diff --git a/API_VERSION b/API_VERSION
index fb72506858..50a784c118 100644
--- a/API_VERSION
+++ b/API_VERSION
@@ -1 +1 @@
-2025-09-30.clover
\ No newline at end of file
+13e48677b8744cdd8170f92a48ed598952515497
\ No newline at end of file
diff --git a/OPENAPI_VERSION b/OPENAPI_VERSION
index f0bb0d526f..b3493174a2 100644
--- a/OPENAPI_VERSION
+++ b/OPENAPI_VERSION
@@ -1 +1 @@
-v2028
\ No newline at end of file
+v2042
\ No newline at end of file
diff --git a/billing_metereventsummary.go b/billing_metereventsummary.go
index c66ca6f069..5d3faaf6d3 100644
--- a/billing_metereventsummary.go
+++ b/billing_metereventsummary.go
@@ -9,7 +9,8 @@ package stripe
 // Retrieve a list of billing meter event summaries.
 type BillingMeterEventSummaryListParams struct {
 	ListParams `form:"*"`
-	ID         *string `form:"-"` // Included in URL
+	// Unique identifier for the object.
+	ID *string `form:"-"` // Included in URL
 	// The customer for which to fetch event summaries.
 	Customer *string `form:"customer"`
 	// The timestamp from when to stop aggregating meter events (exclusive). Must be aligned with minute boundaries.
diff --git a/error.go b/error.go
index 41dcc5b3cc..59a0b982e8 100644
--- a/error.go
+++ b/error.go
@@ -416,8 +416,8 @@ func (e *IdempotencyError) Error() string {
 
 // errorStructs: The beginning of the section generated from our OpenAPI spec
 
-// TemporarySessionExpiredError is the Go struct corresponding to the error type "temporary_session_expired."
-// Information about the error that occurred
+// TemporarySessionExpiredError is the Go struct corresponding to the error type "temporary_session_expired".
+// The temporary session token has expired.
 type TemporarySessionExpiredError struct {
 	APIResource
 	Code        string    `json:"code"`
diff --git a/example/generated_examples_test.go b/example/generated_examples_test.go
index d6e1271837..b6db5835c7 100644
--- a/example/generated_examples_test.go
+++ b/example/generated_examples_test.go
@@ -6479,6 +6479,44 @@ func TestPromotionCodesGet2Client(t *testing.T) {
 }
 
 func TestPromotionCodesPost(t *testing.T) {
+	params := &stripe.PromotionCodeParams{
+		Promotion: &stripe.PromotionCodePromotionParams{
+			Type:   stripe.String("coupon"),
+			Coupon: stripe.String("Z4OV52SU"),
+		},
+	}
+	result, err := promotioncode.New(params)
+	assert.NotNil(t, result)
+	assert.Nil(t, err)
+}
+
+func TestPromotionCodesPostService(t *testing.T) {
+	sc := client.New(TestAPIKey, nil)
+	params := &stripe.PromotionCodeParams{
+		Promotion: &stripe.PromotionCodePromotionParams{
+			Type:   stripe.String("coupon"),
+			Coupon: stripe.String("Z4OV52SU"),
+		},
+	}
+	result, err := sc.PromotionCodes.New(params)
+	assert.NotNil(t, result)
+	assert.Nil(t, err)
+}
+
+func TestPromotionCodesPostClient(t *testing.T) {
+	sc := stripe.NewClient(TestAPIKey)
+	params := &stripe.PromotionCodeCreateParams{
+		Promotion: &stripe.PromotionCodeCreatePromotionParams{
+			Type:   stripe.String("coupon"),
+			Coupon: stripe.String("Z4OV52SU"),
+		},
+	}
+	result, err := sc.V1PromotionCodes.Create(context.TODO(), params)
+	assert.NotNil(t, result)
+	assert.Nil(t, err)
+}
+
+func TestPromotionCodesPost2(t *testing.T) {
 	params := &stripe.PromotionCodeParams{}
 	params.AddMetadata("order_id", "6735")
 	result, err := promotioncode.Update("promo_xxxxxxxxxxxxx", params)
@@ -6486,7 +6524,7 @@ func TestPromotionCodesPost(t *testing.T) {
 	assert.Nil(t, err)
 }
 
-func TestPromotionCodesPostService(t *testing.T) {
+func TestPromotionCodesPost2Service(t *testing.T) {
 	sc := client.New(TestAPIKey, nil)
 	params := &stripe.PromotionCodeParams{}
 	params.AddMetadata("order_id", "6735")
@@ -6495,7 +6533,7 @@ func TestPromotionCodesPostService(t *testing.T) {
 	assert.Nil(t, err)
 }
 
-func TestPromotionCodesPostClient(t *testing.T) {
+func TestPromotionCodesPost2Client(t *testing.T) {
 	sc := stripe.NewClient(TestAPIKey)
 	params := &stripe.PromotionCodeUpdateParams{}
 	params.AddMetadata("order_id", "6735")
diff --git a/invoicelineitem.go b/invoicelineitem.go
index cb95f02398..b33b57d9e4 100644
--- a/invoicelineitem.go
+++ b/invoicelineitem.go
@@ -180,7 +180,8 @@ type InvoiceLineItemTaxAmountParams struct {
 // item and the invoice line item, so updates on this endpoint will propagate to the invoice item as well.
 // Updating an invoice's line item is only possible before the invoice is finalized.
 type InvoiceLineItemParams struct {
-	Params  `form:"*"`
+	Params `form:"*"`
+	// Invoice ID of line item
 	Invoice *string `form:"-"` // Included in URL
 	// The integer amount in cents (or local equivalent) of the charge to be applied to the upcoming invoice. If you want to apply a credit to the customer's account, pass a negative amount.
 	Amount *int64 `form:"amount"`
@@ -330,7 +331,8 @@ type InvoiceLineItemUpdateTaxAmountParams struct {
 // item and the invoice line item, so updates on this endpoint will propagate to the invoice item as well.
 // Updating an invoice's line item is only possible before the invoice is finalized.
 type InvoiceLineItemUpdateParams struct {
-	Params  `form:"*"`
+	Params `form:"*"`
+	// Invoice ID of line item
 	Invoice *string `form:"-"` // Included in URL
 	// The integer amount in cents (or local equivalent) of the charge to be applied to the upcoming invoice. If you want to apply a credit to the customer's account, pass a negative amount.
 	Amount *int64 `form:"amount"`
diff --git a/productfeature.go b/productfeature.go
index f0fe00528a..2eef6aca57 100644
--- a/productfeature.go
+++ b/productfeature.go
@@ -8,7 +8,8 @@ package stripe
 
 // Deletes the feature attachment to a product
 type ProductFeatureParams struct {
-	Params  `form:"*"`
+	Params `form:"*"`
+	// The ID of the product.
 	Product *string `form:"-"` // Included in URL
 	// The ID of the [Feature](https://stripe.com/docs/api/entitlements/feature) object attached to this product.
 	EntitlementFeature *string `form:"entitlement_feature"`
@@ -42,7 +43,8 @@ type ProductFeatureDeleteParams struct {
 
 // Retrieves a product_feature, which represents a feature attachment to a product
 type ProductFeatureRetrieveParams struct {
-	Params  `form:"*"`
+	Params `form:"*"`
+	// The ID of the product.
 	Product *string `form:"-"` // Included in URL
 	// Specifies which fields in the response should be expanded.
 	Expand []*string `form:"expand"`