Weak endings need a full vowel; trailing sibilant is transparent

middle / unavoidable shared only a schwa+L tail — the weak-ending rule
firing on a reduced vowel. Weak endings now require a full final vowel
(infancy/see on IY stays). Surfaced that swimmers' plural -s blocked
its coda from nesting with finisher; a trailing sibilant is inflection,
so it's stripped from the coda tag — Wayne's chain stays whole, garbage
(JH) still stays out.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app.py

@@ -344,6 +344,8 @@ def _final_coda_tag(pl: list[str]) -> str:
         if p[-1].isdigit():
             last = i
     coda = "".join(_coda_class(DIGITS.sub("", p)) for p in pl[last + 1:])
+    if coda.endswith("S"):
+        coda = coda[:-1]  # trailing plural/3rd-person sibilant is transparent
     return coda or "."
 
 
@@ -398,6 +400,10 @@ def weak_end_key(word: str) -> str | None:
     for i in range(len(pl) - 1, -1, -1):
         if pl[i][-1].isdigit():
             syl = [DIGITS.sub("", p) for p in pl[i:]]
+            if syl[0] in REDUCED:
+                return None  # a bare schwa tail (-le, -able) rhymes
+                # everything; weak endings need a full final vowel
+                # (infancy/see on IY, not middle/unavoidable on AH-L)
             out = [syl[0]] + [_coda_class(c) for c in syl[1:]]
             return "w:" + " ".join(out)
     return None

tests/test_rhymes.py

@@ -714,3 +714,12 @@ def test_garbage_javascript_dont_attach():
         bg[t["g"]].add(res["lines"][t["l"]][t["s"]:t["e"]].lower())
     dfam = next(s for s in bg.values() if "dollar" in s)
     assert "garbage" not in dfam and "javascript" not in dfam
+
+
+def test_weak_ending_needs_a_full_vowel():
+    # middle and unavoidable share only a schwa+L tail — too weak to rhyme
+    text = ("Wednesday has given up and admitted it's the middle\n"
+            "slightly apologetic and entirely unavoidable")
+    assert "middle" not in highlighted(text)
+    # but a full-vowel feminine ending still pairs (infancy/see on IY)
+    group_with("all I can see\nin my infancy", "see", "infancy")