src/sys/examples/topology/meta/echo_client.cml

// Component manifest for the `echo_client` example program, which sends a message to the Echo
// service.
{
    "program": {
        "binary": "bin/echo_client",
    },
    "use": [
        {
            "service": "/svc/fidl.examples.topology.echo.Echo",
        },
    ],
}