Tool calls support improvements

[mario7421]

Tool calls support improvements

• Handle previous messages that contain tool calls and add them to the context (previously they were considered as empty messages);
• Accept messages that have no content but only tool calls;
• Minor improvements in prompt template for tool calls for Hermes 3.

I have tested the new version using a toy example, but I did not run or modified the tests included in the repository.

[mario7421]

Example of prompt for a conversation with multiple tool calls:
<|im_start|>system
You are a function calling AI model. You are provided with function signatures within XML tags. You may call one or more functions to assist with the user query. Don't make assumptions about what values to plug into functions. Here are the available tools: [{"type":"function","function":{"name":"get_flight_info","description":"Get flight information between two locations","parameters":{"type":"object","properties":{"loc_origin":{"title":"loc_origin","type":"string","description":"The departure airport, e.g. DUS"},"loc_destination":{"title":"log_destination","type":"string","description":"The destination airport, e.g. HAM"}}}},"required":["loc_origin","loc_destination"]}] Use the following pydantic model json schema for each tool call you will make: {"properties": {"arguments": {"title": "Arguments", "type": "object"}, "name": {"title": "Name", "type": "string"}}, "required": ["arguments", "name"], "title": "FunctionCall", "type": "object"} For each function call return a json object with function name and arguments within <tool_call></tool_call> XML tags as follows:
<tool_call>
{"arguments": <args-dict>, "name": <function-name>}
</tool_call><|im_end|>
<|im_start|>user
When's the next flight from Amsterdam to New York?<|im_end|>
<|im_start|>assistant
<tool_call>
{"arguments": {"loc_origin":"AMS","loc_destination":"NYC"}, "name": "get_flight_info"}
</tool_call><|im_end|>
<|im_start|>tool
<tool_response>
ERROR: airport not found: 'NYC'
</tool_response>
<|im_end|>
<|im_start|>assistant
I could not find a flight from Amsterdam to New York. Please double-check the airport codes.<|im_end|>
<|im_start|>user
For the destination, I am referring specifically to the John F. Kennedy airport of New York<|im_end|>
<|im_start|>assistant
<tool_call>
{"arguments": {"loc_origin":"AMS","loc_destination":"JFK"}, "name": "get_flight_info"}
</tool_call><|im_end|>
<|im_start|>tool
<tool_response>
{"loc_origin": "AMS", "loc_destination": "JFK", "datetime": "2024-09-20 18:29:15.356063", "airline": "KLM", "flight_number": "KL 123"}
</tool_response>
<|im_end|>
<|im_start|>assistant
The next flight from Amsterdam to New York's John F. Kennedy airport is on KLM flight KL 123. It departs on September 20, 2024, at 18:29.<|im_end|>
<|im_start|>user
Ok, thank you very much<|im_end|>
<|im_start|>assistant

[mario7421]

@ngxson tagging you in case you don't have PR notifications enabled.