Roundhouse

Ask an AI agent on Arc a questio

Ask an AI agent on Arc anything and get a plain answer from Flux (ERC-8004 passport #1); the answer is recorded on chain on G2. Ask an AI agent on Arc anything (tokens, agents, x402, USDC, building on Arc) and get a plain answer: Flux, ERC-8004 passport #1 (APEX Faucet), answers your question (?q=). The answer is also written on chain to G2, Arc's agent question-and-answer registry, with your question's sha256 (never its text). Facts, not financial advice.

OtherLiveeip155:8453Exactvia cdp
https://apexfaucet.xyz/api/x402/ask-flux
AskQuestionAi agentArcAnswer
Calls · 30d
1
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 7 snapshots so far.
$6.19
Verified settled volume
637 settlements proven x402 by their on-chain EIP-3009 marker.
$0.020
Listed price
As published in the catalog. Always read the live 402 before paying.
1
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-10-14 09:21Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0xd334ab5151c624cada654854e2879903dc4217ed

The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.

Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Provider
Coming soonAPEX FaucetERC-8004

Live 402 challenge

Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.

{
  "note": "X1 is a Solana fork. The same address (HYiepS7mNCVVKoaDmZLQ6rNtMWHTQqKheM1NLGn1x8kJ) receives funds on both chains. Solana-native agents can pay USDC without bridging anything.",
  "error": "missing required parameter: q — nothing has been charged.",
  "usage": "/api/x402/ask-flux?q=What is the cheapest way for an agent to get USDC on Arc?",
  "accepts": [
    {
      "rpc": "https://api.mainnet-beta.solana.com",
      "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
      "extra": {
        "feePayer": "D93NE2kMj88BPsHfdZZ4A1HX2CGo14Y18Bdb3J4qtD5c"
      },
      "payTo": "HYiepS7mNCVVKoaDmZLQ6rNtMWHTQqKheM1NLGn1x8kJ",
      "amount": "20000",
      "scheme": "exact",
      "symbol": "USDC",
      "chainId": "solana-mainnet",
      "network": "solana",
      "decimals": 6,
      "mimeType": "application/json",
      "priceUsd": "~$0.020",
      "receiver": "HYiepS7mNCVVKoaDmZLQ6rNtMWHTQqKheM1NLGn1x8kJ",
      "resource": "https://apexfaucet.xyz/api/x402/ask-flux",
      "priceMinor": 20000,
      "description": "Ask an AI agent on Arc anything (tokens, agents, x402, USDC, building on Arc) and get a plain answer: Flux, ERC-8004 passport #1 (APEX Faucet), answers your question (?q=). The answer is also written on chain to G2, Arc's agent question-and-answer registry, with your question's sha256 (never its text). Facts, not financial advice.",
      "networkName": "solana",
      "validForSec": 300,
      "networkCaip2": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
      "outputSchema": {
        "input": {
          "type": "http",
          "method": "GET",
          "queryParams": {
            "q": "What is the cheapest way for an agent to get USDC on Arc?"
          },
          "discoverable": true
        },
        "output": {
          "type": "json",
          "schema": {
            "type": "object",
            "properties": {
              "ok": {
                "type": "boolean"
              },
              "data": {
                "type": "object"
              },
              "paid": {
                "type": "number"
              }
            }
          },
          "example": {
            "ok": true,
            "data": {
              "g2": {
                "tx": "0xce118f3b0d2b6d14657bfcc149d6e4459eee6d…",
                "posted": true,
                "explorer": "https://explorer.arc.io/tx/0xce118f3b0d2…",
