[Python] No model seems to support supports_parallel_function_calling to LiteLLM

I'm using LiteLLM in a Python project and I'm testing support for parallel function calling on different models.
Here’s a minimal reproducible example:

from litellm import completion
from litellm.utils import supports_function_calling, supports_parallel_function_calling

models = [
"openai/gpt-5",
"openai/gpt-5-mini",
"openai/gpt-4-turbo-preview",
"openai/gpt-4o",
]

for model in models:
print(f"Model: {model}")
print(" Supports function calling:", supports_function_calling(model))
print(" Supports parallel function calling:", supports_parallel_function_calling(model))
print()


Output I get:

Model: openai/gpt-5
Supports function calling: True
Supports parallel function calling: False

Model: openai/gpt-5-mini
Supports function calling: True
Supports parallel function calling: False

Model: openai/gpt-4-turbo-preview
Supports function calling: True
Supports parallel function calling: False

Model: openai/gpt-4o
Supports function calling: True
Supports parallel function calling: False


According to the [official LiteLLM docs (https://docs.litellm.ai/docs/completion/function_call), you can do:

assert litellm.supports_parallel_function_calling(model="gpt-4-turbo-preview") == True


So I expected supports_parallel_function_calling("gpt-4-turbo-preview") to return True, but in my test it always returns False.

LiteLLM version : 1.76.0

Edit: the problem does not come from the name of the model in my code like chatgpt-4 instead of openai/chatgpt-4. Moreover in the official doc it often talks about gpt-3.5-turbo-1106 but that doesn't work for me either

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