dict-type-inconsistency
Dict return type annotation doesn't match actual value types being assigned.
Applies to: Python
Why this matters
When a function claims to return Dict[str, str] but assigns untyped values from iterating over a Dict[str, Any] input, type checkers trust the annotation and won't catch runtime errors. This bug surfaces far from where the problem is - often when Pydantic/FastAPI validate at runtime. Use consistent types or validate/convert values.
Catch it before it ships
pip install stablestack # or: npx stablestackstablestack # scans your project, TYPE006 includedstablestack explain TYPE006TYPE006 is part of the Pro rule set. See pricing — the free tier ships 24 checks with no signup.
False positive in your codebase? Suppress a single line with # noqa: TYPE006
More Type Safety checks
weak-typing
Weak typing pattern (Dict[str, Any], List[Any]) loses type safety.
TYPE002naked-dict-for-structured-data
Using plain dict for structured data instead of dataclass/TypedDict.
TYPE004missing-type-hints
Function is missing type hints.
TYPE005inline-type-definition
Inline type definition instead of using shared/generated types.
TYPE007duplicate-type-definition
Type definition may be duplicated across files.
TYPE008typescript-any
Explicit 'any' type defeats TypeScript's type safety
TYPE009env-non-null-assertion
Non-null assertion on env vars can cause runtime crashes
TYPE010unsafe-json-parse
JSON parsing with type assertion lacks runtime validation