There is a total of 7 tools in Harvest Moon Light Of Hope, of which 5 of these can be upgraded. It is highly recommended for the player to upgrade their tools because not only will you consume less stamina on using them, you will unlock various effects such as covering more area, or removing obstacles. Once you upgrade a tool, the next upgrade will become available.
Unlocking Tool Upgrades
To unlock Gus's Smithy, you must first repair the Smithy. The next day, Gus's granddaughter Melanie will show up and give you a Hammer. Gus will request that you mine him some Iron Ore before he will move back into his Smithy, which will require you to repair the Mines and smash up some rocks. After doing so, Gus will provide his services to you. You can have him upgrade your tools, or simply refine ores. Gus's Smithy is open from 6 AM - 6 PM every day except Sunday.