It's already available, but given the lack of documentation I understand it's hard to find. We refer to the sgminer 5.5 API docs, but those are somewhat confusing as well... Anyway, the "devdetails" command is what you want. For a single gpu, this is what you get, the "Kernel" field contains the algo:
$ echo '{"command": "devdetails"}' | nc localhost 4028 | python -m json.tool
{
"DEVDETAILS": [
{
"DEVDETAILS": 0,
"Device Path": "05:00:0",
"Driver": "opencl",
"ID": 0,
"Kernel": "cn_conceal",
"Model": "Radeon RX 570 Series",
"Name": "GPU"
}
],
"STATUS": [
{
"Code": 69,
"Description": "TeamRedMiner 0.5.7.1",
"Msg": "Device Details",
"STATUS": "S",
"When": 1566223785
}
],
"id": 1
}