From fdc91274835668cd7566cd8318e60c9054bcd4a6 Mon Sep 17 00:00:00 2001
From: ctan <ctan@home.fr>
Date: Wed, 16 Sep 2026 19:58:30 +0200
Subject: [PATCH] fix(rules): Toughness is +3 hp below 4 Hit Dice (max(3,
 level))

---
 src/pf1e_simulator/abilities.py |  8 ++++----
 tests/test_feats.py             | 15 +++++++++++++++
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/src/pf1e_simulator/abilities.py b/src/pf1e_simulator/abilities.py
index 7cc7a2c..c120b1a 100644
--- a/src/pf1e_simulator/abilities.py
+++ b/src/pf1e_simulator/abilities.py
@@ -49,16 +49,16 @@ def weapon_focus(weapon_name: str) -> AbilitySpec:
     )
 
 
-# Toughness: +1 HP per Hit Die (approximated as +level HP, untyped, CRB)
-# For simplicity at this stage, we model it as a flat HP bonus.
-# The engine doesn't yet compute per-HD bonuses, so the caller sets the value.
+# Toughness (CRB): "+3 hit points. If the character has 4 or more Hit Dice,
+# she gains +1 hit point per Hit Die." => max(3, HD). The engine doesn't yet
+# compute per-HD bonuses, so the caller passes the level.
 def toughness(level: int) -> AbilitySpec:
     return AbilitySpec(
         name="Toughness",
         category="feat",
         source_detail="feat lv1",
         effects=(
-            StatModifier(target="hp", value=level),
+            StatModifier(target="hp", value=max(3, level)),
         ),
     )
 
diff --git a/tests/test_feats.py b/tests/test_feats.py
index 00baa28..95a4aee 100644
--- a/tests/test_feats.py
+++ b/tests/test_feats.py
@@ -135,6 +135,21 @@ def test_spot_check_toughness_level_tied() -> None:
     assert any(e.value == 5 for e in spec.effects)
 
 
+def test_toughness_is_plus3_below_four_hd_and_plus_hd_above() -> None:
+    # CRB Toughness: "+3 hit points. If the character has 4 or more Hit
+    # Dice, she gains +1 hit point per Hit Die."
+    def hp_value(level: int) -> int:
+        spec = _resolve_feat("Toughness", level)
+        values = [e.value for e in spec.effects if e.target == "hp"]
+        assert len(values) == 1
+        return values[0]
+
+    assert hp_value(1) == 3
+    assert hp_value(2) == 3
+    assert hp_value(3) == 3
+    assert hp_value(4) == 4
+
+
 # ── Expected mapping table (name -> resolved display name or traced-no-op) ─────
 
 _EXPECTED_RESOLUTION: dict[str, str] = {