In the Serrano creation myth as told by Dorothy Ramon in Always Believe, Coyote is one of three holy beings of the creation: the Lord of the Underworld, the One Above, and Coyote. The Underworld holy one created creatures too big (giants and dinosaurs) who wreaked havok, but Coyote's people were just the right size. The Underworld God departed taking his super-sized creatures below with him, shrinking some like lizards who remained on the surface.

"Coyote was like a man. He behaved like one. He behaved like a joker. That's why they called him Coyote."

Maidu creation myth as retold by Richard Simpson in “Ooti: A Maidu Legacy”
Good and Evil dwell on earth; Good is wisdom of life, or Creation; Evil is ignorance and drowsiness leading to sleep, which is difficult to know or see.  Good must resist the pull of the invisible Evil. Thus there comes a third element, Coyote. Coyote “looks like Evil should, knows what Evil is doing and always does it first; tries to awaken Good to that which Evil is.”  Coyote likes the game he plays, ever loud and full of humor, ever full of tricks and cunning.  Good, seeing evil in Coyote’s antics, must flee in mortal fear.  No matter what Coyote does or says, always do the opposite.

"Coyote has a double personality. he is at once the Creator, and the Fool. this antinomy is very important. Unless you understand it you will miss the Indian psychology completely...The wise man and the buffoon: the two aspects of Coyote, Coyote Old Man." Jaime De Angulo talking about research among the Pit River people of NE California

Gary Snyder, The Maidu Indian Myths and Stories of Hanc'ibyjim, edited by William Shipley (Heyday Books, 1991), pp. viii-ix. 
"Coyote is no stranger, now, to the twentieth century Euroamerican imagination. There are several widely differing interpretations of what he might be. He is seen as a sort of rock musician shaman, or as a culture-hero/trickster who holds contradictory powers and plays a role that is sometimes creative and sometimes destructive, or an archetype of the immature unsocialized ego, or a perennial witty amoral survivor; sometimes he is even the outright principle of evil, the devil.
...."These two characters that are forming (or defining) the world are not, I am sure, representing good and evil principles slugging it out inconclusively.  They step together through a dialectic, a dialog, of ideal and real, with a sinewy final resolution that takes the world as it is.  Even as Earthmaker hopes for a universe without pain and death, Coyote argues for impermanence, for things as they are. As Earthmaker fantasizes a world in which unmarried girls remain virgins and married couples remain celibate, Coyote calls for tickling, lovemaking, and whispering to each other. Earthmaker has a plan for immortality, Coyote insists that there be death. Coyote wins out, ... [and] goes on to finish defining the world which is our present reality.
.... Coyote attends to a world totally phenomenal, but one that is fluid, shape-shifting, role-playing, painful and dirty, but also cheerfully transcended. If Coyote stands up for samsara, the actuality of birth-and-death, it is part of the ultimate paradox that he cannot be killed. He always pulls his scattered conditional self together again, and goes trotting on. In the ongoing tales of Old Man Coyote, we see what could be called "jokes of samsara" played out: outrageous, offensive, and ultimately liberating--into rueful acceptance, courage, and humor." [a poem by Gary Snyder]