Get a served probabilistic forecast

Read /api/v1/grid/forecast-capabilities for published models, variables, markets, target kinds, horizons, quantiles and vintage modes. Select a source or model and variable; requests without selectors remain price reads. Metis 1 Preview currently serves price at settlement points: hubs (HB_), load zones (LZ_) and resource nodes use targetKind=node. Other registered variables use their published native targets and units. Omitting both dates on a latest read returns the requested horizon. Each point carries the point forecast and compatibility p10/p50/p90 fields, plus requested published levels in levels; source.quantiles names the returned set. Where available, bucketProbabilities and distributionSupports describe the full interval distribution. These are marginal distributions per interval, not joint scenarios. vintageMode=historical-comparison stitches no-hindsight vintages for evaluation, each settled target from the earliest run that covered it; vintageMode=latest-before stitches the newest run issued before each settled target, or at least leadHours before it. vintageMode=auction-matched returns, for each delivery interval whose day-ahead auction has closed, the newest run issued at or before that market's day-ahead deadline: the forecast a day-ahead bidder could have used. Historical windows are capped at 48 hours; auction-matched and latest-before with leadHours at 8 days. detail=levels omits bucket probabilities and supports.