpp b/common/chat.cpp
index be44c8abb0b908a9a981e5b6358a3bf0b7e617bc..7e940695bdab4302189a50853ea726ff05da2bce 100644 (file)
--- a/common/chat.cpp
+++ b/common/chat.cpp
@@ -380,8 +380,8 @@ std::vector<common_chat_tool> common_chat_tools_parse_oaicompat(const json & too
                 const auto & function = tool.at("function");
                 result.push_back({
                     /* .name = */ function.at("name"),
-                    /* .description = */ function.at("description"),
-                    /* .parameters = */ function.at("parameters").dump(),
+                    /* .description = */ function.value("description", ""),
+                    /* .parameters = */ function.value("parameters", json::object()).dump(),
                 });
             }
         }

diff --git a/tests/test-chat.cpp b/tests/test-chat.cpp
index a78627604e79881b7a86e5f6d34d4d11b9ea2f3d..a07c81fba62c2067cebcf4372fa6082c056ee4b1 100644 (file)
--- a/tests/test-chat.cpp
+++ b/tests/test-chat.cpp
@@ -724,6 +724,30 @@ static void test_tools_oaicompat_json_conversion() {
             "]"
         ),
         common_chat_tools_to_json_oaicompat<json>({special_function_tool}).dump(2));
+
+    {
+        auto tools_no_params = common_chat_tools_parse_oaicompat(json::parse(
+            R"([{"type": "function", "function": {"name": "test_func", "description": "A test"}}])"));
+        assert_equals((size_t) 1, tools_no_params.size());
+        assert_equals(std::string("test_func"), tools_no_params[0].name);
+        assert_equals(std::string("A test"), tools_no_params[0].description);
+        assert_equals(std::string("{}"), tools_no_params[0].parameters);
+    }
+    {
+        auto tools_no_desc = common_chat_tools_parse_oaicompat(json::parse(
+            R"([{"type": "function", "function": {"name": "test_func", "parameters": {"type": "object"}}}])"));
+        assert_equals((size_t) 1, tools_no_desc.size());
+        assert_equals(std::string("test_func"), tools_no_desc[0].name);
+        assert_equals(std::string(""), tools_no_desc[0].description);
+    }
+    {
+        auto tools_minimal = common_chat_tools_parse_oaicompat(json::parse(
+            R"([{"type": "function", "function": {"name": "test_func"}}])"));
+        assert_equals((size_t) 1, tools_minimal.size());
+        assert_equals(std::string("test_func"), tools_minimal[0].name);
+        assert_equals(std::string(""), tools_minimal[0].description);
+        assert_equals(std::string("{}"), tools_minimal[0].parameters);
+    }
 }
 
 static void test_template_output_parsers() {