{"doctrine":"Every endpoint we sell grades itself against reality in public. This is /weather/consensus's ledger: each UTC day we record the EXACT paid handler's day-max forecast for 6 fixed cities, then grade it 2+ days later against the ERA5 reanalysis archive (an independent pipeline). Hits, misses, bias — shown, not claimed.","endpoint":"GET /weather/consensus","predictions_recorded":36,"graded":24,"pending":12,"mae_c":1.67,"bias_c":-0.9,"by_city":{"nyc":{"n":4,"mae_c":1.6},"la":{"n":4,"mae_c":2.38},"chicago":{"n":4,"mae_c":2.13},"miami":{"n":4,"mae_c":0.78},"london":{"n":4,"mae_c":0.22},"tokyo":{"n":4,"mae_c":2.9}},"recent":[{"city":"tokyo","date":"2026-07-27","predicted_max_c":29.4,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"london","date":"2026-07-27","predicted_max_c":24.8,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"miami","date":"2026-07-27","predicted_max_c":32.1,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"chicago","date":"2026-07-27","predicted_max_c":30.7,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"la","date":"2026-07-27","predicted_max_c":31.9,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"nyc","date":"2026-07-27","predicted_max_c":29.8,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"tokyo","date":"2026-07-26","predicted_max_c":31.5,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"london","date":"2026-07-26","predicted_max_c":24.5,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"miami","date":"2026-07-26","predicted_max_c":31.5,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"chicago","date":"2026-07-26","predicted_max_c":26.5,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"la","date":"2026-07-26","predicted_max_c":33,"actual_max_c":null,"abs_err_c":null,"graded":false},{"city":"nyc","date":"2026-07-26","predicted_max_c":27.8,"actual_max_c":null,"abs_err_c":null,"graded":false}],"method":{"predict":"vendored paid handler, Open-Meteo forecast leg, day-max, 1/city/day (6 cities, fixed forever)","grade":"ERA5 archive day-max, 2-day lag","durability":"append-only JSONL, git-snapshotted (tamper-evident), survives redeploys"},"as_of":"2026-07-27T22:06:25.889Z"}