Metrics memory.committedHeap and memory.usedHeap do not have description

curl -H "Accept: application/json" -X OPTIONS http://localhost:9990/metrics/base/memory.usedHeap

{
    "memory.usedHeap": {
        "unit": "bytes",
        "type": "gauge",
        "displayName": "memory.usedHeap",
        "tags": ""
    }
} 

curl -H "Accept: application/json" -X OPTIONS http://localhost:9990/metrics/base/memory.committedHeap

{
    "memory.committedHeap": {
        "unit": "bytes",
        "type": "gauge",
        "displayName": "memory.committedHeap",
        "tags": ""
    }
}