Palmyra X5 raises not implemented error when trying to call using ChatBedrock

[MatheusAbdias]

llm = ChatBedrock(
    model="us.writer.palmyra-x5-v1:0",
    temperature=0.5,
    max_tokens=1000,
)

response = llm.invoke("Test")

# exception
ChatPromptAdapter.convert_messages_to_prompt(cls, provider, messages, model)
    526     prompt = convert_messages_to_prompt_anthropic(
    527         messages=messages,
    528         human_prompt="\n\nUser:",
    529         ai_prompt="\n\nBot:",
    530     )
    531 else:
--> 532     raise NotImplementedError(
    533         f"Provider {provider} model does not support chat."
    534     )
    535 return prompt

NotImplementedError: Provider writer model does not support chat.

Packages Versions

langchain 0.3.25
langchain-aws 0.2.22
langchain-community 0.3.23
langchain-core 0.3.58

[AlcebiadesFilho]

We need Palmyra X5

[michaelnchin]

Thanks for submitting this issue, @MatheusAbdias - we are looking into updating ChatBedrock for Palmyra model support.

In the meantime, would you be open to using ChatBedrockConverse instead? This chat model already supports Palmyra invocations (with streaming support coming in the next release).

More broadly, ChatBedrockConverse uses Bedrock's new Converse API. Unlike ChatBedrock's Invoke API, this provides model-agnostic I/O handling, and is therefore far more resilient to changing requirements for future models.