Issue with Pydantic

[hwchase17]

1/ a graph state key is a Pydantic model
class Analyst(BaseModel):
description: str = Field(
2/ i edit it in Studio
3/ edited state is no long a Pydantic model (converted to dict after edit in Studio, IIUC)
4/ anything in code that assumes Pydantic model will then break w/ the edited state
e.g., accessing one attribute -
analyst.description
error -
AttributeError: 'dict' object has no attribute 'description'

[dqbd]

@nfcampos Seems like a LangGraph issue? Don't think Studio does anything else here differently?

[oleksandr-lytvynenko]

got similar issue

Here's my agent state class

Did the setup right as described at https://langchain-ai.github.io/langgraph/how-tos/state-model/#how-to-use-pydantic-model-as-state

Here's the error I'm getting

When launching w/o LangGraph Studio, it works OK

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The issue is very likely roots in using Pydantic for agent state.
I checked it by returning to using TypedDict for agent state and this worked in Langgrapg Studio

[khyaalnix]

Is there any update on using pydantic model for state ? Facing a similar issue as @oleksandr-lytvynenko.