Roundhouse

OP Mainnet Onchain Data

Whale and large-trade tracker for an ERC-20 on OP Mainnet: every buy and sell in the last N minutes on the token's deepest WETH/USDC pools (Uniswap v3 or Velodrome), with USD size, side, wallet and transaction for the largest trades, buy/sell volume and net flow, and the wallets that bought or sold the most.

TradingLiveeip155:8453Exactvia cdp
https://ca-tax-api-mainnet.lxtap.workers.dev/optimism/trades
OptimismOnchainerc20TokenWallet
Calls · 30d
1
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 4 snapshots so far.
$2.05
Verified settled volume
276 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 2026-10-22 21:56Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x2ECB9E1fcca7A62758c679F11bC3241466d181d8

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

Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Provider

The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.

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 0x2ECB…181d8. The signed payment is good for 5 minutes.

Paid to
0x2ECB…181d8
USD Coin contract
0x8335…02913
Payment window
5 minutes
As published
20000 smallest units
The catalog’s raw entry
[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2"
    },
    "payTo": "0x2ECB9E1fcca7A62758c679F11bC3241466d181d8",
    "amount": "20000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 300
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "type": "http",
        "method": "GET",
        "queryParams": {
          "token": "0x4200000000000000000000000000000000000042",
          "minUsd": "100",
          "minutes": "60"
        }
      },
      "output": {
        "type": "json",
        "example": {
          "chain": "optimism",
          "notes": "Trades from the 3 deepest WETH/USDC pools; other pairs and aggregator-internal routes are not counted. Wallets are transaction senders, looked up for the 40 largest trades.",
          "token": {
            "symbol": "OP",
            "address": "0x4200000000000000000000000000000000000042",
            "decimals": 18
          },
          "window": {
            "to": "2026-10-22T16:23:21.000Z",
            "from": "2026-10-22T15:23:21.000Z",
            "minutes": 60,
            "toBlock": 158543712,
            "fromBlock": 158541912
          },
          "summary": {
            "buys": 31,
            "sells": 10,
            "trades": 41,
            "netFlowUsd": 963.893,
            "buyVolumeUsd": 1464.88,
            "sellVolumeUsd": 500.992,
            "largestTradeUsd": 136.298
          },
          "nativeUsd": 2392.72,
          "topBuyers": [
            {
              "netUsd": 654.5,
              "trades": 6,
              "wallet": "0xF104e69537346E54BCbDB5a1280aE3Aeef092c5B",
              "soldUsd": 0,
              "boughtUsd": 654.5
            },
            {
              "netUsd": 164.6,
              "trades": 8,
              "wallet": "0x78126dAC3a2C08479d2196741Da77F56Ca8CFB88",
              "soldUsd": 29.98,
              "boughtUsd": 194.5
            },
            {
              "netUsd": 152.4,
              "trades": 6,
              "wallet": "0x042f093b5D3e35C3cFa891E461f165e2BDF3A4BC",
              "soldUsd": 49.23,
              "boughtUsd": 201.7
            },
            {
              "netUsd": 125.8,
              "trades": 1,
              "wallet": "0x092772CdEF109fEd26052E79B952Ac5404f1Ed21",
              "soldUsd": 0,
              "boughtUsd": 125.8
            },
            {
              "netUsd": 21.35,
              "trades": 1,
              "wallet": "0xf4c2BAA132722670CC0Eb89C8a9329eE8F2389ED",
              "soldUsd": 0,
              "boughtUsd": 21.35
            }
          ],
          "topSellers": [
            {
              "netUsd": -232.5,
              "trades": 2,
              "wallet": "0x31074ff71CE53897194028316A355F98F2043D88",
              "soldUsd": 232.5,
              "boughtUsd": 0
            },
            {
              "netUsd": -9.994,
              "trades": 1,
              "wallet": "0x6663F9524b76B547F1070E82ddE1Cc0A2236d758",
              "soldUsd": 9.994,
              "boughtUsd": 0
            }
          ],
          "largeTrades": [
            {
              "tx": "0x3abbe44d8a518056071465655f99749236a6038dc9bd74d13908020a2d916f08",
              "dex": "uniswap-v3",
              "usd": 136.298,
              "side": "sell",
              "block": 158542191,
              "wallet": "0x31074ff71CE53897194028316A355F98F2043D88",
              "approxTime": "2026-10-22T15:32:39.000Z",
              "quoteAmount": 0.056963409,
              "quoteSymbol": "WETH",
              "tokenAmount": 1146.4553
            },
            {
