Its case 2 expected a host token alone to draw Mapbox, the rule until 2026-09-28. It was in no
chain, so it never ran against the change that made that false, and nothing else measured the case
the change is about. The cases now:
1 no token: MapLibre, zero Mapbox requests, painted, no prompt (unchanged)
2 a host token alone: still MapLibre, painted, zero Mapbox requests
3 ?provider=mapbox with that token: Mapbox, carrying that token
It joins gates:post beside check:leaf-engine-per-provider, together with check:engine-contract
(gospel's resources-map uses the engine it was asked for, or fails visibly), which was also in no
chain. Both are browser gates: NOT MEASURED outside the browser slot, measured in it.
Only the browser seat runs browsers, and only inside internal/browser-slot.sh.
That rule was remembered, not enforced: an agent ran a gate it took for a
headless source check and it launched Chromium outside the slot.
internal/lib/playwright-guarded.mjs is now the one way a repo file reaches
playwright: its launch(), launchPersistentContext(), launchServer(), connect()
and connectOverCDP() exit 75 (NOT MEASURED) with a message naming
browser-slot.sh unless DOXA_BROWSER_SLOT is set, and browser-slot.sh exports it
for the command it runs, so a bash -c grandchild inherits it. All 72 files that
imported playwright switch to it (internal/lib/browser.mjs and 64 internal gates;
plugin-designs scripts: doxa-research-map 3, my-upg-100-list 2,
research-map-plus-grid 2, research-dashboard 1): a mechanical import swap.
check:browser-gates-guarded (gates:pre) fails a direct import;
bun run browser-gates lists the 97 scripts that launch a browser. isBrowserGate
moves to internal/lib/browser-gates.mjs so the runner and the check share it.
