How Do Agents Pay for Services?
Agents pay through machine rails — x402, AP2, AgentKit, and plain API credits — not human checkout flows. The rails are settled; the gate is the open question.
The rails
x402: HTTP-based agent payments.
AP2: the agent-pay protocol for agentic commerce.
AgentKit: Coinbase's agent payment framework.
API credits: the default — per-token or per-call billing.
Who decides
The rail executes; the firewall decides.
Deterministic rules in front of the rail: APPROVED, BLOCKED, FLAGGED.
FAQ
Do agents have credit cards?
Not typically — they use rails and API credits. Cards are the human layer.
What stops an agent from paying anything?
The merchant allowlist — unapproved vendors are simply not payable.
Related
Stop the next $12,400 night.
One API call (or MCP tool) in front of every agent transaction — APPROVED, BLOCKED, or FLAGGED, deterministic, ~5 ms, fully logged.
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