fix

apps/api/internal/processing/formula_prompt_test.go

@@ -38,6 +38,9 @@ func TestFormatDescriptionFormulaConstraint(t *testing.T) {
 			map[string]any{"type": "ul", "instructions": "3 bullets of specs"},
 		},
 	})
+	if !strings.Contains(got, "REQUIRED") || !strings.Contains(got, "<hN>") {
+		t.Fatalf("missing required HTML guidance: %s", got)
+	}
 	if !strings.Contains(got, "- h1: Main product heading") {
 		t.Fatalf("missing h1: %s", got)
 	}
@@ -49,6 +52,30 @@ func TestFormatDescriptionFormulaConstraint(t *testing.T) {
 	}
 }
 
+func TestAppendDescriptionFormulaSystemOverride(t *testing.T) {
+	t.Parallel()
+	desc := map[string]any{
+		"sections": []any{
+			map[string]any{"type": "h1", "instructions": "Heading"},
+			map[string]any{"type": "p", "instructions": "Body"},
+		},
+	}
+	sys, user := resolveProductPromptTemplates(ProductInput{
+		EnhanceSystemTemplate: "Retail product copywriter.\n- description: 1-2 factual sentences",
+		EnhanceUserTemplate:   "Name: {{name}}",
+		DescriptionTemplate:   desc,
+	})
+	if !strings.Contains(user, "Description formula") {
+		t.Fatalf("missing user formula: %s", user)
+	}
+	if !strings.Contains(sys, "Description formula") || !strings.Contains(sys, "1-2 sentences") {
+		t.Fatalf("system should keep company text and append formula override: %s", sys)
+	}
+	if AppendDescriptionFormulaSystemOverride("plain", nil) != "plain" {
+		t.Fatal("empty formula must be no-op")
+	}
+}
+
 func TestAppendFormulaConstraints_injectedIntoResolve(t *testing.T) {
 	t.Parallel()
 	title := map[string]any{