Roundhouse

txpreflight

Base agent toolbox. /preflight simulates a tx (revert reason, gas, EIP-1559 fees in ETH and USD) before you sign. /verify reads a receipt and proves a USDC transfer settled: confirmations, amount, sender, recipient.

OtherUnknowneip155:8453Exactvia cdp
https://api.firstmention.uk/s/txpreflight/verify
BaseUsdcSettlementx402Gas
Settlements · 30d
4
No per-endpoint history for this service yet, so this is payments indexed to its PROVIDER's wallet over 30 days.
$0.04
Verified settled volume
4 settlements proven x402 by their on-chain EIP-3009 marker.
$0.010
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 2026-10-26 05:50Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0xe029Fcf4ba573F6fdc282208fe855dF8CBb3Ca9A

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

Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Provider
Coming soonledgerERC-8004

Accepts

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

0.01USDC≈ $0.01 USD
on Base · exact scheme

Pay 0.01 USDC on Base to 0xe029…3Ca9A. The signed payment is good for 5 minutes.

Paid to
0xe029…3Ca9A
USD Coin contract
0x8335…02913
Payment window
5 minutes
As published
10000 smallest units
The catalog’s raw entry
[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2"
    },
    "payTo": "0xe029Fcf4ba573F6fdc282208fe855dF8CBb3Ca9A",
    "amount": "10000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 300
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "type": "http",
        "method": "GET",
        "queryParams": {
          "tx": "0x54002146b9c089ad89c91d1750b45d0c35e133caa5b0a536df8f57e9c2a4a74b",
          "pay_to": "0xe029fcf4ba573f6fdc282208fe855df8cbb3ca9a",
          "amount_usd": 5
        }
      },
      "output": {
        "type": "json",
        "example": {
          "ok": true,
          "block": 53042026,
          "chain": "base",
          "check": {
            "asset": "USDC",
            "amountMet": true,
            "recipientMet": true
          },
          "status": "success",
          "verdict": "settled",
          "confirmations": 27804
        }
      }
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method"
          ],
          "properties": {
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "enum": [
                "GET",
                "HEAD",
                "DELETE"
              ],
              "type": "string"
            },
            "headers": {
              "type": "object",
              "additionalProperties": {
                "type": "string"
              }
            },
            "queryParams": {
              "type": "object",
              "properties": {
                "tx": {
                  "type": "string",
                  "description": "Transaction hash, 0x + 64 hex"
                },
                "asset": {
                  "type": "string",
                  "description": "/verify: ERC-20 to check (default USDC on Base)"
                },
                "pay_to": {
                  "type": "string",
                  "description": "/verify: require this recipient"
                },
                "pay_from": {
                  "type": "string",
                  "description": "/verify: require this sender"
                },
                "amount_usd": {
                  "type": "number",
                  "description": "/verify: minimum USD that must have transferred"
                }
              }
            }
          },
          "additionalProperties": false
        },
        "output": {
          "type": "object",
          "required": [
            "type"
          ],
          "properties": {
            "type": {
              "type": "string"
            },
            "example": {
              "type": "object",
              "properties": {
                "ok": {
                  "type": "boolean"
                },
                "block": {
                  "type": "number"
                },
                "chain": {
                  "type": "string"
                },
                "check": {
                  "type": "object",
                  "properties": {
                    "asset": {
                      "type": "string"
                    },
                    "amountMet": {
                      "type": "boolean"
                    },
                    "recipientMet": {
                      "type": "boolean"
                    }
                  }
                },
                "status": {
                  "type": "string"
                },
                "verdict": {
                  "type": "string"
                },
                "confirmations": {
                  "type": "number"
                }
              }
            }
          }
        }
      }
    }
  }
}

Provenance

Seen in the source catalog
2026-10-26 05:50Z
Last indexed by Roundhouse
2026-10-26 20:00Z
Last enriched (probe, favicon, geo)
—
x402 version
2
Max timeout
300s
Liveness probe
Not probed
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

No per-endpoint history for this service yet, so this is payments indexed to its PROVIDER's wallet over 30 days. 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 txpreflight 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=txpreflight'
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://api.firstmention.uk/s/txpreflight/verify, 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.