Roundhouse

saylorinnovations.com

Custom website design, hosting, automation and AI integration for small businesses nationwide. Most builds live in 3 weeks.

OtherLiveeip155:8453Exactvia facilitator:thirdweb
https://saylorinnovations.com/api/explorer/balance
Calls · 30d
2
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 5 snapshots so far.
$14.11
Verified settled volume
1,492 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.
—
Calls · 30d
Upstream's own call count for this endpoint, not ours.
—
Unique payers · 30d
Never called
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa

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.

Live 402 challenge

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

{
  "error": "Payment required to access this resource.",
  "accepts": [
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "memo": "saylor:datadesk:explorer-balance",
        "name": "USD Coin",
        "note": "Base settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
        "version": "2",
        "facilitatorOnly": true,
        "assetTransferMethod": "eip3009"
      },
      "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
      "amount": "10000",
      "scheme": "exact",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 120
    },
    {
      "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
      "extra": {
        "memo": "saylor:datadesk:explorer-balance",
        "name": "USD Coin",
        "note": "Polygon settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
        "version": "2",
        "facilitatorOnly": true,
        "assetTransferMethod": "eip3009"
      },
      "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
      "amount": "10000",
      "scheme": "exact",
      "network": "eip155:137",
      "maxTimeoutSeconds": 120
    },
    {
      "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
      "extra": {
        "memo": "saylor:datadesk:explorer-balance",
        "name": "USD Coin",
        "note": "Arbitrum settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
        "version": "2",
        "facilitatorOnly": true,
        "assetTransferMethod": "eip3009"
      },
      "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
      "amount": "10000",
      "scheme": "exact",
      "network": "eip155:42161",
      "maxTimeoutSeconds": 120
    },
    {
      "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
      "extra": {
        "memo": "saylor:datadesk:explorer-balance",
        "session": "eyJhcnRpY2xlSWQiOiJkYXRhZGVzazpleHBsb3Jlci1iYWxhbmNlIiwicmVmZXJlbmNlIjoiRXRnREJ2aHRKTjhiS25uWUEyNm1reGNrOWtmSkhmWFE1R1Q3bWhMZnNFNDMiLCJyZWNpcGllbnQiOiI3TFNqZnJKZjhmTnNCOFZBOXU3TjNXRW4yNXNtUUxwb2IzU3Z5VXZYYWN5NyIsIm1pbnQiOiJFUGpGV2RkNUF1ZnFTU3FlTTJxTjF4enliYXBDOEc0d0VHR2tad3lURHQxdiIsIm1pbkFtb3VudCI6MTAwMDAsImV4cCI6MTc5MjgwMTA3ODA1OX0.yS2y3YVf3IbQGPrx0KB5juZW5khFWk9Gvtg2kJRh1U0",
        "feePayer": "Hc3sdEAsCGQcpgfivywog9uwtk8gUBUZgsxdME1EJy88",
        "reference": "EtgDBvhtJN8bKnnYA26mkxck9kfJHfXQ5GT7mhLfsE43"
      },
      "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
      "amount": "10000",
      "scheme": "exact",
      "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
      "maxTimeoutSeconds": 120
    },
    {
      "asset": "Es9vMFrzaCERmJfrF4H2FYD4KCoNkY11McCe8BenwNYB",
      "extra": {
        "memo": "saylor:datadesk:explorer-balance",
        "session": "eyJhcnRpY2xlSWQiOiJkYXRhZGVzazpleHBsb3Jlci1iYWxhbmNlIiwicmVmZXJlbmNlIjoiMkF4Sk5KdVVTaVVDWGs2VHV5ZUhVS3h0VEZkVkM0cW91azNnMlo2UUpzR0ciLCJyZWNpcGllbnQiOiI3TFNqZnJKZjhmTnNCOFZBOXU3TjNXRW4yNXNtUUxwb2IzU3Z5VXZYYWN5NyIsIm1pbnQiOiJFczl2TUZyemFDRVJtSmZyRjRIMkZZRDRLQ29Oa1kxMU1jQ2U4QmVud05ZQiIsIm1pbkFtb3VudCI6MTAwMDAsImV4cCI6MTc5MjgwMTA3ODA1OX0.BM_rJriPHE0cJ4JME8r9ADcjFsL8pcnZdffFpeiYbuE",
        "feePayer": "Hc3sdEAsCGQcpgfivywog9uwtk8gUBUZgsxdME1EJy88",
        "reference": "2AxJNJuUSiUCXk6TuyeHUKxtTFdVC4qouk3g2Z6QJsGG"
      },
      "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
      "amount": "10000",
      "scheme": "exact",
      "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
      "maxTimeoutSeconds": 120
    },
    {
      "asset": "So11111111111111111111111111111111111111112",
      "extra": {
        "memo": "saylor:datadesk:explorer-balance",
        "note": "Native SOL: send lamports with a system transfer, not an SPL transfer. Price is quoted live and this quote expires in 120s.",
        "native": true,
        "session": "eyJhcnRpY2xlSWQiOiJkYXRhZGVzazpleHBsb3Jlci1iYWxhbmNlIiwicmVmZXJlbmNlIjoiQTNVR3RTSHdEc0p5c0tBdzRLUnZ2UWVmajJWSzdMdjlWR2lLRWJ1bnU0MnAiLCJyZWNpcGllbnQiOiI3TFNqZnJKZjhmTnNCOFZBOXU3TjNXRW4yNXNtUUxwb2IzU3Z5VXZYYWN5NyIsIm1pbnQiOm51bGwsIm1pbkFtb3VudCI6OTQ2MTQsImV4cCI6MTc5MjgwMTA3ODA1OX0.4FWjlWbIhgUPKW_arlJ11vde9vfsSBaZVTMvSno6VIw",
        "reference": "A3UGtSHwDsJysKAw4KRvvQefj2VK7Lv9VGiKEbunu42p",
        "solUsdPrice": 102.52,
        "quotedLamports": "97541"
      },
      "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
      "amount": "94614",
      "scheme": "exact",
      "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
      "maxTimeoutSeconds": 120
    }
  ],
  "resource": {
    "url": "https://saylorinnovations.com/api/explorer/balance?chain=ethereum&address=0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
    "tags": [
      "wallet balance",
      "erc20 token balance",
      "address balance lookup",
      "account type check",
      "evm address explorer"
    ],
    "iconUrl": "https://saylorinnovations.com/og-image.jpg",
    "mimeType": "application/json",
    "description": "EVM address balance on 16 chains: native coin, main stablecoins or chosen ERC-20s, nonce, and whether it is a plain account, a contract or an EIP-7702 delegate.",
    "serviceName": "Saylor Innovations Data Desk"
  },
  "extensions": {
    "tags": [
      "wallet balance",
      "erc20 token balance",
      "address balance lookup",
      "account type check",
      "evm address explorer"
    ],
    "bazaar": {
      "info": {
        "input": {
          "type": "http",
          "method": "GET",
          "queryParams": {
            "chain": "ethereum",
            "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
          }
        },
        "output": {
          "type": "json",
          "example": {
            "note": "Read straight from chain RPC at the latest block. Without tokens=, the chain's main stablecoins and wrapped native token are checked; pass tokens= (up to 10 contract addresses) for others. transaction_count is the nonce: transactions sent by this address, not received. No USD values: this route is chain data only.",
            "chain": "ethereum",
            "source": "Chain JSON-RPC (ethereum)",
            "tokens": [
              {
                "label": "USDC",
                "token": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
                "symbol": "USDC",
                "balance": "37.192124",
                "decimals": 6,
                "balance_base_units": "37192124"
              },
              {
                "label": "USDT",
                "token": "0xdAC17F958D2ee523a2206206994597C13D831ec7",
                "symbol": "USDT",
                "balance": "291.368219",
                "decimals": 6,
                "balance_base_units": "291368219"
              },
              {
                "label": "DAI",
                "token": "0x6B175474E89094C44Da98b954EedeAC495271d0F",
                "symbol": "DAI",
                "balance": "14.37207827332311288",
                "decimals": 18,
                "balance_base_units": "14372078273323112880"
              },
              {
                "label": "WETH",
                "token": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
                "symbol": "WETH",
                "balance": "1.46652803708515807",
                "decimals": 18,
                "balance_base_units": "1466528037085158070"
              }
            ],
            "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
            "chain_id": 1,
            "balance_wei": "5773251986299759339",
            "account_kind": "eip7702_delegated_account",
            "block_number": 26234798,
            "native_symbol": "ETH",
            "balance_native": 5.773251986299759,
            "code_size_bytes": 23,
            "eip7702_delegate": "0x5A7FC11397E9a8AD41BF10bf13F22B0a63f96f6d",
            "transaction_count": 5969
          }
        }
      },
      "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": [
                  "chain",
                  "address"
                ],
                "properties": {
                  "chain": {
                    "type": "string",
                    "description": "chain name or id"
                  },
                  "address": {
                    "type": "string",
                    "description": "the 0x account or contract address"
                  }
                }
              }
            },
            "additionalProperties": false
          },
          "output": {
            "type": "object",
            "required": [
              "type"
            ],
            "properties": {
              "type": {
                "type": "string",
                "const": "json"
              },
              "example": {
                "type": "object",
                "required": [
                  "chain",
                  "chain_id",
                  "address",
                  "account_kind",
                  "balance_wei",
                  "balance_native",
                  "native_symbol",
                  "transaction_count",
                  "tokens",
                  "note",
                  "source"
                ],
                "properties": {
                  "note": {
                    "type": "string",
                    "description": "Caveat or context for reading the result"
                  },
                  "chain": {
                    "type": "string",
                    "description": "Blockchain the data is for"
                  },
                  "source": {
                    "type": "string",
                    "description": "Data source the values come from"
                  },
                  "tokens": {
                    "type": "array",
                    "description": "Token balances or token records"
                  },
                  "address": {
                    "type": "string",
                    "description": "Account or contract address"
                  },
                  "chain_id": {
                    "type": "number",
                    "description": "EVM chain id"
                  },
                  "balance_wei": {
                    "type": "string",
                    "description": "Balance wei"
                  },
                  "account_kind": {
                    "type": "string",
                    "description": "Account kind"
                  },
                  "block_number": {
                    "type": "number",
                    "description": "Block number"
                  },
                  "native_symbol": {
                    "type": "string",
                    "description": "Native symbol"
                  },
                  "balance_native": {
                    "type": "number",
                    "description": "Balance native"
                  },
                  "code_size_bytes": {
                    "type": "number",
                    "description": "Code size, in bytes"
                  },
                  "eip7702_delegate": {
                    "type": [
                      "string",
                      "null"
                    ],
                    "description": "Delegate contract address when the account uses an EIP-7702 delegation, otherwise null"
                  },
                  "transaction_count": {
                    "type": "number",
                    "description": "Number of transaction"
                  }
                }
              }
            }
          }
        }
      }
    },
    "method": "GET",
    "example": {
      "note": "Read straight from chain RPC at the latest block. Without tokens=, the chain's main stablecoins and wrapped native token are checked; pass tokens= (up to 10 contract addresses) for others. transaction_count is the nonce: transactions sent by this address, not received. No USD values: this route is chain data only.",
      "chain": "ethereum",
      "source": "Chain JSON-RPC (ethereum)",
      "tokens": [
        {
          "label": "USDC",
          "token": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
          "symbol": "USDC",
          "balance": "37.192124",
          "decimals": 6,
          "balance_base_units": "37192124"
        },
        {
          "label": "USDT",
          "token": "0xdAC17F958D2ee523a2206206994597C13D831ec7",
          "symbol": "USDT",
          "balance": "291.368219",
          "decimals": 6,
          "balance_base_units": "291368219"
        },
        {
          "label": "DAI",
          "token": "0x6B175474E89094C44Da98b954EedeAC495271d0F",
          "symbol": "DAI",
          "balance": "14.37207827332311288",
          "decimals": 18,
          "balance_base_units": "14372078273323112880"
        },
        {
          "label": "WETH",
          "token": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
          "symbol": "WETH",
          "balance": "1.46652803708515807",
          "decimals": 18,
          "balance_base_units": "1466528037085158070"
        }
      ],
      "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
      "chain_id": 1,
      "balance_wei": "5773251986299759339",
      "account_kind": "eip7702_delegated_account",
      "block_number": 26234798,
      "native_symbol": "ETH",
      "balance_native": 5.773251986299759,
      "code_size_bytes": 23,
      "eip7702_delegate": "0x5A7FC11397E9a8AD41BF10bf13F22B0a63f96f6d",
      "transaction_count": 5969
    },
    "license": "LicenseRef-Saylor-Agent-Use-1.0",
    "mimeType": "application/json",
    "freshness": "fetched live (cached up to 1 hour for large reference files)",
    "tokenCount": null,
    "inputSchema": {
      "chain": "chain name or id",
      "tokens": "optional: up to 10 comma-separated ERC-20 contract addresses; default is the chain main stablecoins",
      "address": "the 0x account or contract address"
    },
    "serviceName": "Saylor Innovations Data Desk",
    "instructions": "STANDARD PATH (works with stock x402 clients): send payload.transaction — a base64 partially-signed Solana transaction — and we route verify/settle through an x402 facilitator that sponsors the fee and submits it. Include the chosen accepts entry as \"accepted\" so we can match terms. ALTERNATIVE PATH (no facilitator): Pick ONE entry from accepts and use the reference and session from THAT entry — each asset has its own. USDC or USDT: send an SPL transfer of the exact amount. Native SOL (asset=So11111111111111111111111111111111111111112, extra.native=true): send that many lamports with a system transfer. Either way include extra.reference as a read-only account (Solana Pay style), then retry with PAYMENT-SIGNATURE: base64({x402Version:2, payload:{session, reference}}). If your client cannot attach a reference, send payload.signature instead (USDC only). SOL amounts are quoted live and expire in 120s; stablecoins do not move. The facilitator path verifies and settles in this request. Only the alternative self-submitted Solana path needs retries while the transfer is indexed (typically 3-4 attempts over 10-20s). On that path, a 402 saying \"payment not found on-chain yet\" means keep retrying.",
    "outputSchema": {
      "type": "object",
      "required": [
        "chain",
        "chain_id",
        "address",
        "account_kind",
        "balance_wei",
        "balance_native",
        "native_symbol",
        "transaction_count",
        "tokens",
        "note",
        "source"
      ],
      "properties": {
        "note": {
          "type": "string"
        },
        "chain": {
          "type": "string"
        },
        "source": {
          "type": "string"
        },
        "tokens": {
          "type": "array"
        },
        "address": {
          "type": "string"
        },
        "chain_id": {
          "type": "number"
        },
        "balance_wei": {
          "type": "string"
        },
        "account_kind": {
          "type": "string"
        },
        "block_number": {
          "type": "number"
        },
        "native_symbol": {
          "type": "string"
        },
        "balance_native": {
          "type": "number"
        },
        "code_size_bytes": {
          "type": "number"
        },
        "eip7702_delegate": {
          "type": [
            "string",
            "null"
          ]
        },
        "transaction_count": {
          "type": "number"
        }
      }
    },
    "noPathTemplate": true,
    "settlementModes": [
      "facilitator-transaction",
      "self-submitted-reference"
    ],
    "typicalLatencyMs": 700
  },
  "x402Version": 2
}

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 0xA2A8…fc8aa. The signed payment is good for 2 minutes.

Paid to
0xA2A8…fc8aa
USD Coin contract
0x8335…02913
Payment window
2 minutes
As published
10000 smallest units
Returns
application/json
10000units
on Polygon · 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
0xA2A8…fc8aa
Token contract
0x3c49…c3359
Payment window
2 minutes
Returns
application/json
10000units
on Arbitrum · 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
0xA2A8…fc8aa
Token contract
0xaf88…e5831
Payment window
2 minutes
Returns
application/json
10000units
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
7LSjfr…Xacy7
Token contract
EPjFWd…TDt1v
Payment window
2 minutes
Returns
application/json
10000units
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
7LSjfr…Xacy7
Token contract
Es9vMF…nwNYB
Payment window
2 minutes
Returns
application/json
91466units
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
7LSjfr…Xacy7
Token contract
So1111…11112
Payment window
2 minutes
Returns
application/json
The catalog’s raw entry
[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
    "scheme": "exact",
    "network": "eip155:8453",
    "mimeType": "application/json",
    "resource": "https://saylorinnovations.com/api/explorer/balance",
    "description": "",
    "maxAmountRequired": "10000",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
    "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
    "scheme": "exact",
    "network": "eip155:137",
    "mimeType": "application/json",
    "resource": "https://saylorinnovations.com/api/explorer/balance",
    "description": "",
    "maxAmountRequired": "10000",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
    "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
    "scheme": "exact",
    "network": "eip155:42161",
    "mimeType": "application/json",
    "resource": "https://saylorinnovations.com/api/explorer/balance",
    "description": "",
    "maxAmountRequired": "10000",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "mimeType": "application/json",
    "resource": "https://saylorinnovations.com/api/explorer/balance",
    "description": "",
    "maxAmountRequired": "10000",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "Es9vMFrzaCERmJfrF4H2FYD4KCoNkY11McCe8BenwNYB",
    "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "mimeType": "application/json",
    "resource": "https://saylorinnovations.com/api/explorer/balance",
    "description": "",
    "maxAmountRequired": "10000",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "So11111111111111111111111111111111111111112",
    "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "mimeType": "application/json",
    "resource": "https://saylorinnovations.com/api/explorer/balance",
    "description": "",
    "maxAmountRequired": "91466",
    "maxTimeoutSeconds": 120
  }
]

Provenance

Seen in the source catalog
2026-10-21 03:13Z
Last indexed by Roundhouse
2026-10-23 23:45Z
Last enriched (probe, favicon, geo)
2026-10-24 00:15Z
x402 version
1
Max timeout
120s
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. 5 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 saylorinnovations.com 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=saylorinnovations.com'
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://saylorinnovations.com/api/explorer/balance, 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.