Census site provides a geocoding service named TIGERWeb. I was able to deduce both Metropolitan and Micropolitan Statistical Areas from geocoordinates. Here are a couple of examples:
https://geocoding.geo.census.gov/geocoder/geographies/coordinates?y=29.7119708&x=-95.4945362&benchmark=Public_AR_Current&vintage=ACS2019_Current&layers=80,82&format=json
This point is inside Houston MSA. The response is:
{
"result": {
"input": {
"benchmark": {
"id": "4",
"benchmarkName": "Public_AR_Current",
"benchmarkDescription": "Public Address Ranges - Current Benchmark",
"isDefault": false
},
"vintage": {
"id": "419",
"vintageName": "ACS2019_Current",
"vintageDescription": "ACS2019 Vintage - Current Benchmark",
"isDefault": false
},
"location": {
"x": -95.4945362,
"y": 29.7119708
}
},
"geographies": {
"Metropolitan Statistical Areas": [
{
"GEOID": "26420",
"CENTLAT": "+29.7493821",
"AREAWATER": 3046140233,
"BASENAME": "Houston-The Woodlands-Sugar Land, TX",
"OID": 2625913782255639,
"LSADC": "M1",
"FUNCSTAT": "S",
"INTPTLAT": "+29.7495926",
"NAME": "Houston-The Woodlands-Sugar Land, TX Metro Area",
"CSA": "288",
"OBJECTID": 767,
"CENTLON": "-095.3538987",
"CBSA": "26420",
"AREALAND": 21413280815,
"INTPTLON": "-095.3536422",
"MTFCC": "G3110"
}
],
"Micropolitan Statistical Areas": [
]
}
}
}
https://geocoding.geo.census.gov/geocoder/geographies/coordinates?y=29.1989794&x=-96.2875396&benchmark=Public_AR_Current&vintage=ACS2019_Current&layers=80,82&format=json
Thise other point is outside Houston MSA (and I've selected it purposely to not be inside another MSA):
{
"result": {
"input": {
"benchmark": {
"id": "4",
"benchmarkName": "Public_AR_Current",
"benchmarkDescription": "Public Address Ranges - Current Benchmark",
"isDefault": false
},
"vintage": {
"id": "419",
"vintageName": "ACS2019_Current",
"vintageDescription": "ACS2019 Vintage - Current Benchmark",
"isDefault": false
},
"location": {
"x": -96.2875396,
"y": 29.1989794
}
},
"geographies": {
"Metropolitan Statistical Areas": [
],
"Micropolitan Statistical Areas": [
{
"GEOID": "20900",
"CENTLAT": "+29.2777605",
"AREAWATER": 21287757,
"BASENAME": "El Campo, TX",
"OID": 2625913782255505,
"LSADC": "M2",
"FUNCSTAT": "S",
"INTPTLAT": "+29.2784805",
"NAME": "El Campo, TX Micro Area",
"CSA": "288",
"OBJECTID": 674,
"CENTLON": "-096.2222023",
"CBSA": "20900",
"AREALAND": 2813117310,
"INTPTLON": "-096.2296745",
"MTFCC": "G3110"
}
]
}
}
}
As you might notice on both responses, the former one includes valid data on the section "Metropolitan Statistical Areas" but not on "Micropolitan Statistical Areas", and viceversa for the second one.