Once a year, with a shorter fuse than most snakes
A healthy adult green tree python should have a routine reptile vet check once a year, and keepers of this species should hold a lower threshold for extra visits than they would for a hardier snake. Green tree pythons are arboreal display animals from humid forests, exquisitely responsive to their microclimate and notably less forgiving of husbandry drift than a corn snake or king snake. The annual wellness visit, weight, breathing, mouth, skin, and condition assessed as the snake rests in its characteristic saddle coil on a perch, is the scheduled safeguard. Between those visits, this species' keepers treat change as information to act on, not to file away.
The first visit waits for the snake to settle and feed
Timing the initial check takes judgement with a green tree python. A newly arrived snake should be allowed to settle, establish its perch routine, and feed before a non-urgent examination adds its stress, unless something is visibly wrong on arrival. At that first appointment the vet will assess body condition and hydration, examine the mouth and breathing, inspect the skin and tail, and review the enclosure's perches, humidity cycle, and temperature gradient in the detail this species demands. A parasite screen from a dropping is a common part of a first workup. The goal is a baseline taken from a snake behaving like itself, against which every later year can be honestly compared.
Humidity-linked problems set the extra-visit agenda
The concerns that should bring a green tree python in between annual checks follow its biology. Wheezing, mucus, or a snake resting with its head raised and mouth slightly open points to respiratory trouble in a humid enclosure and deserves prompt attention. Retained, patchy sheds in a snake whose humidity cycle has not changed, repeated soaking it would not normally choose, swelling, or a kink or weakness along the spine all justify appointments. So does a feeding change: this species can be a deliberate, perch-bound hunter, but a settled snake that abandons a reliable feeding routine while losing the fullness along its back is presenting a trend, and trends in a sensitive snake are vet business.
What the annual examination can and cannot see
Expect the vet to weigh the snake, judge muscle and hydration, examine the mouth, eyes, skin, vent, and tail, and listen for any respiratory sound, all with handling kept as calm and brief as the snake allows, since many green tree pythons are defensive and stress visibly. The examination's other half is your data: perch-level temperatures, the misting and humidity pattern, spray-water routine, feeding dates and prey, and shed dates and completeness. A green tree python's body is a readout of its climate, and a vet given only the snake, without the climate record, is being asked to diagnose with half the evidence missing.
Climate records belong with the clinical ones
Keep the environmental log and the veterinary history in one continuous record: annual weights and findings beside the temperatures and humidity the snake actually lived in, the prey it accepted, and the quality of each shed. When a problem appears, that combined file usually shows when the drift began. Maintaining it is straightforward with KinsLe Pet Passport, which keeps this python's vet notes and husbandry records together in a single portable packet.