  "mempoolminfee": 0.00000000

When the minrelaytxfee is > 0.

{
    UniValue rv(UniValue::VOBJ);
    rv.push_back(Pair("id", name));
    rv.push_back(Pair("version", version));
    rv.push_back(Pair("reject", SoftForkMajorityDesc(version, pindex, consensusParams)));
    return rv;
}
static UniValue BIP9SoftForkDesc(const Consensus::Params& consensusParams, Consensus::DeploymentPos id)
{
    UniValue rv(UniValue::VOBJ);
    const ThresholdState thresholdState = VersionBitsTipState(consensusParams, id);
    switch (thresholdState) {
    case THRESHOLD_DEFINED: rv.push_back(Pair("status", "defined")); break;
    case THRESHOLD_STARTED: rv.push_back(Pair("status", "started")); break;
    case THRESHOLD_LOCKED_IN: rv.push_back(Pair("status", "locked_in")); break;
    case THRESHOLD_ACTIVE: rv.push_back(Pair("status", "active")); break;
    case THRESHOLD_FAILED: rv.push_back(Pair("status", "failed")); break;