I have been testing agentic coding with Claude 4.5 Opus and the problem is that it's too good at documentation and test cases. It's thorough in a way that it goes out of scope, so I have to edit it down to increase the signal-to-noise.
1. Take every single function, even private ones.
2. Mock every argument and collaborator.
3. Call the function.
4. Assert the mocks were called in the expected way.
“Mock the world then test your mocks”, I’m simply not convinced these have any value at all after my nearly two decades of doing this professionally