D06-F02-A13 · LEVEL 2 GUIDED LAB · SYNTHETIC DATA

Belt Hold

Did price open at one extreme and travel directionally with almost no opening-side shadow? Walk the evidence clock one stage at a time. This lab teaches the publication contract; it does not simulate returns, platform parity, or trade performance.

Selected expression

bullish: open near low and close > open; bearish: open near high and close < open, with a long real body

Availability rule

The label becomes available only after the final candle in the selected pattern has closed; prior-trend context must use observations available before that close.

calculated · step 1 of 7

Verified synthetic fixture

This lab is paired with datasets/implementation-fixtures.json: 96 deterministic, oldest-to-newest observations spanning oscillating, rising, and moderating regimes. It is teaching data—not market history or predictive evidence.

Canonical latest output (D06-F02-A13)
{
  "label": "none",
  "score": 0.11921211954649767
}

Executable checks cover this result, flat/zero-volume boundaries, invalid timestamps, and prefix causality in both language entry points.