Foursquare venue search (intent "browse") does not seem to honor categoryId

Question

if I make this query:

https://api.foursquare.com/v2/venues/search?categoryId=4e4c9077bd41f78e849722f9%2C4f4531084b9074f6e4fb0101%2C4bf58dd8d48988d1f7941735%2C4bf58dd8d48988d1fa941735%2C5032872391d4c4b30a586d64%2C4bf58dd8d48988d115951735%2C4bf58dd8d48988d1d3941735%2C4bf58dd8d48988d1ef941735%2C4bf58dd8d48988d116951735&client_id=DBYECJMGA0AB1XQP1GW5CV5WNXD4331IODMHARY5D3GSEOIB&intent=browse&limit=50&ne=43.802819%2C11.162109&sw=43.786958%2C11.140137&v=20131109&locale=en&client_secret=CLIENT_SECRET

in which I specify multiple category IDs, I get back this result:

{"meta":{"code":200},"response":{"venues":[{"id":"4f3ccf34e4b030292acf2336","name":"DI TUTTO DI PIU' - Mercatino usato","contact":{},"location":{"address":"Via Manderi, 62, 50013 Campi Bisenzio FI","lat":43.79576849102895,"lng":11.15417380610575,"postalCode":"50013","cc":"IT","city":"Campi Bisenzio","state":"Tuscany","country":"Italy"},"categories":[{"id":"4bf58dd8d48988d127951735","name":"Arts & Crafts Store","pluralName":"Arts & Crafts Stores","shortName":"Arts & Crafts","icon":{"prefix":"https://ss1.4sqi.net/img/categories_v2/shops/artstore_","suffix":".png"},"primary":true}],"verified":false,"restricted":true,"stats":{"checkinsCount":16,"usersCount":15,"tipCount":2},"specials":{"count":0,"items":[]},"hereNow":{"count":0,"groups":[]},"referralId":"v-1392811869"}]}}

which contains a venue whose categoryId is 4bf58dd8d48988d127951735 ("Arts & Crafts Store"), which is not included in the request.

Answer 1

The compact venue result that you posted is only showing the primary category of the venue, which is an arts and crafts store. However, if you run a venue details call with that venue ID, you're able to see that the venue has a secondary category ID of flea market, which you searched for. The search matches on both primary and secondary category IDs