How to use opencode with Fabapp AI
Connecting opencode to your account
opencode declares MCP servers in opencode.json, marking this one as running locally:
{ "mcp": { "fabapp": { "type": "local", "command": ["npx", "-y", "@fabappai/cli", "mcp"] } } }
The command is the same as in any client; what changes is the shape, which here takes the command as a list and asks for the server's type. If your version arranges it differently, opencode's documentation is what counts.
What you need
Node 20 or newer, a Fabapp account on the Builder plan or above, and a single login:
npx @fabappai/cli login
The credential goes into the system keychain. It is never displayed, and it is revoked from one place, in the panel.
The loop
npx @fabappai/cli create "My store"
npx @fabappai/cli dev
dev assembles the app on your machine on the same template the platform publishes with, installs the dependencies
and starts the local server. With it running, ask for what you would do by hand: read the definition, create the
entities, write the screens. Then:
npx @fabappai/cli deploy
It uploads what you changed and publishes, in that order. Publishing before uploading would publish what is on the server, and your work would be left behind.
What is different about opencode
opencode is open and does not tie you to one model provider. That is why most people pick it, and it has a good consequence on the Fabapp side: the model cost is yours and so is the choice. You can run the whole loop on whatever model you prefer, including a local one, and the platform is not part of that bill.
What it does not change is worth saying: the tools the assistant receives are the same, because what exists is decided by the credential's permission, not by the client or the model. A weaker model does not get more tools or fewer; it just uses the ones it has less well.
What to ask for
"Read the platform documentation before writing the schema." The field types are a closed list and anything else is refused; the access rules are the only thing between an app's data and the public.
"Read the current definition before changing it." Without the schema at hand, a wrong model id answers 404 and an invented field answers 422.
"Schema first, screens after." The SDK is generated against the data model.