Use the map before assuming Tyler zoning applies

Plenty of houses that get their mail in Tyler sit well outside it, on unincorporated land that belongs to Smith County. The mailing address tells you nothing. The city limit line does, and it's the line that decides whether Tyler's zoning, setbacks, and permit rules reach your parcel or stop short of it. Pull up the address on SmithCountyMapSite.org and you'll see which side you're standing on.

From there everything keys off the zoning classification. Setbacks and what you're allowed to do with the land both follow it, and you can trace your parcel's class through that same mapping site and the city's Unified Development Code tables.

The difference shows up the moment you do something physical: buy a piece of land, drop a shed or an accessory building, run a business out of the house, set a fence post. Inside Tyler, that puts you on the city's zoning and permit track. Outside it, you answer to Smith County's unincorporated-area rules instead, plus any utility easement or subdivision restriction that came stapled to the parcel.