Summary
Since switching to GPT-5.6 in Codex, I have experienced a noticeable decline in day-to-day coding quality together with apparently higher token consumption.
Observed behavior
- The agent more often repeats questions or loses track of information already provided in the thread.
- Small, targeted tasks sometimes trigger broader repository exploration or unrelated refactoring.
- It spends more time explaining or exploring alternatives instead of making a precise minimal patch.
- Cross-file understanding and continuity across turns feel less reliable.
- Fixes can introduce new issues, reducing confidence in allowing the agent to modify code autonomously.
- For comparable tasks, usage appears to consume more tokens than before, without a corresponding improvement in correctness or stability.
Expected behavior
- Preserve relevant context reliably across turns.
- Prefer the smallest necessary change and avoid unrelated edits.
- Limit repository scans and repeated test runs when the task is narrow.
- Use token budget efficiently and provide predictable quality for comparable tasks.
- Make token usage more transparent, ideally broken down by repository reads, reasoning, tool calls, and generated output.
Additional note
This is primarily experiential feedback rather than a controlled benchmark. The key issue is the combination of higher perceived cost and lower confidence in the resulting code. It would be helpful if the team could compare GPT-5.6 against prior Codex models on long-thread continuity, minimal-patch behavior, unnecessary file reads, repeated tool calls, and total token usage per completed task.
Summary
Since switching to GPT-5.6 in Codex, I have experienced a noticeable decline in day-to-day coding quality together with apparently higher token consumption.
Observed behavior
Expected behavior
Additional note
This is primarily experiential feedback rather than a controlled benchmark. The key issue is the combination of higher perceived cost and lower confidence in the resulting code. It would be helpful if the team could compare GPT-5.6 against prior Codex models on long-thread continuity, minimal-patch behavior, unnecessary file reads, repeated tool calls, and total token usage per completed task.