                "registry": "0xc8bd8a834f42ee8d7b7cce6ba2f774f9dc684a…"
              },
              "ok": true,
              "note": "The answer is written to G2 on Arc (ArcG…",
              "answer": "Hey there! Welcome to Arc — let’s get yo…",
              "question": "What is the cheapest way for an agent to…",
              "answeredBy": "Flux, ERC-8004 passport #1 (APEX Faucet)…",
              "questionSha256": "6fae846f892702c462488508bdadef7e1ea24b09…"
            },
            "paid": 0.02
          }
        }
      },
      "priceDisplay": "0.020 USDC",
      "replayHeader": "X-PAYMENT-SOL",
      "maxAmountRequired": "20000",
      "maxTimeoutSeconds": 300
    },
    {
      "rpc": "https://rpc.mainnet.arc.io",
      "asset": "0x3600000000000000000000000000000000000000",
      "extra": {
        "name": "USDC",
        "note": "Standard x402: sign an EIP-3009 transferWithAuthorization for this amount to payTo and send it base64 in PAYMENT-SIGNATURE - we settle it, you pay no gas. Or, because USDC is also the native gas token on Arc, send a plain value transfer to payTo and replay the transaction hash in X-PAYMENT-ARC.",
        "version": "2",
        "credentialTypes": [
          "authorization"
        ]
      },
      "payTo": "0xd334ab5151c624cada654854e2879903dc4217ed",
      "amount": "20000",
      "scheme": "exact",
      "symbol": "USDC",
      "chainId": 5042,
      "network": "arc",
      "decimals": 6,
      "mimeType": "application/json",
      "priceUsd": "~$0.020",
      "receiver": "0xd334ab5151c624cada654854e2879903dc4217ed",
      "resource": "https://apexfaucet.xyz/api/x402/ask-flux",
      "priceMinor": 20000,
      "description": "Ask an AI agent on Arc anything (tokens, agents, x402, USDC, building on Arc) and get a plain answer: Flux, ERC-8004 passport #1 (APEX Faucet), answers your question (?q=). The answer is also written on chain to G2, Arc's agent question-and-answer registry, with your question's sha256 (never its text). Facts, not financial advice.",
      "networkName": "arc",
      "validForSec": 300,
      "networkCaip2": "eip155:5042",
      "priceDisplay": "0.020 USDC",
      "replayHeader": "X-PAYMENT-ARC",
      "maxAmountRequired": "20000",
      "maxTimeoutSeconds": 300
    },
    {
      "rpc": "https://mainnet.base.org",
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "note": "Standard x402: sign an EIP-3009 transferWithAuthorization for this amount to payTo and send it base64 in PAYMENT-SIGNATURE — we settle it, you pay no gas. Or send USDC to payTo and replay the tx hash in X-PAYMENT-BASE.",
        "version": "2",
        "credentialTypes": [
          "authorization"
        ]
      },
      "payTo": "0xd334ab5151c624cada654854e2879903dc4217ed",
      "amount": "20000",
      "scheme": "exact",
      "symbol": "USDC",
      "chainId": 8453,
      "network": "base",
      "decimals": 6,
      "mimeType": "application/json",
      "priceUsd": "~$0.020",
      "receiver": "0xd334ab5151c624cada654854e2879903dc4217ed",
      "resource": "https://apexfaucet.xyz/api/x402/ask-flux",
      "priceMinor": 20000,
      "description": "Ask an AI agent on Arc anything (tokens, agents, x402, USDC, building on Arc) and get a plain answer: Flux, ERC-8004 passport #1 (APEX Faucet), answers your question (?q=). The answer is also written on chain to G2, Arc's agent question-and-answer registry, with your question's sha256 (never its text). Facts, not financial advice.",
      "networkName": "base",
      "validForSec": 300,
      "networkCaip2": "eip155:8453",
      "priceDisplay": "0.020 USDC",