              "tx": "0x2f24b77a43957031dc2920de3d7053e2982c0e7d6f4dbac01ee987bdaeca0e97",
              "dex": "uniswap-v3",
              "usd": 125.834,
              "side": "buy",
              "block": 158542384,
              "wallet": "0x092772CdEF109fEd26052E79B952Ac5404f1Ed21",
              "approxTime": "2026-10-22T15:39:05.000Z",
              "quoteAmount": 0.052590179,
              "quoteSymbol": "WETH",
              "tokenAmount": 1051.44
            },
            {
              "tx": "0xd2e4ef821f04a1ccdde0e63b134ea69a36b846025b544f0903a736911d6af6a0",
              "dex": "uniswap-v3",
              "usd": 120.034,
              "side": "buy",
              "block": 158542226,
              "wallet": "0xF104e69537346E54BCbDB5a1280aE3Aeef092c5B",
              "approxTime": "2026-10-22T15:33:49.000Z",
              "quoteAmount": 0.050166382,
              "quoteSymbol": "WETH",
              "tokenAmount": 1003.3283
            },
            {
              "tx": "0x75489fd0b28be01ba509303315fbad4df8a447c0bbcde4e2d15641f5b7458f49",
              "dex": "uniswap-v3",
              "usd": 119.403,
              "side": "buy",
              "block": 158542217,
              "wallet": "0xF104e69537346E54BCbDB5a1280aE3Aeef092c5B",
              "approxTime": "2026-10-22T15:33:31.000Z",
              "quoteAmount": 0.049902608,
              "quoteSymbol": "WETH",
              "tokenAmount": 998.35308
            },
            {
              "tx": "0x5b717b635a7e6d7bfa095ed872b8a597a6feb87b176db2e8e32d3c5ae045dd1a",
              "dex": "uniswap-v3",
              "usd": 113.131,
              "side": "buy",
              "block": 158543036,
              "wallet": "0xF104e69537346E54BCbDB5a1280aE3Aeef092c5B",
              "approxTime": "2026-10-22T16:00:49.000Z",
              "quoteAmount": 0.047281406,
              "quoteSymbol": "WETH",
              "tokenAmount": 944.27912
            }
          ],
          "poolsScanned": [
            {
              "dex": "uniswap-v3",
              "pool": "0x68F5C0A2DE713a54991E01858Fd27a3832401849",
              "pairedWith": "WETH"
            },
            {
              "dex": "velodrome",
              "pool": "0xd25711EdfBf747efCE181442Cc1D8F5F8fc8a0D3",
              "pairedWith": "WETH"
            },
            {
              "dex": "uniswap-v3",
              "pool": "0xB533c12fB4e7b53b5524EAb9b47d93fF6C7A456F",
              "pairedWith": "USDC"
            }
          ]
        }
      }
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method"
          ],
          "properties": {
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "enum": [
                "GET"
              ],
              "type": "string"
            },
            "queryParams": {
              "type": "object",
              "required": [
                "token"
              ],
              "properties": {
                "limit": {
                  "type": "string",
                  "pattern": "^\\d{1,2}$",
                  "description": "Max trades listed, 1 to 40, default 20"
                },
                "token": {
                  "type": "string",
                  "pattern": "^0x[0-9a-fA-F]{40}$",
                  "description": "Token contract address on OP Mainnet"
                },
                "minUsd": {
                  "type": "string",
                  "pattern": "^\\d+(\\.\\d+)?$",
                  "description": "Only list trades at least this large in USD, default 1000"
                },
                "minutes": {
                  "type": "string",
                  "pattern": "^\\d{1,3}$",
                  "description": "Look-back window in minutes; 5 to 240, default 60 (capped at 12,000 blocks, about 50 minutes on Arbitrum)"
                }
              },
              "additionalProperties": false
            }
          },
          "additionalProperties": false
        },
        "output": {
          "type": "object",
          "required": [
            "type"
          ],
          "properties": {
            "type": {
              "type": "string"
            },
            "example": {
              "type": "object"
            }
          }
        }
      }
    }
  }
}

Provenance

Seen in the source catalog
2026-10-22 21:56Z
Last indexed by Roundhouse
2026-10-26 20:10Z
Last enriched (probe, favicon, geo)
2026-10-22 23:16Z
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. 4 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 OP Mainnet Onchain Data 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=OP%20Mainnet%20Onchain%20Data'
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://ca-tax-api-mainnet.lxtap.workers.dev/optimism/trades, 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.