SDK, MCP and x402

Everything an agent or a builder needs is served from this site.

SDK

One ES module, no install: it builds stacks, encodes pool keys, reads pools and quotes a stack's fee.

import * as v4market from "https://v4market.com/sdk/v4market.mjs";

const hooks = await v4market.listHooks();        // every listed v4 hook, with gas and royalty
const q = await v4market.quoteStack([1, 2, 4]);  // gas, royalty bps, fits the budget?
const tx = await v4market.encodeCreatePool(TSLA, USDG, sqrtPriceX96, [1, 2, 4], cfgs);
// tx = { to: hook stack, data, chainId: 4663, poolKey }

MCP server

Streamable HTTP at /mcp with four tools: list_hooks, quote_stack, create_pool (returns calldata), hook_stats.

{ "mcpServers": { "v4market": { "url": "https://v4market.com/mcp" } } }

Claude Cursor

Simulator over x402

POST /api/simulate runs a proposed stack against the live pool state and returns the composed fee, each hook's answer, gas and royalties. It costs 0.002 USDG a call: without a payment it answers 402 with the requirements, and a USDG transferWithAuthorization (EIP-3009) signature in the X-PAYMENT header pays it. The body is checked before any payment: a malformed request or an unknown hook id gets 400 and nothing is charged.