Add support for Claude Haiku 4.5

Adds Claude Haiku 4.5 model with pricing of $1.00 per million input tokens
and $5.00 per million output tokens, following the October 15, 2025 release.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: mattgodbolt

app/model_costs.py

@@ -19,13 +19,14 @@ class ModelCost(NamedTuple):
 
 
 # Model family costs in USD per million tokens
-# Updated: 2025-09-16 based on https://claude.com/pricing
+# Updated: 2025-10-15 based on https://claude.com/pricing
 MODEL_FAMILIES = {
     "opus-4.1": ModelCost(15.0, 75.0),
     "opus-4": ModelCost(15.0, 75.0),
     "sonnet-4": ModelCost(3.0, 15.0),
     "sonnet-3.7": ModelCost(3.0, 15.0),
     "sonnet-3.5": ModelCost(3.0, 15.0),
+    "haiku-4.5": ModelCost(1.0, 5.0),
     "haiku-3.5": ModelCost(0.80, 4.0),
     "opus-3": ModelCost(15.0, 75.0),
     "haiku-3": ModelCost(0.25, 1.25),

app/test_model_costs.py

@@ -23,6 +23,7 @@ def test_claude_family_version_pattern(self):
         assert normalize_model_name("claude-sonnet-4-0") == "sonnet-4"
         assert normalize_model_name("claude-opus-4-0") == "opus-4"
         assert normalize_model_name("claude-sonnet-3-7") == "sonnet-3.7"
+        assert normalize_model_name("claude-haiku-4-5") == "haiku-4.5"
 
     def test_claude_family_major_pattern(self):
         """Test claude-family-X pattern."""
@@ -58,6 +59,12 @@ def test_fallback_pattern_specificity(self):
 class TestGetModelCost:
     """Test model cost lookup."""
 
+    def test_haiku_4_5_cost(self):
+        """Test Claude 4.5 Haiku costs."""
+        input_cost, output_cost = get_model_cost("claude-haiku-4-5")
+        assert input_cost == 1.0 / 1_000_000  # $1.00 per million
+        assert output_cost == 5.0 / 1_000_000  # $5.00 per million
+
     def test_haiku_3_5_cost(self):
         """Test Claude 3.5 Haiku costs."""
         input_cost, output_cost = get_model_cost("claude-3-5-haiku-20241022")