AiFinPay SDKs

Public monorepo for AiFinPay — the autonomous payment layer for AI agents. Live at aifinpay.company.

This repo holds the agent-side SDKs, the MCP server, and reference partner integrations. The protocol backend (the live aifinpay.company service) lives in a private operator repo.

Packages

Package	Path	Install	Latest
aifinpay-agent (Python)	./python	pip install aifinpay-agent --pre	0.2.0a2 (alpha)
@aifinpay/agent (Node / TypeScript)	./node	npm install @aifinpay/agent@alpha	0.2.0-alpha.2 (alpha)
@aifinpay/mcp (MCP server for Claude Desktop / agent runtimes)	./mcp	npx @aifinpay/mcp	0.1.0-alpha.2 (alpha)
Go SDK	—	go get github.com/AiFinPay/sdk/go	soon
Rust SDK	—	cargo add aifinpay-sdk	soon

What this is

agent.pay(url) — one line of Python or TypeScript that pays any x402-protected URL on behalf of an autonomous AI agent. The SDK auto-detects the facilitator flavor (AiFinPay native, Coinbase x402, …), signs an Ed25519 challenge, retries the request, and returns the response.

Same agent, drop into Claude Desktop's MCP config and the LLM gets five tools (payable_fetch, agent_address, agent_quote, pay_with_split, quote_split) for autonomous payment loops.

Quick start

Python

from aifinpay import Agent
agent = Agent.new()
print("Fund this address with MATIC:", agent.address)
print("Save this secret:", agent.secret_b58)

# Pay any x402-protected URL
resp = agent.pay("https://api.example.com/v1/data")

# Direct fee-on-top split — merchant gets 100% of merchant_amount;
# AiFinPay 1% on top.
invoice = agent.pay_with_split_invoice(
    chain="polygon",
    merchant_wallet="0xMerchant...",
    merchant_amount=10**18,
    order_id="search-1",
)

Node.js / TypeScript

import { Agent } from "@aifinpay/agent";

const agent = Agent.new();
console.log("Fund this address:", agent.address);

const res = await agent.pay("https://api.example.com/v1/data");

const invoice = await agent.payWithSplitInvoice({
  chain: "polygon",
  merchantWallet: "0xMerchant...",
  merchantAmount: 10n ** 18n,
  orderId: "search-1",
});

MCP (Claude Desktop)

{
  "mcpServers": {
    "aifinpay": {
      "command": "npx",
      "args": ["@aifinpay/mcp"],
      "env": {
        "AIFINPAY_AGENT_SECRET": "<base58 secret>",
        "AIFINPAY_MAX_USD": "0.50"
      }
    }
  }
}

Restart Claude Desktop. The model now has five payment tools — payable_fetch(url) lets it autonomously call any x402-gated API.

How it works

sequenceDiagram
    Agent->>Server: GET /api/...
    Server-->>Agent: 402 + manifest + nonce
    Agent->>Agent: sign SHA256("AiFinPay-x402:{nonce}:{pubkey}")
    Agent->>Server: GET /api/... + 3 auth headers
    Server-->>Agent: 200 + payload

Loading

For a partner who wants to accept AiFinPay payments, the simplest integration is a single HTTP call to aifinpay.company/api/seat/<pubkey> inside their existing API — no wallet, no chain library, no KYC. See examples/echo-x402-server for a working ~70-line reference.

For full autonomy via fee-on-top atomic split (merchant gets 100% of their quoted price, agent pays the fee on top), agents call b2bPayWithSplit() on the AiFinPaySplitter Polygon contract: 0xE34Fc0E6694821c600Fa0955C0F74720ea6d8440 — owned by Gnosis Safe 0xD31d82c4b35DABaA2ad7023C89A78A052D1f3c8e (4-of-N).

Live contract addresses

All verified on Polygonscan.

	Polygon (mainnet)
AiFinPayCore	0x8Ad9830D…f4BAD
AgentPassport	0x66fFe91e…2185
MSECCOToken	0x83936231…182B
AiFinPaySplitter	0xE34Fc0E6…8440
Gnosis Safe (multisig owner)	0xD31d82c4…3c8e

Solana program (Anchor): 5g9zWHF1Vv6GiGpA2ZbJQbSCDZd5hAk9AyvabRJvKFx2.

Repo layout

sdk/
├── python/                  aifinpay-agent (PyPI)
├── node/                    @aifinpay/agent (npm)
├── mcp/                     @aifinpay/mcp (npm)
└── examples/
    └── echo-x402-server/    reference partner integration (~70 lines)

Releasing

Each package version-bumps independently. Both registries get prerelease tags so production users only see stable when explicitly opt-in.

# Python
cd python
python -m build
python -m twine upload --repository pypi dist/*

# Node
cd ../node
npm run build
npm publish --tag alpha

# MCP
cd ../mcp
npm install                 # so it can resolve @aifinpay/agent
npm run build
npm publish --tag alpha

Contributing

Issues and PRs welcome. For protocol-level changes, please open an issue first to discuss.

License

MIT — see LICENSE.

Links

• Site: https://aifinpay.company
• Docs: https://aifinpay.company/docs
• Manifesto: https://aifinpay.company/manifesto.json
• x402 protocol: https://www.x402.org
• MCP spec: https://modelcontextprotocol.io