Preheat oven to 375 degrees F (190 degrees C). Grease two cookie sheets.
Mix the flour, baking powder, baking soda, and pumpkin pie spice together in a mixing bowl.
Beat the butter and sugar together in a second mixing bowl until light and fluffy. Beat in the eggs, one at a time, until smooth and well blended. Mix in the pumpkin and vanilla extract until smooth. Gradually add the flour mixture, stirring to make a smooth batter. Stir in the walnuts and chocolate chips. Drop by tablespoon-sized spoonfuls on prepared cookie sheets.
Bake in preheated oven until edges are golden, 18 to 20 minutes. Cool briefly on the cookie sheet before transferring to wire racks to cool completely.