Evidence row 124838

What was observed

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      "x402",
      "https://x402-agent-api.onrender.com/api/v1/hvac-duct-size"
    ]
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  "name": "Agent Utility Suite",
  "owner_address": "0x6847231bd28e16a0a57c59793f6b8bd8cc0043ac",
  "raw": {
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        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
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      }
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    "description": "HVAC duct sizing calculator: any two of duct size (round or rectangular), airflow, velocity and friction rate. Round and rectangular equivalents, nearest standard sizes, friction loss per 100 ft (Darcy-Weisbach, Colebrook), velocity pressure, design checks. Equal-friction sizing, fixed-depth ducts, IP or SI. Shows every step with the numbers. $0.002 USDC per call.",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "body": {
              "airflow": 1000,
              "friction_rate": 0.08
            },
            "bodyType": "json",
            "method": "POST",
            "type": "http"
          },
          "output": {
            "example": {
              "airflow": 1000,
              "checks": {
                "aspect_ratio": null,
                "friction": "Typical design range (0.04-0.15 in. w.g./100 ft; about 0.3-1.2 Pa/m).",
                "velocity": "Normal design range (400-2,500 FPM; about 2-12.7 m/s)."
              },
              "friction_factor": 0.01885,
              "friction_rate": 0.08,
              "inputs_used": {
                "airflow": 1000,
                "friction_rate": 0.08
              },
              "next_calls": [
                {
                  "arguments": {
                    "airflow": 1000,
                    "entering": {
                      "dry_bulb": 80,
                      "wet_bulb": 67
                    },
                    "leaving": {
                      "dry_bulb": 55,
                      "wet_bulb": 54
                    },
                    "units": "IP"
                  },
                  "price": "$0.002",
                  "tool": "hvac_coil_load",
                  "why": "What cooling load does 1000 CFM carry from 80/67 to 55/54 °F?"
                }
              ],
              "notes": [
                "The rectangular size has the same friction loss and airflow as the round duct (ASHRAE equivalent diameter); its velocity is lower because its area is larger.",
                "Galvanized steel (ε = 0.0003 ft) and standard air (0.075 lb/ft³, 70 °F, sea level). Fittings and transitions are not included.",
                "For design guidance; the engineer of record is responsible for final selections."
              ],
              "primary_shape": "round",
              "rectangular": {
                "area": 1.184,
                "aspect_ratio": 1,
                "basis": "equal_friction",
                "equivalent_diameter": 14.27,
                "friction_rate": 0.08,
                "height": 13.06,
                "standard_sizes": [
                  {
                    "aspect_ratio": 1,
                    "best_fit": false,
                    "equivalent_diameter": 15.3,
                    "friction_rate": 0.0568,
                    "height": 14,
                    "velocity": 735,
                    "width": 14
                  },
                  {
                    "aspect_ratio": 1.33,
                    "best_fit": false,
                    "equivalent_diameter": 15.11,
                    "friction_rate": 0.0605,
                    "height": 12,
                    "velocity": 750,
                    "width": 16
                  }
                ],
                "velocity": 845,
                "width": 13.06
              },
              "references": [
                "ASHRAE Handbook—Fundamentals (2021), Ch. 21 Duct Design",
                "SMACNA HVAC Duct Design Manual (standard sizes, aspect ratio guidance)"
              ],
              "reynolds_number": 114361,
              "round": {
                "area": 1.1112,
                "diameter": 14.27,
                "friction_rate": 0.08,
                "standard_sizes": [
                  {
                    "best_fit": true,
                    "diameter": 14,
                    "friction_rate": 0.088,
                    "velocity": 935
                  },
                  {
                    "best_fit": false,
                    "diameter": 16,
                    "friction_rate": 0.0457,
                    "velocity": 716
                  }
                ],
                "velocity": 900
              },
              "solved_for": "size",
              "steps": [
                {
                  "calculation": "Iterated the diameter (bisection) until the Darcy-Weisbach friction loss at 1,000 CFM equals 0.0800 in. w.g./100 ft → D = 14.27 in",
                  "reference": "ASHRAE Handbook—Fundamentals (2021), Ch. 21 Duct Design",
                  "step": "Round diameter at the friction rate (equal friction)"
                },
                {
                  "calculation": "For W = H = S: De = 1.30·S^1.25 / (2S)^0.25 = 1.09317·S → S = 14.27 / 1.09317 = 13.06 in",
                  "reference": "ASHRAE Handbook—Fundamentals (2021), Ch. 21 Duct Design (Huebscher equivalent diameter)",
                  "step": "Square equivalent"
                },
                {
                  "calculation": "Re = D·V / ν = 1.1895 ft × 14.998 ft/s / 1.56×10⁻⁴ ft²/s = 114,361",
                  "reference": null,
