finicky

/ˈfɪnɪki/
adjective
  1. Very particular or hard to please, especially about small or unimportant details.
    • He's finicky about his tools and cleans them after every single use.
    • My grandmother is finicky about the way her tea is brewed and will send it back if it's not perfect.
    • The toddler was finicky at dinner, pushing away anything that wasn't macaroni and cheese.
  2. Requiring careful attention to detail; delicate or tricky to handle or operate.
    • The old printer is finicky and often jams if you don't load the paper exactly straight.
    • This recipe is finicky; even a small change in temperature can ruin the sauce.
    • The lock on the back door is finicky and you have to jiggle the key just right to open it.