Detective's Notebook (Patreon)

Wondrous item, uncommon (requires attunement)

This worn notebook is filled with pages of scribbled notes, addendums, and sketches—many of which seem to be added by different sources. While holding the book, whenever you make an Intelligence (Investigation) or Wisdom (Insight) check, you gain a +1 bonus to the roll. If you spend at least 10 minutes investigating or interacting with the subject of these checks while writing notes in the book, you make the roll with advantage.

In addition, you can use an action to cast the comprehend languages, detect thoughts, or locate object spell from the book (save DC 13). Once the book has been used to cast one of these spells, it shouldn't be used to cast a spell again in this way until the next dawn. Each time it is used again before then, the book has a cumulative 20 percent chance of not working and tearing into useless, nonmagical tatters.

”What are you writing?”
“Everything you’re saying, I may need to refer to it later.”
“This is preposterous! I am a man of high station. I demand to speak to your—"
"Pre...post...er...."
"Ah, dammit, fine! Have it your way."