How should stirring mechanism be evaluated when buying an automatic cooking machine?

First have the supplier identify the stirring type — planetary paddle, drum, swing arm or wall-scraper — then design tests around that geometry. Cook large meat chunks to check even tumbling without tearing, leafy greens to measure breakage and water release, and rice grains to gauge pan residue and sticking. Run each batch at the same wok temperature, speed and load, logging cook time, broken-particle ratio and residue area on the wok wall. Automatic tossing does not mean every design handles soft or crisp items, so set acceptance limits from these trials rather than catalogue figures.