litellm/langfuse observability

[almex-m-bulbul]

Trying to log my input/output along with tag, metadata etc. Couldn't find any information on that.

Did a bit hack as usual litellm.success_callback = ["langfuse"] didn't work.

import litellm
litellm.success_callback.extend(["langfuse"])
litellm.failure_callback.extend(["langfuse"])

which can log input/output. But unable to log additional information.
tried adding metadata in llm_generation_chain, didn't work.

llm_generation_chain(
            template_file=template_file,
            engine=self.model,
            max_tokens=max_tokens,
            temperature=temperature,
        ).ainvoke(variables, config={"metadata": {"language": language, ....}})

Any suggestions?