codex has an option to expose itself as an MCP. You can also use something like OpenCodex to bring Anthropic models into Codex as any other selectable model.
The reason I did it the way I did was so that I can still use the codex and claude code subscriptions vs paying the API cost. Can you do that via OpenCode?
I'm using OpenCodex as a backend provider with Codex as the front-end, with the $200/mo ChatGPT subscription. Not OpenCode!