Fluid Agentic DeFi Protocol (FADP/1.0): HTTP-Native Micropayment Authentication for Autonomous AI Agents
draft-fluid-fadp-01
| Document | Type |
Expired Internet-Draft
(individual)
Expired & archived
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|---|---|---|---|
| Author | Abhijeeth Ganji | ||
| Last updated | 2026-10-25 (Latest revision 2026-04-23) | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | Expired | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:
Abstract
This document defines the Fluid Agentic DeFi Protocol (FADP), version 1.0. FADP is an application-layer protocol layered atop HTTP that enables autonomous AI agents to pay for access to web resources using on-chain cryptocurrency transfers, with cryptographic proof of payment embedded directly in HTTP headers. FADP extends HTTP 402 (Payment Required) with two new header fields: X-FADP-Required, which a server uses to communicate payment terms to an agent, and X-FADP-Proof, which an agent uses to supply a verifiable on-chain payment receipt. A nonce-challenge mechanism prevents proof replay. An optional verification endpoint allows third-party on-chain confirmation without requiring the verifying party to run blockchain infrastructure. FADP is designed for agent-to-server and agent-to-agent payment flows operating at sub-dollar granularity (micropayments), where credit- card or OAuth-based billing is impractical. The reference implementation targets USDC on Base (an Ethereum Layer 2), though the protocol is token- and chain-agnostic.
Authors
(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)