                  "step": "Round duct: Reynolds number"
                }
              ],
              "unit_labels": {
                "airflow": "CFM",
                "area": "ft²",
                "condensate": "gal / h",
                "density": "lb / ft³",
                "elevation": "ft",
                "enthalpy": "BTU / lb dry air",
                "friction_rate": "in. w.g. / 100 ft",
                "grains": "gr / lb dry air",
                "humidity_ratio": "lb water / lb dry air",
                "length": "in",
                "load": "MBH (1,000 BTU/h)",
                "pressure": "psia",
                "relative_humidity": "%",
                "specific_volume": "ft³ / lb dry air",
                "temperature": "°F",
                "velocity": "FPM",
                "velocity_pressure": "in. w.g."
              },
              "units": "IP",
              "velocity": 900,
              "velocity_pressure": 0.0505
            },
            "type": "json"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
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                  "additionalProperties": false,
                  "properties": {
                    "airflow": {
                      "description": "Airflow: CFM (IP) or L/s (SI).",
                      "exclusiveMinimum": 0,
                      "type": "number"
                    },
                    "diameter": {
                      "description": "Round duct diameter: in (IP) or mm (SI).",
                      "exclusiveMinimum": 0,
                      "type": "number"
                    },
                    "friction_rate": {
                      "description": "Friction loss: in. w.g. per 100 ft (IP, typically 0.05-0.15) or Pa/m (SI, typically 0.4-1.2). With airflow, this is equal-friction sizing.",
                      "exclusiveMinimum": 0,
                      "type": "number"
                    },
                    "height": {
                      "description": "Rectangular height: in or mm.",
                      "exclusiveMinimum": 0,
                      "type": "number"
                    },
                    "units": {
                      "default": "IP",
                      "description": "\"IP\" (°F, CFM, in, BTU) or \"SI\" (°C, L/s, mm, kW). Default IP. Applies to inputs and results.",
                      "enum": [
                        "IP",
                        "SI"
                      ],
                      "type": "string"
                    },
                    "velocity": {
                      "description": "Air velocity: FPM (IP) or m/s (SI).",
                      "exclusiveMinimum": 0,
                      "type": "number"
                    },
                    "via": {
                      "description": "Optional: the tool whose next_calls suggested this call (filled in for you).",
                      "maxLength": 64,
                      "type": "string"
                    },
                    "width": {
                      "description": "Rectangular width: in or mm. With height, the duct size; alone, a fixed side (e.g. a ceiling depth) the other side is solved for.",
                      "exclusiveMinimum": 0,
                      "type": "number"
                    }
                  },
                  "type": "object"
                },
                "bodyType": {
                  "enum": [
                    "json",
                    "form-data",
                    "text"
                  ],
                  "type": "string"
                },
                "method": {
                  "enum": [
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                  ],
                  "type": "string"
                },
                "type": {
                  "const": "http",
                  "type": "string"
                }
              },
              "required": [
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                "method",
                "bodyType",
                "body"
              ],
              "type": "object"
            },
            "output": {
              "properties": {
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                },
                "type": {
                  "type": "string"
                }
              },
              "required": [
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              ],
              "type": "object"
            }
          },
          "required": [
            "input"
          ],
          "type": "object"
        }
      }
    },
    "lastUpdated": "2026-10-25T11:38:08.727Z",
    "quality": {
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      "l30DaysUniquePayers": 3,
      "lastCalledAt": "2026-10-25T11:38:08.5Z"
    },
    "resource": "https://x402-agent-api.onrender.com/api/v1/hvac-duct-size",
    "serviceName": "Agent Utility Suite",
    "tags": [
      "hvac",
      "duct-sizing",
      "engineering",
      "mechanical-engineering",
      "ashrae"
    ],
    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "HVAC duct sizing calculator: any two of duct size (round or rectangular), airflow, velocity and friction rate. Round and rectangular equivalents, nearest standard sizes, friction loss per 100 ft (Darcy-Weisbach, Colebrook), velocity pressure, design checks. Equal-friction sizing, fixed-depth ducts, IP or SI. Shows every step with the numbers. $0.002 USDC per call."
}

What the leaf hashes

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Proof

Its day has not closed yet. A day closes ten minutes after midnight UTC; the proof appears here then.