what is this tiny bug.
The insect in your digital image is an elm seed bug, Arocatus melanocephalus. This is a relatively new invasive insect pest found in a number of states in the Pacific Northwest. This is not a crop pest, but considered to be a nuisance pest that invades households, particularly in late summer, early autumn to seek shelter from winter weather.
The plant host is primarily elm trees- Chinese or Siberian elms that grow like weeds in the Central WA state. The best management strategy would be to remove the host plant. The next strategy would be to find out how the bugs get into the home and seal, screen or otherwise keep them out of the house.
For more info on elm seed bug:
https://pnwhandbooks.org/insect/emerging-pacific-northwest-ornamentals (scroll down on this website)
Hope this helps!