The supplier's engineering team makes sure every requirement can be traced both upwards to its source and downwards to what implements and verifies it, maintains a requirements traceability matrix to the RTM document requirements definition, and records the close-out of each requirement in the verification control document as ECSS-E-ST-10-02 prescribes.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.