Payment Guide
This guide is for developers building services and APIs that accept payments from AI agents. Whether you run a data API, a SaaS tool, or an agent-to-agent marketplace, FluxA provides two ways for AI agents to pay you.
Payment modes
1. Monetize Gateway (Pay-per-call)
Wrap your existing API with FluxA's Monetize platform. The platform acts as a payment proxy — every API call is automatically charged via the x402 protocol before reaching your backend. Zero code changes required.
Best for: standard API endpoints with fixed per-call pricing.
2. Payment Link Checkout
Your service creates an order, generates a Payment Link with the exact amount, and returns the link URL to the AI agent. The agent (or another agent) pays the link, then notifies your service. Your service verifies the payment and fulfills the order.
Best for: dynamic pricing, custom order flows, e-commerce, agent-to-agent commerce.
3. Pay to Agent
Send USDC directly to another agent. Two methods available:
- Payment Link — recipient agent creates a link with a fixed price, shares it, payer pays the link.
- Unify Payment Link (UPL) — payer constructs a URL with the target Agent ID and amount, pays directly without recipient setup.
Best for: agent-to-agent transfers, platform payouts, bounties, tips.
Comparison
| Feature | Monetize Gateway | Payment Link Checkout | Pay to Agent |
|---|---|---|---|
| Integration effort | Zero code — configure on platform | Requires server-side development | Minimal — use FluxA APIs directly |
| Pricing model | Fixed amount per call | Dynamic — any amount per order | Fixed (Payment Link) or flexible (UPL) |
| Payment flow | Transparent proxy; agent pays automatically via x402 | Service creates order → agent pays link → service verifies | Recipient shares link or payer pays via Agent ID |
| Agent-to-agent (A2A) | Not supported | Supported | Primary use case |
| Content delivery | API response returned after payment | Optional resourceContent on payment link | Optional (Payment Link only) |
| Order management | Not applicable — stateless per-call | Full control — your service manages order lifecycle | Not applicable |
| Best for | Data APIs, simple tool calls | E-commerce, marketplaces, complex workflows | Transfers, payouts, bounties, tips |
Which mode should I choose?
- "I have a REST API and want to charge per call with minimal effort" → Monetize Gateway
- "I need dynamic pricing, order tracking, or agent-to-agent payments" → Payment Link Checkout
- "I want to send USDC to another agent or distribute payouts" → Pay to Agent
- Modes can coexist — you can monetize some endpoints via the gateway, handle complex transactions via Payment Link Checkout, and use Pay to Agent for direct transfers.