AGNTCon + MCPCon Europe 2026

In one year, agents went from unable to pay for anything to spoiled for choice. x402 (Coinbase, now Linux Foundation) for machine-to-machine. AP2 (Google, donated to the FIDO Alliance) for signed payment mandates. ACP (OpenAI and Stripe) for checkout. MPP (Stripe and Tempo, launched March 2026) for streamed micropayments against a pre-authorized session. Four protocols, four layers, real volume.

What none of them owns is the part that decides whether an agent is allowed to spend this, now, on this. MCP returns HTTP 402 inside a tool call, but it has no concept of a budget, an attribution, or an audit trail. The vendor bolt-ons are already multiplying and fragmenting.

And the question stopped being academic. US regulators now treat agent purchases as ordinary card transactions, Europe is moving to put liability on whoever deployed the agent unless they can produce the mandate and audit trail. The receipts are now a legal requirement with no standard home.

This talk maps the four-protocol stack, shows the MCP payment handshake live, and argues for the one layer the agent economy is still missing.