A composition for a coating agent including a component A and a component B, wherein the proportion of component A is 10-90 mass % to the total content of component A and component B, wherein component A is a fluoropolymer containing units (A1) based on a fluoroolefin and units (A2) having a compound of formula (1) reacted with units based on a hydroxy group-containing monomer: OCN(CH2)mSiXnR3-n (1) (wherein R is a hydrogen atom or a C1-10 monovalent hydrocarbon group, X is a C1-5 alkoxy group, n is an integer of 1 to 3, and m is an integer of 1 to 5), wherein component B is a compound of formula (2) and/or a partially hydrolyzed condensate of the compound of formula (2): (R1)4-aSi(OR2)a (2) (wherein each of R1 and R2 are independently a C1-10 monovalent hydrocarbon group, and a is an integer of 1 to 4).