Fix generator quality issues and run initial corpus pipeline

Pre-corpus fixes (from EVALUATION.md):
- Clean 2,264 contaminated rows from augmented relations (bridge
  artifacts, full-sentence HasProperty values, null bytes, empty words)
- Fix article logic: dynamic a/an across Deconstruction, FalseEquivalence,
  DenialOfConsequences, TautologicalWisdom templates
- Tighten _short_concepts() default from max_words=3 to 2
- Fix FutilePreparation gerunding: filter vocab nouns and noun-suffix
  words from UsedFor targets; fix CVC doubling for 'y'-ending words
- Add _looks_like_verb() heuristic, improve _a() for vowel-sound edges

Pipeline hardening:
- polish_corpus.py: context-size fallback (truncate chain, then minimal
  prompt), classified error types, consecutive-error circuit breaker,
  10-entry flush granularity, ETA tracking, KeyboardInterrupt handling
- generate_raw_batch.sh: fix python -> python3

Corpus generation run (9,835 raw -> 5,499 polished -> 2,312 filtered):
- 44.1% discard rate, 0 errors, 82 minutes on RTX 4090
- 9,257 training pairs across 5 input framing types
- 97.6% vocab coverage (609/624 words)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

folksy_generator.py

@@ -199,10 +199,10 @@ class Deconstruction(MetaTemplate):
     id = "deconstruction"
     name = "Deconstruction"
     surface_templates = [
-        "You know what they say, a {A} with no {B} is just a {C} {D}.",
+        "You know what they say, {A_article} with no {B} is just a {C} {D}.",
         "Take the {B} out of {A} and all you've got left is {C} {D}.",
         "{A} without {B}? That's just {D} with ideas above its station.",
-        "An {A} ain't nothing but {D} that met some {B}.",
+        "{A_Article} ain't nothing but {D} that met some {B}.",
     ]
 
     def generate(self, seed_word=None, seed_category=None):
@@ -255,7 +255,8 @@ class Deconstruction(MetaTemplate):
             c_word = random.choice(["plain", "sorry", "old", "humble", "dry", "wet", "cold"])
 
         template = self._pick_template()
-        saying = template.format(A=a, B=b_word, C=c_word, D=d_word)
+        saying = template.format(A=a, A_article=_a(a), A_Article=_a(a).capitalize(),
+                                  B=b_word, C=c_word, D=d_word)
 
         debug = {
             "template_family": self.id,
@@ -275,8 +276,8 @@ class DenialOfConsequences(MetaTemplate):
     surface_templates = [
         "Don't {C} the {A} and say you ain't got {B}.",
         "Don't {C} the {A} and act surprised when the {B} show up.",
-        "Man who {C}s a {A} can't complain about {B}.",
-        "You can't {C} a {A} and then wonder where all the {B} came from.",
+        "Man who {C}s {A_article} can't complain about {B}.",
+        "You can't {C} {A_article} and then wonder where all the {B} came from.",
     ]
 
     def generate(self, seed_word=None, seed_category=None):
@@ -323,7 +324,7 @@ class DenialOfConsequences(MetaTemplate):
             c_word = random.choice(["build", "set up", "put out", "lay down", "make"])
 
         template = self._pick_template()
-        saying = template.format(A=a, B=b_word, C=c_word)
+        saying = template.format(A=a, A_article=_a(a), B=b_word, C=c_word)
 
         debug = {
             "template_family": self.id,
@@ -407,8 +408,9 @@ class FutilePreparation(MetaTemplate):
         if not seed:
             return None, None
 
-        # What is the seed used for?
+        # What is the seed used for? Filter out vocab nouns and noun-like words — we need verbs.
         uses = _short_concepts(self.graph.neighbors(seed, "UsedFor", min_weight=0.5), max_words=2)
+        uses = [u for u in uses if u[0] not in self.graph.vocab and _looks_like_verb(u[0])]
         if not uses:
             return None, None
 
