Intervals
Vote share and seat estimates need P10/P50/P90 or an equivalent interval format, not just a single headline number.
Forecasts
No naked probabilities.
Forecasts will only publish with model version, input snapshot, uncertainty, source notes, and a backtest record that survives later model changes.
Versioning
Every forecast output is tied to a model id, code revision, source snapshot, and publication timestamp.
Backtests
Past predictions are immutable records used to report calibration, mean absolute error, and missed calls.