If the test is open ended like "implement a simple API and a client that accesses it" then it's a terrible test. Tests that are better the more time you put into it are always terrible take home tests.
If it has well-defined success state then it's maybe OK "implement a maze-solving algorithm for a 3^n cube". If there are implementation tests that the candidate can use, even better
If it has well-defined success state then it's maybe OK "implement a maze-solving algorithm for a 3^n cube". If there are implementation tests that the candidate can use, even better