@@ -532,9 +534,9 @@ class TautologicalWisdom(MetaTemplate):
     id = "tautological_wisdom"
     name = "Tautological Wisdom"
     surface_templates = [
-        "You know what they say, it takes a {X} to get a {Y}.",
+        "You know what they say, it takes {X_article} to get {Y_article}.",
         "My daddy always said, can't have {Y} without {X}.",
-        "A {Y} don't come without its {X}, now does it?",
+        "{Y_Article} don't come without its {X}, now does it?",
         "You want {Y}? Well, first you're gonna need {X}.",
         "Ain't no {Y} ever came from nothing — you need {X}.",
     ]
@@ -566,7 +568,9 @@ class TautologicalWisdom(MetaTemplate):
         chain_edge = choice[3]
 
         template = self._pick_template()
-        saying = template.format(X=x_word, Y=y_word)
+        saying = template.format(X=x_word, Y=y_word,
+                                  X_article=_a(x_word), Y_article=_a(y_word),
+                                  Y_Article=_a(y_word).capitalize())
 
         debug = {
             "template_family": self.id,
@@ -584,10 +588,10 @@ class FalseEquivalence(MetaTemplate):
     id = "false_equivalence"
     name = "False Equivalence"
     surface_templates = [
-        "A {A} is just a {B} that's got {P}.",
-        "What's a {A} but a {B} with {P}?",
-        "The only difference between a {A} and a {B} is {P}.",
-        "Take the {P} from a {A} and you've got yourself a {B}.",
+        "{A_article} is just {B_article} that's got {P}.",
+        "What's {A_article} but {B_article} with {P}?",
+        "The only difference between {A_article} and {B_article} is {P}.",
+        "Take the {P} from {A_article} and you've got yourself {B_article}.",
     ]
 
     def generate(self, seed_word=None, seed_category=None):
@@ -635,7 +639,8 @@ class FalseEquivalence(MetaTemplate):
                 p_word = random.choice(["ambition", "an attitude", "a plan", "patience"])
 
         template = self._pick_template()
-        saying = template.format(A=a, B=b_word, P=p_word)
+        saying = template.format(A=a, B=b_word, P=p_word,
+                                 A_article=_a(a), B_article=_a(b_word))
 
         debug = {
             "template_family": self.id,
@@ -656,7 +661,7 @@ def _readable(concept):
     return concept.replace("_", " ")
 
 
-def _short_concepts(items, max_words=3):
+def _short_concepts(items, max_words=2):
     """Filter concept tuples to only those with short readable names.
 
     Items can be tuples where first element is the concept string.
@@ -672,14 +677,37 @@ def _gerund(word):
         return word[:-1] + "ing"
     if word.endswith("ing"):
         return word
-    if len(word) > 2 and word[-1] not in "aeiou" and word[-2] in "aeiou" and word[-3] not in "aeiou":
+    # CVC doubling: "run" -> "running", "sit" -> "sitting"
+    # Treat 'y' and 'w' as vowels at word end (prey->preying, not preyying)
+    if len(word) > 2 and word[-1] not in "aeiouy" and word[-2] in "aeiou" and word[-3] not in "aeiou":
         return word + word[-1] + "ing"
     return word + "ing"
 
 
+def _looks_like_verb(word):
+    """Heuristic: does this word look like it could be a verb?
+    Rejects words with obvious noun/adjective suffixes."""
+    w = word.split("_")[0].lower() if "_" in word else word.lower()
+    noun_suffixes = ("tion", "sion", "ment", "ness", "ity", "ance", "ence",
+                     "ture", "ism", "ist", "ery", "ory", "ling")
+    return not any(w.endswith(s) for s in noun_suffixes)
+
+
 def _a(word):
     """Add 'a' or 'an' article."""
-    if word and word[0] in "aeiou":
+    if not word:
+        return "a"
+    first = word.split()[0].lower() if word else ""
+    # Words that start with a vowel letter but consonant sound
+    consonant_sound = ("uni", "use", "used", "user", "usual", "usu", "uti", "uto",
+                       "uro", "uku", "ula")
+    # Words that start with a consonant letter but vowel sound
+    vowel_sound = ("hour", "honest", "honor", "honour", "heir", "herb")
+    if any(first.startswith(p) for p in vowel_sound):
+        return f"an {word}"
+    if any(first.startswith(p) for p in consonant_sound):
+        return f"a {word}"
+    if first[0] in "aeiou":
         return f"an {word}"
     return f"a {word}"