'AIMessage' object has no attribute 'content_blocks'

Hello,

I have a installed

Name: langchain Version: 1.0.0a3

Name: langchain-core Version: 1.0.0a2

and using OSS(V1-alpha) docs: Streaming - Docs by LangChain

for this code

for chunk in agent.stream(

{“messages”:[{“role”:“user”,“content”:“What is the weather in London”}]},

stream_mode=“updates”,

):

for step, data in chunk.items():

    print(f"step:{step}")

    print(f"content:{data\["messages"\]\[-1\].content_blocks}")

--------------------------------------------------------------------------- AttributeError Traceback (most recent call last) Cell In[33], line 7 5 for step, data in chunk.items(): 6 print(f"step:{step}“) ----> 7 print(f"content:{data[“messages”][-1].content_blocks}”) File c:\GitHub\langchainLearningPlayground\langchainlearningvenv\Lib\site-packages\pydantic\main.py:992, in BaseModel._getattr_(self, item) 989 return super()._getattribute_(item) # Raises AttributeError if appropriate 990 else: 991 # this is the current error → [992](file:///C:/Users/riahl/OneDrive/UKCareer/Careers/Resume/Companies/PrynGlobal/FoundationsMVPBuild/GitHub/langchainLearningPlayground/langchainlearningvenv/Lib/site-packages/pydantic/main.py:992) raise AttributeError(f’{type(self)._name_!r} object has no attribute {item!r}') AttributeError: ‘AIMessage’ object has no attribute ‘content_blocks’

but it works with .content

Appreciate your help to fix this error

Hi @RiyazPrynAI, could you please upgrade to the latest alpha (langchain 1.0.0a4) and ensure you are using either langchain-openai 1.0.0a2 or langchain-anthropic 1.0.0a1?

Things are working on my end.