Credence.Rule.DescriptiveNames (credence v0.2.0)

Maintainability rule: Flags single-letter variable names in function signatures.

Using names like a, b, or n makes the code harder to reason about. Replacing them with descriptive names like index, accumulator, or previous_value improves readability and reduces cognitive load.

Bad

def process(a, b), do: a + b

Good

def process(base_value, increment), do: base_value + increment