{"id":124838,"recorded_at":"2026-10-26T14:40:25.326128Z","observed_at":"2026-10-26T14:40:25.326052Z","subject_kind":"source_record","subject":"x402_bazaar:https://x402-agent-api.onrender.com/api/v1/hvac-duct-size","kind":"listing","method":"baseline/1","body":{"endpoints":[["x402","https://x402-agent-api.onrender.com/api/v1/hvac-duct-size"]],"name":"Agent Utility Suite","owner_address":"0x6847231bd28e16a0a57c59793f6b8bd8cc0043ac","raw":{"accepts":[{"amount":"2000","asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","extra":{"name":"USD Coin","version":"2"},"maxTimeoutSeconds":120,"network":"eip155:8453","payTo":"0x6847231bD28E16A0A57c59793f6B8BD8CC0043aC","scheme":"exact"}],"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). 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