Currently, there does not appear to be a way to place an upper or lower bound on an individual function within a function_score functions array. It would be nice to be able to place either a max or min limit on the individual function to prevent something like a field_value_factor from overshadowing other more relevant signals.

Example function_score:

"function_score": {
"query": {},
"boost": "boost for the whole query",
"functions": [
{
"filter": {},
"FUNCTION": {},
"weight": number,
"min_score": number // New Feature
},
{
"FUNCTION": {},
"max_score": number // New Feature
},
{
"filter": {},
"weight": number
}
],
"max_boost": number,
"score_mode": "(multiply|max|...)",
"boost_mode": "(multiply|replace|...)",
"min_score" : number
}