Tool upgrades in Moonlight Peaks are where a lot of early runs slow down. You start with the base axe, pickaxe, scythe, shovel, and watering can, but the game does not push you toward Ridge's upgrade menu very hard. The first real gate is A Bridge Too Far, because that opens Misty Shores and gives you access to the Cave of Echoes where your first upgrade ore comes from.
Once the bridge is open, go to Ridge's shop and open the upgrade tab. The first tier asks for coins, your current tool, and metal bars. Prima's launch guide lays out the pattern for the main tools: copper upgrades need 1,000 coins and 3 Copper Bars, iron upgrades need 4,000 coins and 3 Iron Bars, and gold upgrades need 16,000 coins and 3 Gold Bars. The choice that matters is not which tool feels nicest for one night. It is which upgrade gets you past the rocks that are holding back the next resource tier.
Pickaxe first is the safest route. Better pickaxes break larger rocks, open better ore nodes, and stop your whole upgrade path from stalling early. If you spend your first bars on the axe or watering can, one chore gets easier, but your next material jump usually comes later. After the pickaxe, move to the tool that is slowing your run the most.