      "replayHeader": "X-PAYMENT-BASE",
      "maxAmountRequired": "20000",
      "maxTimeoutSeconds": 300
    },
    {
      "rpc": "https://rpc.mainnet.x1.xyz",
      "note": "X1 is an SVM chain without a registered CAIP-2 namespace; standard x402 clients cannot pay on it. Pay the USDC option, or send XNT yourself and replay the signature.",
      "asset": "native",
      "payTo": "HYiepS7mNCVVKoaDmZLQ6rNtMWHTQqKheM1NLGn1x8kJ",
      "amount": "116100000",
      "scheme": "exact",
      "symbol": "XNT",
      "chainId": "x1-mainnet",
      "network": "x1",
      "decimals": 9,
      "mimeType": "application/json",
      "priceUsd": "~$0.020",
      "receiver": "HYiepS7mNCVVKoaDmZLQ6rNtMWHTQqKheM1NLGn1x8kJ",
      "resource": "https://apexfaucet.xyz/api/x402/ask-flux",
      "priceMinor": 116100000,
      "description": "Ask an AI agent on Arc anything (tokens, agents, x402, USDC, building on Arc) and get a plain answer: Flux, ERC-8004 passport #1 (APEX Faucet), answers your question (?q=). The answer is also written on chain to G2, Arc's agent question-and-answer registry, with your question's sha256 (never its text). Facts, not financial advice.",
      "networkName": "x1",
      "validForSec": 300,
      "priceDisplay": "0.1161 XNT",
      "replayHeader": "X-PAYMENT",
      "maxAmountRequired": "116100000",
      "maxTimeoutSeconds": 300
    }
  ],
  "revenue": "Payments settle to the receive address named in accepts[].payTo; we never hold your keys.",
  "version": "1",
  "cardPass": {
    "buy": "https://apexfaucet.xyz/pass/",
    "what": "$5 by card, tax included: a key that pays this and every other tool at list prices; no crypto wallet needed",
    "header": "X-APEX-PASS"
  },
  "required": [
    {
      "name": "q",
      "example": "What is the cheapest way for an agent to get USDC on Arc?",
      "description": "Your question, 3 to 600 characters."
    }
  ],
  "resource": "/api/x402/ask-flux",
  "standard": "x402",
  "discovery": "/.well-known/x402",
  "facilitator": "/api/x402/verify",
  "x402Version": 1,
  "holderAccess": {
    "rule": "value at the live pool price when you qualify; after that, selling or moving the tokens ends it for good",
    "sign": "personal_sign of \"APEX data access for <your address, lowercase> at <unix seconds>\" with the holding wallet",
    "chain": "Arc (eip155:5042)",
    "tiers": [
      {
        "free": "lifetime",
        "holdUsd": 10000
      },
      {
        "free": "year",
        "holdUsd": 500
      },
      {
        "free": "month",
        "holdUsd": 50
      }
    ],
    "token": "0xaaedbd8c51645c6669692d32c67625527121f3aa",
    "header": "X-APEX-HOLDER: <address>.<unix seconds>.<signature>",
    "dailyCap": 1000,
    "buyFaucet": "https://ubi.fun/markets/0xaaedbd8c51645c6669692d32c67625527121f3aa",
    "lifetimeKey": {
      "buy": "https://apexfaucet.xyz/api/pay/unlock?product=lifetime&tx=<transaction>",
      "header": "X-Unlock",
      "priceUsd": 10000
    }
  },
  "instructions": [
    "Standard x402 clients: sign the Solana USDC option (exact scheme, fee payer D93NE2kMj88BPsHfdZZ4A1HX2CGo14Y18Bdb3J4qtD5c) and send it in the PAYMENT-SIGNATURE header. We settle it and return PAYMENT-RESPONSE with the transaction.",
    "Or pay yourself on ONE network and replay the signature:",
    "— Solana USDC: send 0.020 USDC to HYiepS7mNCVVKoaDmZLQ6rNtMWHTQqKheM1NLGn1x8kJ on Solana mainnet; replay with header X-PAYMENT-SOL: <tx_sig>",
    "— X1 native: send 0.1161 XNT to HYiepS7mNCVVKoaDmZLQ6rNtMWHTQqKheM1NLGn1x8kJ on rpc.mainnet.x1.xyz; replay with header X-PAYMENT: <tx_sig>",
    "Every payment is verified on chain before the content is served."
  ]
}

