Fix multiline descriptions

gpt_json/fn_calling.py

@@ -15,11 +15,8 @@ def parse_function(fn: Callable) -> Dict[str, Any]:
     API Reference: https://platform.openai.com/docs/api-reference/chat/create
 
     """
-    docstring = getdoc(fn) or ""
-    lines = docstring.strip().split("\n")
-    description = lines[0] if lines else None
-
     parameter_type = get_argument_for_function(fn)
+    description = get_function_description(fn)
 
     # Parse the parameter type into a JSON schema
     parameter_schema = model_to_parameter_schema(parameter_type)
@@ -43,6 +40,32 @@ def function_to_name(fn: Callable) -> str:
     return fn.__name__
 
 
+def get_function_description(fn: Callable) -> str:
+    """
+    The description of a function is everything before an empty linebreak.
+
+    For instance:
+
+    ```
+    A
+    B
+
+    C
+    ```
+
+    Would return "A B"
+
+    """
+    docstring = getdoc(fn) or ""
+    lines = docstring.strip().split("\n")
+    description_lines = []
+    for line in lines:
+        if not line.strip():
+            break
+        description_lines.append(line.strip())
+    return " ".join(description_lines)
+
+
 def get_argument_for_function(fn: Callable) -> Type[BaseModel]:
     """
     Function definitions are expected to have one argument, which is a pydantic BaseModel that captures

gpt_json/tests/shared.py

@@ -26,12 +26,11 @@ class GetCurrentWeatherRequest(BaseModel):
 
 
 def get_current_weather(request: GetCurrentWeatherRequest):
-    """
-    Get the current weather in a given location.
-    Second line should also be included.
+    """Test description"""
 
-    The rest of the docstring should be omitted.
-    """
+
+async def get_current_weather_async(request: GetCurrentWeatherRequest):
+    """Test description"""
 
 
 def get_weather_additional_args(request: GetCurrentWeatherRequest, other_args: str):

gpt_json/tests/test_fn_calling.py

@@ -2,15 +2,30 @@
 
 import pytest
 
-from gpt_json.fn_calling import get_base_type, parse_function
+from gpt_json.fn_calling import get_base_type, get_function_description, parse_function
 from gpt_json.tests.shared import (
     UnitType,
     get_current_weather,
+    get_current_weather_async,
     get_weather_additional_args,
     get_weather_no_pydantic,
 )
 
 
+def multi_line_description_fn():
+    """
+    Test
+    description
+
+    Hidden
+    description
+    """
+
+
+def single_line_description_fn():
+    """Test description"""
+
+
 @pytest.mark.parametrize(
     "incorrect_fn",
     [
@@ -29,18 +44,31 @@ def test_get_base_type():
     assert get_base_type(Union[UnitType, None]) == UnitType
 
 
-def test_parse_function():
+def test_get_function_description():
+    assert get_function_description(multi_line_description_fn) == "Test description"
+    assert get_function_description(single_line_description_fn) == "Test description"
+
+
+@pytest.mark.parametrize(
+    "function,expected_name",
+    [
+        (get_current_weather, "get_current_weather"),
+        (get_current_weather_async, "get_current_weather_async"),
+    ],
+)
+def test_parse_function(function, expected_name: str):
     """
     Assert the formatted schema conforms to the expected JSON-Schema / GPT format.
     """
-    parse_function(get_current_weather) == {
-        "name": "get_current_weather",
-        "description": "Get the current weather in a given location. Second line should also be included.",
+    assert parse_function(function) == {
+        "name": expected_name,
+        "description": "Test description",
         "parameters": {
             "type": "object",
             "properties": {
                 "location": {
                     "type": "string",
+                    "title": "Location",
                     "description": "The city and state, e.g. San Francisco, CA",
                 },
                 "unit": {