Pydantic Migration Guides
Fix simple Pydantic validator migrations and keep signature-heavy cases out of the automatic path.
Start here
If the validator uses the supported direct-import path and the simple classmethod signature, the clean rewrite is @field_validator.
Stop before automation when: Validators that use values, field, config, each_item, or always. Alias-heavy imports.
from pydantic import BaseModel, field_validator
class UserModel(BaseModel):
email: str
@field_validator("email")
def normalize_email(cls, value: str) -> str:
return value.strip().lower()
Repo fit check
Run the matching scanner locally first. Read the free findings and manual alternatives; consider paid cleanup only if supported patterns repeat enough to justify the price.
Example scan summary
supported_findings: 38
manual_review_findings: 6
files_uploaded: 0
confidence: reviewableWhy this page exists
Direct imports and simple validator signatures are good automation targets. The rest should stop cleanly.
Direct answer
If the validator uses the supported direct-import path and the simple classmethod signature, the clean rewrite is @field_validator.
Example
from pydantic import BaseModel, validator
class UserModel(BaseModel):
email: str
@validator("email")
def normalize_email(cls, value: str) -> str:
return value.strip().lower()
from pydantic import BaseModel, field_validator
class UserModel(BaseModel):
email: str
@field_validator("email")
def normalize_email(cls, value: str) -> str:
return value.strip().lower()
Decision path
The cleanup pack is strongest when the repo still uses direct pydantic imports and a clean validator/settings/config subset.
Before checkout
Price: $249.99 per team.
Use the exact-problem guides as a triage layer, then decide whether the repo is inside the supported subset.
FAQ
If the validator uses the supported direct-import path and the simple classmethod signature, the clean rewrite is @field_validator.
Automate only the supported subset: Direct validator to field_validator rewrites. Repo reporting for supported files. Links to related Pydantic guides. Keep these cases in manual review: Validators that use values, field, config, each_item, or always. Alias-heavy imports. Decorator wrappers and meta-programming.
Use Pydantic v1 to v2 Migration Cleanup Pack only when this pattern repeats across enough files that manual cleanup is still costly. Use the free report and upstream guide to evaluate fit. Buy only if repeated supported edits justify the price; no paid assessment is required.
Purchase fit
One matching page is not enough by itself. Run the local scan, then buy only when the same supported pattern appears often enough to matter.
Move BaseSettings to pydantic-settings, Convert Config to model_config, Replace validate_arguments with validate_call, Replace @root_validator(pre=True) with @model_validator(mode="before"), Why post root validators need manual review, Move pydantic.v1 imports onto pydantic, Why Config.fields is a manual-review case, Why @validator(each_item=True) needs manual review