Objective strands and every achievement-level descriptor come from
official/design_myp_criterion.pdf — the assessed
curriculum chapter of the MYP design guide, pages 31–45, covering years
1, 3 and 5. Every line on this page was re-checked against the text layer of
that PDF by build/extract.py --verify: 12 criteria, 60
achievement bands and 171 descriptor strands match verbatim. No corrections
were needed.
The band 1–2 descriptor states fewer strands than the objective lists
— two or three rather than four — because the IB collapses and
renumbers the strands at that level. That is the published rubric, not missing
data, and the page says so rather than aligning strands that do not
correspond.