fix: missing model names in model cost litellm dict (#748)

Author: ds-sebastianchwilczynski

packages/ragbits-core/CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+- Fix issue with cost calculation for some models (#748)
 - Fix issue with improper convertion to json of tool call arguments (#737)
 - Added Google Drive support (#686)
 - Add LLM Usage to LLMResponseWithMetadata (#700)

packages/ragbits-core/src/ragbits/core/llms/litellm.py

@@ -116,7 +116,7 @@ def get_estimated_cost(self, prompt_tokens: int, completion_tokens: int) -> floa
         Returns:
             The estimated cost of the LLM call.
         """
-        response_cost = litellm.model_cost[self.model_name]
+        response_cost = litellm.get_model_info(self.model_name)
         response_cost_input = prompt_tokens * response_cost["input_cost_per_token"]
         response_cost_output = completion_tokens * response_cost["output_cost_per_token"]
         return response_cost_input + response_cost_output