GPT 5.5 become stupid to a unacceptable level

What version of Codex CLI is running?

v0.130.0

What subscription do you have?

Plus

Which model were you using?

gpt-5.5

What platform is your computer?

_No response_

What terminal emulator and version are you using (if applicable)?

_No response_

What issue are you seeing?

I wrote a tool for my agent, and inside that tool, I left a main function without implementing it, just filling it with pass. Then I said I wanted to see its result, and it actually went ahead and ran that function. What I meant was for it to complete the main function.

Then I saw that the input was written in JSON, so I asked why use JSON instead of pydantic? It interpreted that as meaning the output should also be written using pydantic.

In another conversation, it made error handling extremely complicated, identifying an error code for every single error. I really don't understand what it was thinking.

What steps can reproduce the bug?

Uploaded thread: 019e10da-a691-7ae3-b91a-3b3dd5230136

What is the expected behavior?

_No response_

Additional information

_No response_