Codex flagged the previous fix (1c08ac3f, "skip on unresolved ref")
as too conservative: a sub-agent's button with `\$color-accent` bg
and a text child WITHOUT a fill ended up with no fill at all when
doc.variables hadn't been seeded yet — text falls back to black,
which is invisible on a dark accent button.
Better fix: extend `resolveColorMaybeRef` with a step-2 fallback
into the built-in semantic palette (`getSemanticPaletteHex`). Every
core token (`color-accent`, `color-bg`, `color-text-primary`, etc.)
has a known hex for both `Light` and `Dark` modes, so the cascade
now is:
1. Doc-seeded variables (user's palette).
2. Built-in semantic palette for the requested mode.
3. Original ref string (unresolvable) — caller bails.
In the food-app + GPT-5.5 path, step 1 already worked because
`seedDocVariablesFromStyleGuide` runs before the sub-agents.
The fallback is for paths that bypass seeding (test fixtures,
external MCP callers, mid-flight states), not the common case.
Skip-on-NaN behavior stays — it now only triggers for genuinely
unknown tokens (`\$color-foobar` or similar), where any guess is
worse than leaving the model's existing fill alone.
Tests:
- New: `\$color-accent` ref resolves to #2563EB via semantic palette
even with no doc.variables, contrast pass picks white fg correctly
for the unfilled text child.
- New: `\$color-mystery-token` (not in palette) — step-2 misses,
contrast pass skips, existing text fill survives.
- Replaces the prior "skips on unresolved" test which over-asserted
the conservative path.
0bbdb0bf35