primer-x402 1.1.0

Primer ecosystem toolkit for x402

primer-x402

Primer ecosystem toolkit for x402. Built on the official x402 SDK.

This package extends the official x402 SDK with Primer-specific infrastructure: our facilitator, SKALE network support, Robinhood Chain support, and Prism ERC-20 settlement.

Installation

pip install primer-x402

This automatically installs x402 as a dependency.

Quick Start

Using Primer's Facilitator

from primer_x402 import primer_facilitator, primer_facilitator_sync

# Async client
facilitator = primer_facilitator()
result = await facilitator.verify(payload, requirements)

# Sync client
facilitator_sync = primer_facilitator_sync()
result = facilitator_sync.verify(payload, requirements)

SKALE Networks (Gas-Free)

from primer_x402 import skale_networks

# Use SKALE for gas-free transactions
network = skale_networks.base           # "eip155:1187947933"
network = skale_networks.base_sepolia   # "eip155:324705682"

Robinhood Chain

from primer_x402 import robinhood_networks

# Use Robinhood Chain
network = robinhood_networks.mainnet    # "eip155:4663"
network = robinhood_networks.testnet    # "eip155:46630"

Prism ERC-20 Settlement

For standard ERC-20 tokens (not USDC/EURC), use Prism:

from eth_account import Account
from web3 import Web3
from primer_x402 import create_prism_payload, PrismPaymentParams

web3 = Web3(Web3.HTTPProvider("https://mainnet.base.org"))
account = Account.from_key("0x...")

payload = create_prism_payload(
    account,
    web3,
    PrismPaymentParams(
        token="0x...",  # ERC-20 token address
        to="0x...",     # Recipient
        value=1000000,  # Amount in smallest unit
    ),
    "eip155:8453",
)

Note: Payers must first approve the Prism contract (0x402357ff1e18d42d0f14a5d56d6e1ebd741b3a86) to spend their tokens.

CLI

The package includes a CLI for scaffolding new x402 projects.

Create a Paid AI Proxy (Chutes)

Scaffold a FastAPI server that proxies Chutes (Bittensor Subnet 64) AI endpoints with x402 micropayments:

primer-x402 create chutes-proxy my-ai-api
cd my-ai-api
python -m venv venv
source venv/bin/activate  # or venv\Scripts\activate on Windows
pip install -r requirements.txt

Edit main.py to set your wallet address:

RECIPIENT = "0xYourWalletAddress"

Set your Chutes API key and run:

cp .env.example .env
# Edit .env with your CHUTES_API_KEY
export $(cat .env | xargs)
uvicorn main:app --reload

The generated proxy exposes these paid endpoints:

Endpoint	Default Price
/v1/chat/completions	$0.001
/v1/completions	$0.001
/v1/embeddings	$0.0001
/v1/images/generations	$0.01

Payments are verified via Primer's facilitator and accepted on Base mainnet. Edit the generated code to customize pricing, networks, or add additional endpoints.

API Reference

Facilitator

Export	Description
primer_facilitator()	Async client for x402.primer.systems
primer_facilitator_sync()	Sync client for x402.primer.systems
PRIMER_FACILITATOR_URL	"https://x402.primer.systems"

Networks

Export	Value
skale_networks.base	"eip155:1187947933"
skale_networks.base_sepolia	"eip155:324705682"
skale_rpc_urls.base	"https://skale-base.skalenodes.com/v1/base"
skale_rpc_urls.base_sepolia	"https://base-sepolia-testnet.skalenodes.com/v1/..."
robinhood_networks.mainnet	"eip155:4663"
robinhood_networks.testnet	"eip155:46630"
robinhood_rpc_urls.mainnet	"https://rpc.mainnet.chain.robinhood.com"
robinhood_rpc_urls.testnet	"https://rpc.testnet.chain.robinhood.com"

Prism Settlement

Export	Description
create_prism_payload(account, web3, params, network)	Create signed ERC-20 payment
get_prism_nonce(web3, user, token)	Get current nonce for user/token
PrismPaymentParams	Dataclass for payment parameters
PrismPayload	TypedDict for the resulting payload
PRISM_CONTRACT_ADDRESS	"0x402357ff1e18d42d0f14a5d56d6e1ebd741b3a86"
PRISM_ABI	Contract ABI (minimal)
ERC20_PAYMENT_TYPES	EIP-712 type definitions

Supported Networks

Network	Chain ID	Facilitator
Base	eip155:8453	✓ Primer
Base Sepolia	eip155:84532	✓ Primer
SKALE Base	eip155:1187947933	✓ Primer
SKALE Base Sepolia	eip155:324705682	✓ Primer
Robinhood Chain	eip155:4663	✓ Primer
Robinhood Chain Testnet	eip155:46630	✓ Primer

Links

• x402 Protocol
• Official x402 SDK
• Primer Systems
• TypeScript SDK

License

Apache-2.0 — Primer Systems