This morning, I was fixing a bug in the front-end chart rendering. Claude Code struggled for a while but still couldn’t solve it. Later, I asked Codex to analyze the root cause, and it was fixed in no time. If your Claude Code hasn’t installed Codex MCP yet, I strongly recommend installing it. The default model is set to GPT 5.2 with high reasoning, and it can help you figure out many unsolvable bugs and unclear specs.