Production bug 2026-05-02 22:19:
Intent 'post author username text (exclude bottom tabs)' contained the
word 'tab' in its parenthetical qualifier. The old check:
is_tab_intent = 'tab' in intent_lower
matched this intent as a TAB navigation intent, activating the Tab
Height Guard which excluded ALL nodes with center_y < 85% of screen.
This nuked the actual clips_author_username node at y=2012, leaving
only 4 irrelevant items for the VLM → bot stuck in a loop unable to
find the author username.
Fix: Replace substring match with precise regex patterns that only
match real tab navigation intents:
- 'tap profile tab', 'tap home tab' (tap + word + tab)
- 'profile tab', 'explore tab' (word + tab)
- 'tab ...' at start of intent
TDD: Red test added first, reproducing exact production state.
81 perception tests + 172 total tests pass.
Marc Mintel
cff7e976e0