Glossary

Protocol

Commerce protocol stack

The emerging set of agent-readable commerce standards: MCP, WebMCP, A2A, UCP, ACP, AP2, and payment rails.

Definition

The commerce protocol stack is the set of standards and interface patterns that let agents discover tools, coordinate with other agents, read product evidence, propose orders, and eventually transact through governed rails.

Why it matters

Protocol readiness determines whether a merchant is legible to agents and whether agentic commerce can be controlled rather than improvised.

How HARNEXA uses it

HARNEXA maps the stack in the agentic commerce readiness hub and keeps public execution disabled until identity, permission, approval, evidence, and support gates hold.

FAQ

Questions this definition answers.

Is protocol readiness the same as public execution?

No. HARNEXA separates readiness and evidence from public tool execution.

Which protocols are most relevant now?

MCP, WebMCP, A2A, UCP, ACP, AP2, and payment-specific rails such as x402 each cover a different part of the stack.

Related terms

ProtocolMCP (Model Context Protocol)An open standard for connecting AI systems to tools and data sources.ProtocolWebMCPA browser-context approach for exposing website actions as structured tools for AI agents.ProtocolUCP (Universal Commerce Protocol)A commerce protocol direction for turning AI interactions into direct buying while merchants retain control.

Need these definitions mapped to a live commerce workflow, agent estate, or protocol-readiness path?

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