A DSP acting as a sending service provider gives the ATO the details of its model and value chain: its intended business model (offered to market or used for its own products), the functional roles it performs in the supply chain, the services offered (file upload, portal, REST API), whether it uses the same infrastructure as existing products, and the service architecture including shared infrastructure, and may be asked for published product descriptions and screenshots of the connection method. Sending service providers fall in category A.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.