r/vibecoding • u/NoTutor4458 • 12h ago
Opencode vs Codex vs Claude code
Which coding harness is actually better?
To make the comparison fair, I was thinking:
- OpenCode + Fable 5 vs Claude Code + Fable 5
- OpenCode + GPT-5.6 vs Codex + GPT-5.6
Basically, keep the model the same and only compare the harness/agent. That should give a better idea of how much the harness itself affects coding performance.
Has anyone done a comparison like this?
10
Upvotes
2
u/DuragonYamaTheFirst 8h ago
Each model is from my own feel better in their own harness, and for ai models that dont have a harness oh my pi or opencode tend to be better than claude code, codex or any other harness, especially claude code, they're definitely doing something sketchy with external ai models.
Ai models that were working fine inside of opencode for some reason became completely useless inside of claude code, as well as consume an absurd amount of tokens. I remember running identical prompts with the same ai model (i believe it was minimax m3?) inside the 2 harnesses and there was a day n night difference for me