"a character proficient with carpenter's tools can apply his or her proficiency bonus to a Dexterity check to craft a wooden flute, an Intelligence check to craft a wooden secret door, or a Strength check to build a working trebuchet. However, the proficiency bonus wouldn't apply to an ability check made to identify unsafe wooden construction or to discern the origin of a crafted item, since neither check requires tool use."
So according to DMG, you can only add your proficiency bonus from the tools if you are actually using the tools to work or craft a specific thing.
But then in Xanathar’s Guide to Everyhing, the Tool Descriptions (p. 78) states (emphasis mine):
"Skills. Every tool potentially provides advantage on a check when used in conjunction with certain skills, provided a character is proficient with the tool and the skill"
For example, for Smith's Tools we read:
"Arcana and History. Your expertise lends you additional insight when examining metal objects, such as weapons"
Therefore, while the DMG focuses on proficiency bonuses being applied to crafting or building tasks, XGE extends this concept by suggesting the potential for advantage on checks involving tools and associated skills.
I know XGE came after the DMG, but considering that the DMG had several errata (even in 2021), perhaps updating that part of the DMG in a future edition of the books, if XGE offers better utility, would be good.
This is more of a thought than a question, really. Ultimately, the rules from the Dungeon Master prevail!
DMG is core rules and XGE is optional rules, that brought in the context of tools a way to improve the benefit of being proficient both in a skill and a tool used in a task.
In the DMG (p. 239), it's stated (emphasis mine):
So according to DMG, you can only add your proficiency bonus from the tools if you are actually using the tools to work or craft a specific thing.
But then in Xanathar’s Guide to Everyhing, the Tool Descriptions (p. 78) states (emphasis mine):
For example, for Smith's Tools we read:
Therefore, while the DMG focuses on proficiency bonuses being applied to crafting or building tasks, XGE extends this concept by suggesting the potential for advantage on checks involving tools and associated skills.
I know XGE came after the DMG, but considering that the DMG had several errata (even in 2021), perhaps updating that part of the DMG in a future edition of the books, if XGE offers better utility, would be good.
This is more of a thought than a question, really. Ultimately, the rules from the Dungeon Master prevail!
DMG is core rules and XGE is optional rules, that brought in the context of tools a way to improve the benefit of being proficient both in a skill and a tool used in a task.
Basically they decided the DMG interpretation had proved to be too narrow, and so XGtE added optional material broadening the scope.
Thanks for the answers, guys. You gave me the context I needed.