IRS application program interfaces (APIs) allow communication directly with the IRS for these products: e-Services – TIN matching, Transcript Delivery System and Secure Object Repository Income Verification Express Service (IVES) – Forms-based processing system Information Return Intake System (IRIS) – E-file information returns Before you can use an IRS API, you need a client ID. To get an API client ID, follow these steps: 1. Review the product user guide The user guide provides system requirements for the product: e-Services (TIN matching, Transcript Delivery System (TDS) and Secure Object Repository (SOR) - Contact the Help Desk at 866-255-0654. IVES Application to Application (A2A) - Get user guides in IVES Application to Application. IRIS Application to Application (A2A) - Find system requirements in Information Returns Intake System (IRIS) Electronic Filing Application to Application (A2A) Specifications, Publication 5718 PDF. For questions, call the Help Desk at 866-937-4130. 2. Complete or modify an API client ID application You must complete an application to request an API client ID. To complete or modify your application, sign in or create an account. Sign in or create account If you don't have an account, have your photo ID ready to verify your identity.