Passing field descriptions to graphiql documentation

I'm trying to pass a description from one of the pydantic fields to the graphiQL documentation. I can't seem to get it to be recognized. It seems to be supported in graphene directly on the fields like this:
``` python
class Person(ObjectType):
first_name = graphene.String(required=True)
last_name = graphene.Field(String, description='Surname')
```

In pydantic it's supported like this:
```python
class MainModel(BaseModel):
"""
This is the description of the main model
"""
snap: int = Field(
42,
title='The Snap',
description='this is the value of snap',
gt=30,
lt=50,
)
```

I've implemented the pydantic style description and don't see any change to the GraphiQL documentation on that field. Any ideas how to pass it over, or is this simply not supported with this library? I'm following the excellent tutorial here: https://testdriven.io/blog/fastapi-graphql/ but they don't spend any time on the self-documenting nature of graphql which is something really enjoy.

Thanks!