diff --git a/.stats.yml b/.stats.yml
index 4e4cb55..6cc7757 100644
--- a/.stats.yml
+++ b/.stats.yml
@@ -1,2 +1,2 @@
 configured_endpoints: 68
-openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/openai-77cfff37114bc9f141c7e6107eb5f1b38d8cc99bc3d4ce03a066db2b6b649c69.yml
+openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/openai-b04761ffd2adad3cc19a6dc6fc696ac445878219972f891881a967340fa9a6b0.yml
diff --git a/audio.go b/audio.go
index 3828a8b..1d40eff 100644
--- a/audio.go
+++ b/audio.go
@@ -31,16 +31,8 @@ func NewAudioService(opts ...option.RequestOption) (r *AudioService) {
 	return
 }
 
-type AudioModel string
+type AudioModel = string
 
 const (
 	AudioModelWhisper1 AudioModel = "whisper-1"
 )
-
-func (r AudioModel) IsKnown() bool {
-	switch r {
-	case AudioModelWhisper1:
-		return true
-	}
-	return false
-}
diff --git a/audiospeech.go b/audiospeech.go
index 2f97f16..780d957 100644
--- a/audiospeech.go
+++ b/audiospeech.go
@@ -40,21 +40,13 @@ func (r *AudioSpeechService) New(ctx context.Context, body AudioSpeechNewParams,
 	return
 }
 
-type SpeechModel string
+type SpeechModel = string
 
 const (
 	SpeechModelTTS1   SpeechModel = "tts-1"
 	SpeechModelTTS1HD SpeechModel = "tts-1-hd"
 )
 
-func (r SpeechModel) IsKnown() bool {
-	switch r {
-	case SpeechModelTTS1, SpeechModelTTS1HD:
-		return true
-	}
-	return false
-}
-
 type AudioSpeechNewParams struct {
 	// The text to generate audio for. The maximum length is 4096 characters.
 	Input param.Field[string] `json:"input,required"`
diff --git a/chat.go b/chat.go
index 999df42..404be7a 100644
--- a/chat.go
+++ b/chat.go
@@ -27,7 +27,7 @@ func NewChatService(opts ...option.RequestOption) (r *ChatService) {
 	return
 }
 
-type ChatModel string
+type ChatModel = string
 
 const (
 	ChatModelGPT4o               ChatModel = "gpt-4o"
@@ -54,11 +54,3 @@ const (
 	ChatModelGPT3_5Turbo0125     ChatModel = "gpt-3.5-turbo-0125"
 	ChatModelGPT3_5Turbo16k0613  ChatModel = "gpt-3.5-turbo-16k-0613"
 )
-
-func (r ChatModel) IsKnown() bool {
-	switch r {
-	case ChatModelGPT4o, ChatModelGPT4o2024_05_13, ChatModelGPT4oMini, ChatModelGPT4oMini2024_07_18, ChatModelGPT4Turbo, ChatModelGPT4Turbo2024_04_09, ChatModelGPT4_0125Preview, ChatModelGPT4TurboPreview, ChatModelGPT4_1106Preview, ChatModelGPT4VisionPreview, ChatModelGPT4, ChatModelGPT4_0314, ChatModelGPT4_0613, ChatModelGPT4_32k, ChatModelGPT4_32k0314, ChatModelGPT4_32k0613, ChatModelGPT3_5Turbo, ChatModelGPT3_5Turbo16k, ChatModelGPT3_5Turbo0301, ChatModelGPT3_5Turbo0613, ChatModelGPT3_5Turbo1106, ChatModelGPT3_5Turbo0125, ChatModelGPT3_5Turbo16k0613:
-		return true
-	}
-	return false
-}
diff --git a/image.go b/image.go
index 73b0c3f..7a17c05 100644
--- a/image.go
+++ b/image.go
@@ -89,21 +89,13 @@ func (r imageJSON) RawJSON() string {
 	return r.raw
 }
 
-type ImageModel string
+type ImageModel = string
 
 const (
 	ImageModelDallE2 ImageModel = "dall-e-2"
 	ImageModelDallE3 ImageModel = "dall-e-3"
 )
 
-func (r ImageModel) IsKnown() bool {
-	switch r {
-	case ImageModelDallE2, ImageModelDallE3:
-		return true
-	}
-	return false
-}
-
 type ImagesResponse struct {
 	Created int64              `json:"created,required"`
 	Data    []Image            `json:"data,required"`
diff --git a/moderation.go b/moderation.go
index d42ad21..7cf711d 100644
--- a/moderation.go
+++ b/moderation.go
@@ -185,21 +185,13 @@ func (r moderationCategoryScoresJSON) RawJSON() string {
 	return r.raw
 }
 
-type ModerationModel string
+type ModerationModel = string
 
 const (
 	ModerationModelTextModerationLatest ModerationModel = "text-moderation-latest"
 	ModerationModelTextModerationStable ModerationModel = "text-moderation-stable"
 )
 
-func (r ModerationModel) IsKnown() bool {
-	switch r {
-	case ModerationModelTextModerationLatest, ModerationModelTextModerationStable:
-		return true
-	}
-	return false
-}
-
 // Represents if a given text input is potentially harmful.
 type ModerationNewResponse struct {
 	// The unique identifier for the moderation request.