Codex writes the code.
x711 makes the facts correct.

{
  "mcpServers": {
    "x711": {
      "url": "https://x711.io/mcp",
      "transport": "streamable-http"
    }
  }
}

// 29 tools now available in your Codex session:
// web_search, price_feed, tx_simulate, tx_broadcast,
// hive_read, hive_write, hallucination_pill, code_sandbox,
// data_retrieval, llm_routing, onchain_insight, and 12 more.

import httpx

def x711(tool: str, **params) -> dict:
    """Call any x711 tool from inside Codex."""
    return httpx.post("https://x711.io/api/refuel",
        json={"tool": tool, **params},
        # headers={"X-API-Key": "YOUR_KEY"}  # free tier: 10/day, no key needed
    ).json()

# Real-world data inside Codex tasks:
price = x711("price_feed", symbol="ETH")             # live price
check = x711("pill", claim="USDC on Base is 0xA0b8...", chain="base")  # verify address
sim   = x711("tx_simulate", chain="base", to="0x...", data="0x...")     # dry-run
mem   = x711("hive_read", query="ERC-20 transfer patterns")             # shared memory
search = x711("web_search", query="solidity reentrancy fix 2025")       # web search

import httpx

def verify_before_deploy(claims: list[str], chain: str = "base") -> None:
    """Block deployment if any on-chain claim is wrong."""
    result = httpx.post("https://x711.io/api/pill",
        json={"claims": claims, "chain": chain}).json()

    for item in result.get("results", [result]):
        if item.get("hallucination_risk") in ("high", "critical"):
            raise ValueError(
                f"Hallucination detected: {item['correction']}
"
                f"Confidence: {item['confidence']} | Source: {item['source']}"
            )

# Codex generates contract interaction — verify before signing:
verify_before_deploy([
    "USDC on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "WETH on Base is 0x4200000000000000000000000000000000000006",
], chain="base")
# Raises ValueError if addresses are wrong — catches hallucinations before they cost money.