[Python] How to customize Pydantic validation error messages to exclude "Value error" prefix?

The below code consists of a company model and I have put up a validation for a blank company name. I am considering raising a custom validation error message but the error message has the prefix Value error, which I do not want. How can I get rid of it?

Python Code:

from datetime import date
from typing import Optional

from pydantic import (
BaseModel,
field_validator,
HttpUrl,
EmailStr
)
from pydantic import ValidationError


class Company(BaseModel):
company_id: Optional[int] = None
company_name: Optional[str]
address: Optional[str]
state: Optional[str]
country: Optional[str]
postal_code: Optional[str]
phone_number: Optional[str]
email: Optional[EmailStr] = None
website_url: Optional[HttpUrl] = None
cin: Optional[str]
gst_in: Optional[str] = None
incorporation_date: Optional[date]
reporting_currency: Optional[str]
fy_start_date: Optional[date]
logo: Optional[str] = None

@field_validator('company_name')
def validate_company_name(cls, v):
if v is None or not v.strip():
raise ValueError("Company name must be provided.") # Custom Error Message
return v

payload = {
"company_name": None,
"address": "DLH Park, Mumbai",
"state": "Maharashtra",
"country": "India",
"postal_code": "400066",
"phone_number": "+9122380199",
"email": "info@mailto.com",
"cin": "U45678TX2023PTC111222",
"incorporation_date": "2015-07-20",
"reporting_currency": "INR",
"fy_start_date": "2010-04-01"
}

try:
company = Company(**payload)
print("✅ Valid payload:", company.model_dump())
except ValidationError as e:
print("❌", e.errors()[0]['msg'])


Output:

❌ Value error, Company name must be provided.


Desired Output:

❌ Company name must be provided.


Complete error message produced by pydantic validation:

[
{
'type': 'value_error',
'loc': ('company_name',),
'msg': 'Value error, Company name must be provided.',
'input': None,
'ctx': {
'error': ValueError('Company name must be provided.')
},
'url': 'https://errors.pydantic.dev/2.10/v/value_error'
}
]


Note: I know the workarounds by using str.replace() or raising a custom exception instead of ValueError. Can we do something else?

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