gpt-5.3-codex: Running into error "Unknown parameter: 'input[6].phase'."

I am using the recent gpt-5.3-codex model and kept running into this error:

{
  "error": {
    "message": "Unknown parameter:
'input[6].phase'.",
    "type":
"invalid_request_error",
    "param": "input[6].phase",
    "code": "unknown_parameter"
  }
}

You can see it in this error in these two threads:

• 019c3057-c977-74b0-8e6e-4922dcba1115
• 019c304f-2485-7c40-8835-aaf22564eab5