What is FX402?

FX402 is a decentralized protocol for defining, pricing, and managing temporary access rights to digital assets.
It extends Coinbase’s x402 — a protocol for HTTP-based payments — with a new profile called R402 (“rent-402”).

🧩 Core Idea

When a user requests a protected resource (e.g., an NFT image or private API endpoint), the server responds with an HTTP 402 Payment Required response containing structured JSON that defines:

Usage tiers — access durations such as 1d, 7d, 30d
Prices — cost per tier, currency, and chain
Rights — what the user is allowed to do (view, remix, commercial-lite)
Payment destination — wallet or facilitator address

Once the payment is made and verified, the user receives a signed receipt granting access for the selected period.

⚙️ What It Enables

Pay-per-duration models for NFTs, media, or ticketed content
Usage-based monetization with transparent terms
Automatic verification via on-chain proofs or facilitator services
Interoperability across web, dApps, and agentic systems — all via HTTP

🔗 Relationship to x402

FX402 is not a replacement for x402 — it’s a profile built on top of it.
x402 defines how payments are handled in HTTP. FX402 (R402) defines what to sell (time-based rights) and how to express it (tiers, receipts).

Every R402 transaction is still a valid x402 transaction — just semantically richer.

🧠 Use Cases

Type	Description
Collectibles	Rent a rare NFT for a week to showcase it in an exhibition.
Tickets	Sell time-limited digital passes that expire automatically.
APIs	Offer data endpoints with per-day or per-month pricing.
Media	Let users pay micro-amounts for temporary viewing or remixing rights.
AI Agents	Agents can rent models, prompts, or datasets on demand.

🧰 Implementation Summary

Server responds with structured R402 requirement JSON
Client or SDK handles payment and retries the request
Server issues a receipt (JWT or JSON) as proof of license
Optional: facilitator service verifies payments and signs receipts

Continue reading How It Works →