Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

Tried opencode with zed + ACP and found that / commands are not supported yet.

The /help command is not supported by opencode.

Available commands: none

I try to use spec-kit with it, which requires custom / commands. With claude-code this thing is magic, but I try to use the planning phase with gpt-5 pro on this project via opencode.