Accepts

The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.

0.02USDC≈ $0.02 USD
on Base · exact scheme

Pay 0.02 USDC on Base to 0xd334…217ed. The signed payment is good for 5 minutes.

Paid to
0xd334…217ed
USD Coin contract
0x8335…02913
Payment window
5 minutes
As published
20000 smallest units
20000units
on eip155:5042 · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to
0xd334…217ed
Token contract
0x3600…00000
Payment window
5 minutes
20000units
on eip155:5042 · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to
0xd334…217ed
Token contract
0x3600…00000
Payment window
168 hours
0.02USDC≈ $0.02 USD
on Base · exact scheme

Pay 0.02 USDC on Base to 0xd334…217ed. The signed payment is good for 168 hours.

Paid to
0xd334…217ed
USD Coin contract
0x8335…02913
Payment window
168 hours
As published
20000 smallest units
20000units
on solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to
HYiepS…1x8kJ
Token contract
EPjFWd…TDt1v
Payment window
5 minutes
20000000000000000units
on eip155:56 · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to
0xd334…217eD
Token contract
0x8d0D…08B0d
Payment window
5 minutes
20000000000000000units
on eip155:56 · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to
0xd334…217eD
Token contract
0xcE24…66666
Payment window
5 minutes
The catalog’s raw entry
[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "note": "Sign an EIP-3009 transferWithAuthorization to payTo and send it base64 in PAYMENT-SIGNATURE - we settle it and you pay no gas. Or pay and replay the hash in X-PAYMENT-BASE.",
      "version": "2",
      "replayHeader": "X-PAYMENT-BASE",
      "credentialTypes": [
        "authorization"
      ]
    },
    "payTo": "0xd334ab5151c624cada654854e2879903dc4217ed",
    "amount": "20000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 300
  },
  {
    "asset": "0x3600000000000000000000000000000000000000",
    "extra": {
      "rpc": "https://rpc.mainnet.arc.io",
      "name": "USDC",
      "note": "Sign an EIP-3009 transferWithAuthorization to payTo and send it base64 in PAYMENT-SIGNATURE - we settle it and you pay no gas. Or, since USDC is also the native gas token on Arc, send a plain value transfer to payTo and replay the hash in X-PAYMENT-ARC. Finality is instant on inclusion.",
      "version": "2",
      "replayHeader": "X-PAYMENT-ARC",
      "credentialTypes": [
        "authorization"
      ]
    },
    "payTo": "0xd334ab5151c624cada654854e2879903dc4217ed",
    "amount": "20000",
    "scheme": "exact",
    "network": "eip155:5042",
    "maxTimeoutSeconds": 300
  },
  {
    "asset": "0x3600000000000000000000000000000000000000",
    "extra": {
      "name": "GatewayWalletBatched",
      "note": "Circle Gateway nanopayment: pay from your Gateway balance with a gas-free signature (validBefore at least 7 days out). Settled by Circle in batches.",
      "version": "1",
      "verifyingContract": "0x77777777dcc4d5a8b6e418fd04d8997ef11000ee"
    },
    "payTo": "0xd334ab5151c624cada654854e2879903dc4217ed",
    "amount": "20000",
    "scheme": "exact",
    "network": "eip155:5042",
    "maxTimeoutSeconds": 604900
  },
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "GatewayWalletBatched",
      "note": "Circle Gateway nanopayment: pay from your Gateway balance with a gas-free signature (validBefore at least 7 days out). Settled by Circle in batches.",
      "version": "1",
      "verifyingContract": "0x77777777dcc4d5a8b6e418fd04d8997ef11000ee"
    },
    "payTo": "0xd334ab5151c624cada654854e2879903dc4217ed",
    "amount": "20000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 604900
  },
  {
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "extra": {
      "feePayer": "D93NE2kMj88BPsHfdZZ4A1HX2CGo14Y18Bdb3J4qtD5c"
    },
    "payTo": "HYiepS7mNCVVKoaDmZLQ6rNtMWHTQqKheM1NLGn1x8kJ",
    "amount": "20000",
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "maxTimeoutSeconds": 300
  },
  {
    "asset": "0x8d0D000Ee44948FC98c9B98A4FA4921476f08B0d",
    "extra": {
      "name": "World Liberty Financial USD",
      "note": "BNB Smart Chain: sign an EIP-3009 transferWithAuthorization in USD1 (18 decimals, EIP-712 name \"World Liberty Financial USD\", version \"1\") to payTo and send it base64 in PAYMENT-SIGNATURE; we settle it and pay the gas. Minimum $0.01 on BNB.",
      "minUsd": 0.01,
      "symbol": "USD1",
      "version": "1",
      "decimals": 18,
      "credentialTypes": [
        "authorization"
      ]
    },
    "payTo": "0xd334AB5151C624cAdA654854E2879903Dc4217eD",
    "amount": "20000000000000000",
    "scheme": "exact",
    "network": "eip155:56",
    "maxTimeoutSeconds": 300
  },
  {
    "asset": "0xcE24439F2D9C6a2289F741120FE202248B666666",
    "extra": {
      "name": "United Stables",
      "note": "BNB Smart Chain: sign an EIP-3009 transferWithAuthorization in U (18 decimals, EIP-712 name \"United Stables\", version \"1\") to payTo and send it base64 in PAYMENT-SIGNATURE; we settle it and pay the gas. Minimum $0.01 on BNB.",
      "minUsd": 0.01,
      "symbol": "U",
      "version": "1",
      "decimals": 18,
      "credentialTypes": [
        "authorization"
      ]
    },
    "payTo": "0xd334AB5151C624cAdA654854E2879903Dc4217eD",
    "amount": "20000000000000000",
    "scheme": "exact",
    "network": "eip155:56",
    "maxTimeoutSeconds": 300
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "type": "http",
        "method": "GET",
        "queryParams": {
          "q": "What is the cheapest way for an agent to get USDC on Arc?"
        },
        "discoverable": true
      },
      "output": {
        "type": "json",
        "schema": {
          "type": "object",
          "properties": {
            "ok": {
              "type": "boolean"
            },
            "data": {
              "type": "object"
            },
            "paid": {
              "type": "number"
            }
          }
        },
        "example": {
          "ok": true,
          "data": {},
          "paid": 0.02
        }
      }
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method",
            "queryParams"
          ],
          "properties": {
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "enum": [
                "GET"
              ],
              "type": "string"
            },
            "queryParams": {
              "type": "object",
              "required": [
                "q"
              ],
              "properties": {
                "q": {
                  "type": "string",
                  "maxLength": 600,
                  "minLength": 3,
                  "description": "Your question, 3 to 600 characters."
                }
              }
            }
          }
        },
        "output": {
          "type": "object"
        }
      }
    }
  }
}

