observability-tracing-callback-con-langfuse-logs-warning-langfuse-was-not-able-to-par-8f933e62

THEN Ensure the Langfuse callback handler is added to both the LLM's callbacks list and the chain's config callbacks. Verify version compatibility: if using langchain-core>=0.1.46, langchain-community>=0.0.34, consider downgrading to langchain-core==0.1.39, langchain-community==0.0.31, or updating the langfuse package to a version that supports the new LangChain model representation. Also confirm that model_id is passed correctly and not overridden by model_kwargs.

langfuse_handler = CallbackHandler(secret_key='...', public_key='...', host='...')
llm = BedrockChat(model_id='...', callbacks=[langfuse_handler])
chain = prompt_template | llm | output_parser
chain.invoke(input={'color': 'red'}, config={'callbacks': [langfuse_handler]})