callables_protocol error

Callable call-site arity and argument validation

When a parameter is annotated as Callable[int, str, T], calls to that parameter must match the expected argument count. Additionally, Callable parameters are implicitly positional-only, so keyword arguments are not allowed.

How to handle it

Every rule is on by default — strict is the default, not a cage. You can dial callables_protocol down per-file or per-path from your editor or pyproject.toml, or fix the code so it type-checks. See the Type System rules and the complete diagnostic reference.

Canonical URL: https://www.basilisk-python.dev/errors/callables_protocol