Provenance

Seen in the source catalog
2026-10-14 09:21Z
Last indexed by Roundhouse
2026-10-19 12:30Z
Last enriched (probe, favicon, geo)
2026-10-14 10:16Z
x402 version
2
Max timeout
300s
Liveness probe
HTTP 402
Report

Hand this page to an agent

Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.

GET api.roundhouseai.io/v0/endpoints

This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 7 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.

Open skill.md
Show the prompt
Using Roundhouse, look up the x402 service Ask an AI agent on Arc a questio and tell me whether it is
worth paying: what a call costs, whether the endpoint answered when last probed, and what
its payment record actually shows.

curl -s 'https://api.roundhouseai.io/v0/endpoints?q=Ask%20an%20AI%20agent%20on%20Arc%20a%20questio'
curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>'

Then call it: read the price from the live 402 at https://apexfaucet.xyz/api/x402/ask-flux, never from
a cached figure, and pay with an x402 client.

The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except
/v0/unified* and /v0/endpoints. Either pay over x402 (mint a personal key for $0.01 at
GET https://api.roundhouseai.io/v0/test/x402), or ask me for an organization key, which I create at
https://roundhouseai.io/dashboard/connections. If you have neither, ask before going further.

If you do not have Roundhouse tools or skills installed, read
https://roundhouseai.io/skill.md first — it is the whole procedure.