Purpose of Molotov visit was to establish what the hell Germany wants, since historically there were some demands brought forward by the aggressor, before attack ensued.
False. The purpose of the Molotov visit was to present Soviet demands for further westward expansion into Europe.
Molotov asked that the Soviet Union be allowed to invade Finland again, to set up bases in Bulgaria (ie bring Bulgaria under its control, thereby strangling Romania, Germany's only source of oil other than the Soviet Union), and to set up bases on the Bosphorus, thereby bringing the exit from the Black Sea under its control. All of these demands were of immense strategic importance, and it granted would have given the Soviet Union domination of Eastern Europe.
The above were the conditions that the Soviet Union set for joining in an alliance with Germany, Italy and Japan.
Germany had asked the Soviet Union to join that alliance, but suggested that the Soviet Union should expand southward, toward Iran and India, rather than further westward into Europe. The Soviet reply was that it wanted to expand into Turkey and Iran, but insisted on westward expansion as well.
Germany was determined to prevent any further westward expansion of the Soviet Union, beyond the Baltic States, Eastern Poland and Eastern Romania. At the November talks in Berlin, and in the subsequent letter from Stalin, the Soviet Union made it clear that it would insist on further westward expansion. It was after the receipt of the letter from Stalin, setting his terms for joining in an alliance with Germany, that Hitler made his final decision for a preventive attack on the Soviet Union.