# Known Drift — markidocx-docs Corpus

Last updated: 2026-03-16

## Summary

The markidocx-docs corpus (PRD + FRS v0.2 + UCC) produces known structural drift
on round-trip at LEVEL1. This drift is expected and does not indicate a regression.

## Import mode: fallback (merged)

The three source files are composed into a single DOCX. On import the system attempts
to redistribute content back to the three origin files using source-boundary markers.
The current build pipeline embeds section markers but the 27 H1-level sections in the
combined document make boundary matching ambiguous, so the importer falls back to a
single merged output (`dist/imported_merged.md`).

**Classification:** expected / by-design. The merged output is complete and usable.

## Structural drift items

### Bold inline text in list items (broken: ~70 items)

List items containing `**bold**` inline spans lose the bold markers on round-trip.
python-docx represents inline bold as a `Run` with `bold=True`, but the importer's
list-item text extractor concatenates run text without restoring markdown bold syntax.

**Classification:** known limitation of LEVEL1 inline formatting in list items.
**FR reference:** FR-508 (unsupported construct visibility) — these are surfaced
explicitly as `broken` rather than silently accepted.
**Impact:** content is preserved, presentation marker is lost.

### Table (broken: 1 of 1)

One table in the UCC is detected as missing after round-trip. Likely cause: the table
contains merged cells or a header row structure that the importer does not reconstruct.

**Classification:** known LEVEL1 table limitation.
**Impact:** table content is present in the DOCX but not re-imported to Markdown.

## Verdict

902 elements preserved; ~71 broken items (all inline formatting in lists or 1 table).
This corpus is suitable as a regression baseline: a clean round-trip regression test
can assert `preserved >= 900` and `broken <= 80` rather than exact zero-drift.