Explainer · TIER_B

What is MCP?

A standard way for models to list and call tools. It is not itself a payment protocol.

zFinia published 7 September 2026

The Model Context Protocol, open-sourced by Anthropic on 25 November 2024, defines how a host (the model runtime) talks to servers that expose tools, resources and prompts.

MCP solved a proliferation of one-off integrations. It did not solve billing. tools/list and tools/call tell an agent what it can do, not what it owes.

Paid MCP is an overlay

Cloudflare’s gateway, x402 challenge-handoff and MPP all propose to hang payment on the same tool call. Until the MCP spec itself names a payment profile, “paid MCP” remains a market category, not a single standard.

zFinia covers that category because developers keep asking how to monetize MCP. Questions are buyer-hand-raises. Proven demand still requires payments, not comments.

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