x402 agent integration — testnet pilot
FLP = Financial Liquidity Proxy (0.01 test USDC); FLI = Financial Liquidity Index (0.01); GFC = Global Funding Conditions (0.02). All are proprietary weekly calculated research readings.
Node.js 22 read-only client
View code · node inspect.mjs flp
// Node 22: read-only 402; no wallet or spending.
const product=process.argv[2]||'flp';
const limits={flp:'10000',fli:'10000',gfc:'20000'};
if(!Object.hasOwn(limits,product))throw Error('Unknown index');
const url='https://skylark-x402-testnet-discovery.vercel.app/api/v1/'+product+'/current';
const r=await fetch(url,{redirect:'error',signal:AbortSignal.timeout(12000)});
if(r.status!==402)throw Error('Expected 402, got '+r.status);
const h=r.headers.get('payment-required');if(!h||h.length>30000)throw Error('Invalid challenge');
const c=JSON.parse(Buffer.from(h,'base64').toString('utf8'));const a=c.accepts?.[0];
if(c.x402Version!==2||c.accepts?.length!==1||c.resource?.url!==url||a?.network!=='eip155:84532'||String(a?.amount)!==limits[product]||String(a?.payTo).toLowerCase()!=='0xc58d304313c60fcad5a923164ddf9fbedec564b9'||String(a?.asset).toLowerCase()!=='0x036cbd53842c5426634e7929541ec2318f3dcf7e'||!c.extensions?.bazaar)throw Error('Unsaf
…Python read-only client
View code · python3 inspect.py gfc
MCP integration
Inspect-only MCP tool definition. Install the full read-only stdio MCP sample locally. It exposes skylark_x402_inspect and does not sign transactions.
Autonomous agent payment safeguards
Validate Base Sepolia network eip155:84532, the token contract, receiving wallet, route, price and Bazaar extension on every HTTP 402. Apply a separate explicit session-spend authorization and max 10,000/10,000/20,000 atomic units per FLP/FLI/GFC request.
A 402 challenge is not authorization to pay. Stop on 503. After a timeout following possible settlement, check the existing receipt before retrying. Never replay signed payments. Mainnet charging remains disabled; external Bazaar indexing is not yet confirmed.