1. A method for rule execution in decision services, comprising: providing, by one or more processors, one or more specialized rulesets classified by decision partitions based on defined clustering predicates of decision service signatures for business rules, wherein a clustering predicate is a function that determines a decision category based on parameters that are input into the function, wherein the clustering predicate is based on the decision service signature, wherein the decision service signatures define input parameters and output parameters for a decision service, wherein the decision service is an autonomous component that receives decision requests and return decision outputs; receiving, by one or more processors, a decision request from a client, wherein the decision service redirects the decision request to a particular set of business rules; inputting, by one or more processors, one or more parameters of the decision request to a clustering predicate based on the decision service signatures to produce the decision category; determining, by one or more processors, a specialized ruleset for the decision request based on the decision category; forwarding, by one or more processors, the decision request for processing by the specialized ruleset; returning, by one or more processors, a decision output from the specialized ruleset; defining, by one or more processors, the clustering predicate at business rules authoring time; analyzing, by one or more processors, business rules to identify decision partitions based on the clustering predicate and to classify the business rules per decision partition to form specialized rulesets, wherein said analyzing the business rules includes: scanning, by one or more processors, all business rules for all conditions in the business rules; scanning, by one or more processors, all conditions for all tests performed on the decision partitions; adding, by one or more processors, a new decision partition; adding a test to the new decision partition; and adding the test to a default decision partition.