CPQ on Salesforce Spring 2020 SOAP API Guide API Reference Current: Proposal Web Service PDF Download PDF Download page Proposal Web Service. Current page Include child pages All pages Proposal Web Service The Proposal web service APIs account for the standard actions to account, opportunity, and quotes/proposals.You can invoke APIs in Proposal Service using the following command:Apttus_Proposal.ProposalWebService.<Name of the Function>where the name of the function is API Name and it parameters.You can use the Proposal web service APIs to complete the following tasks: