Roundhouse

www.surplusintelligence.ai

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InferenceLiveeip155:8453Exactvia cdp
https://www.surplusintelligence.ai/x402/api/inference/v1/chat/completions
Settlements · 30d
3,282
No per-endpoint history for this service yet, so this is payments indexed to its PROVIDER's wallet over 30 days.
$1,210.87
Verified settled volume
2,908 settlements proven x402 by their on-chain EIP-3009 marker.
$0.0033
Listed price
As published in the catalog. Always read the live 402 before paying.
140
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-06-08 15:36Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x8581784D3E598cCa3482375CFF2409Ac9DD8c402

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.

{
  "mpp": {
    "supported": true,
    "instructions": "Use Authorization: Payment header with Tempo wallet credential"
  },
  "x402": {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "model": "llama-3.3-70b-instruct",
    "payTo": "0x8581784D3E598cCa3482375CFF2409Ac9DD8c402",
    "amount": "3301",
    "network": "base",
    "version": 2,
    "currency": "USDC",
    "facilitator": "https://api.cdp.coinbase.com/platform/v2/x402",
    "instructions": [
      "Preferred: Use the upto scheme (Permit2) — you authorize a max but only pay for actual usage.",
      "Fallback: Use exact scheme (EIP-3009) — you are pre-charged based on max_tokens.",
      "x402 includes a per-request fee to compensate facilitation costs. For cheapest inference, use SIWE + one-time USDC approval from surplusintelligence.ai website.",
      "Sign an x402 payment for the amount specified.",
      "Include the signed payload in the PAYMENT-SIGNATURE header (base64-encoded).",
      "Resend the same request with the payment header attached."
    ],
    "x402FlatFeeUsd": "0.003000",
    "estimatedCostUsd": "0.003300"
  },
  "error": {
    "code": "x402_payment_required",
    "type": "payment_required",
    "message": "Payment required for inference"
  },
  "notice": "x402 includes a per-request fee to compensate facilitation costs. For cheapest inference, use SIWE + one-time USDC approval from surplusintelligence.ai website.",
  "accepts": [
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2"
      },
      "payTo": "0x8581784D3E598cCa3482375CFF2409Ac9DD8c402",
      "amount": "3301",
      "scheme": "exact",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 120
    },
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2",
        "facilitatorAddress": "0x4c934c63C786157Fefd990945b25eA60a0FB0205"
      },
      "payTo": "0x8581784D3E598cCa3482375CFF2409Ac9DD8c402",
      "amount": "3301",
      "scheme": "upto",
      "network": "eip155:8453",
      "maxTimeoutSeconds": 120
    }
  ],
  "resource": {
    "url": "https://www.surplusintelligence.ai/x402/api/inference/v1/chat/completions",
    "mimeType": "application/json",
    "description": "Get OpenAI-compatible inference from many models at market prices via Surplus Intelligence."
  },
  "extensions": {
    "bazaar": {
      "info": {
        "input": {
          "body": {
            "model": "llama-3.3-70b",
            "messages": [
              {
                "role": "user",
                "content": "Say hello from Surplus Intelligence."
              }
            ],
            "max_tokens": 16
          },
          "type": "http",
          "method": "POST",
          "bodyType": "json"
        },
        "output": {
          "type": "json",
          "example": {
            "id": "chatcmpl_surplus_example",
            "usage": {
              "total_tokens": 18,
              "prompt_tokens": 12,
              "completion_tokens": 6
            },
            "object": "chat.completion",
            "choices": [
              {
                "index": 0,
                "message": {
                  "role": "assistant",
                  "content": "Hello from Surplus Intelligence."
                },
                "finish_reason": "stop"
              }
            ]
          }
        }
      },
      "schema": {
        "type": "object",
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "required": [
          "input"
        ],
        "properties": {
          "input": {
            "type": "object",
            "required": [
              "type",
              "method",
              "bodyType",
              "body"
            ],
            "properties": {
              "body": {
                "required": [
                  "model",
                  "messages"
                ],
                "properties": {
                  "model": {
                    "type": "string",
                    "description": "Surplus Intelligence model id. Call /x402/api/inference/v1/models for available models."
                  },
                  "stream": {
                    "type": "boolean"
                  },
                  "messages": {
                    "type": "array",
                    "items": {
                      "type": "object",
                      "required": [
                        "role",
                        "content"
                      ],
                      "properties": {
                        "role": {
                          "enum": [
                            "system",
                            "developer",
                            "user",
                            "assistant",
                            "tool"
                          ],
                          "type": "string"
                        },
                        "content": {}
                      },
                      "additionalProperties": true
                    },
                    "minItems": 1,
                    "description": "OpenAI-compatible chat messages."
                  },
                  "max_tokens": {
                    "type": "integer",
                    "minimum": 1,
                    "description": "Maximum output tokens."
                  },
                  "temperature": {
                    "type": "number",
                    "maximum": 2,
                    "minimum": 0
                  }
                },
                "additionalProperties": true
              },
              "type": {
                "type": "string",
                "const": "http"
              },
              "method": {
                "enum": [
                  "POST",
                  "PUT",
                  "PATCH"
                ],
                "type": "string"
              },
              "bodyType": {
                "enum": [
                  "json",
                  "form-data",
                  "text"
                ],
                "type": "string"
              }
            },
            "additionalProperties": false
          },
          "output": {
            "type": "object",
            "required": [
              "type"
            ],
            "properties": {
              "type": {
                "type": "string"
              },
              "example": {
                "type": "object",
                "required": [
                  "id",
                  "object",
                  "choices"
                ],
                "properties": {
                  "id": {
                    "type": "string"
                  },
                  "usage": {
                    "type": "object"
                  },
                  "object": {
                    "type": "string"
                  },
                  "choices": {
                    "type": "array"
                  }
                }
              }
            }
          }
        }
      }
    }
  },
  "x402Version": 2,
  "cheapestOption": {
    "method": "SIWE + one-time USDC approval",
    "reason": "Uses the native Surplus Intelligence settlement flow instead of per-request x402 facilitation."
  }
}

Accepts

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

0.003302USDC≈ $0.003302 USD
on Base · exact scheme

Pay 0.003302 USDC on Base to 0x8581…8c402. The signed payment is good for 2 minutes.

Paid to
0x8581…8c402
USD Coin contract
0x8335…02913
Payment window
2 minutes
As published
3302 smallest units
0.003302USDC≈ $0.003302 USD
on Base · upto scheme

Pay 0.003302 USDC on Base to 0x8581…8c402. The signed payment is good for 2 minutes.

Paid to
0x8581…8c402
USD Coin contract
0x8335…02913
Payment window
2 minutes
As published
3302 smallest units
The catalog’s raw entry
[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2"
    },
    "payTo": "0x8581784D3E598cCa3482375CFF2409Ac9DD8c402",
    "amount": "3302",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2",
      "facilitatorAddress": "0x67B9CE703d9ce658d7C4ac3c289cEa112fE662Af"
    },
    "payTo": "0x8581784D3E598cCa3482375CFF2409Ac9DD8c402",
    "amount": "3302",
    "scheme": "upto",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 120
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "body": {
          "model": "llama-3.3-70b",
          "messages": [
            {
              "role": "user",
              "content": "Say hello from Surplus Intelligence."
            }
          ],
          "max_tokens": 16
        },
        "type": "http",
        "method": "POST",
        "bodyType": "json"
      },
      "output": {
        "type": "json",
        "example": {
          "id": "chatcmpl_surplus_example",
          "usage": {
            "total_tokens": 18,
            "prompt_tokens": 12,
            "completion_tokens": 6
          },
          "object": "chat.completion",
          "choices": [
            {
              "index": 0,
              "message": {
                "role": "assistant",
                "content": "Hello from Surplus Intelligence."
              },
              "finish_reason": "stop"
            }
          ]
        }
      }
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method",
            "bodyType",
            "body"
          ],
          "properties": {
            "body": {
              "required": [
                "model",
                "messages"
              ],
              "properties": {
                "model": {
                  "type": "string",
                  "description": "Surplus Intelligence model id. Call /x402/api/inference/v1/models for available models."
                },
                "stream": {
                  "type": "boolean"
                },
                "messages": {
                  "type": "array",
                  "items": {
                    "type": "object",
                    "required": [
                      "role",
                      "content"
                    ],
                    "properties": {
                      "role": {
                        "enum": [
                          "system",
                          "developer",
                          "user",
                          "assistant",
                          "tool"
                        ],
                        "type": "string"
                      },
                      "content": {}
                    },
                    "additionalProperties": true
                  },
                  "minItems": 1,
                  "description": "OpenAI-compatible chat messages."
                },
                "max_tokens": {
                  "type": "integer",
                  "minimum": 1,
                  "description": "Maximum output tokens."
                },
                "temperature": {
                  "type": "number",
                  "maximum": 2,
                  "minimum": 0
                }
              },
              "additionalProperties": true
            },
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "enum": [
                "POST",
                "PUT",
                "PATCH"
              ],
              "type": "string"
            },
            "bodyType": {
              "enum": [
                "json",
                "form-data",
                "text"
              ],
              "type": "string"
            }
          },
          "additionalProperties": false
        },
        "output": {
          "type": "object",
          "required": [
            "type"
          ],
          "properties": {
            "type": {
              "type": "string"
            },
            "example": {
              "type": "object",
              "required": [
                "id",
                "object",
                "choices"
              ],
              "properties": {
                "id": {
                  "type": "string"
                },
                "usage": {
                  "type": "object"
                },
                "object": {
                  "type": "string"
                },
                "choices": {
                  "type": "array"
                }
              }
            }
          }
        }
      }
    }
  }
}

Provenance

Seen in the source catalog
2026-06-08 15:36Z
Last indexed by Roundhouse
2026-07-08 03:00Z
Last enriched (probe, favicon, geo)
2026-09-20 21:45Z
x402 version
2
Max timeout
120s
Liveness probe
HTTP 404
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 www.surplusintelligence.ai 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=www.surplusintelligence.ai'
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://www.surplusintelligence.ai/x402/api/inference/v1/chat/completions, 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. Mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402,
or use an organization key from https://roundhouseai.io/dashboard/team.

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