Most companies have spent years building out large API libraries — now the question is how to expose them to autonomous AI agents. Using the Open Bank Project as a real-world test case — a suite of 717+ REST APIs enabling core banking integrations including PSD2 compliance — this session explores practical approaches to bridging existing API infrastructure with agentic AI. Two architectural patterns are examined side by side: the widely known MCP (Model Context Protocol) and a second, lesser-known alternative demonstrated live. Attendees will walk away with concrete strategies for making their existing API investments agent-ready.