diff --git a/model/api.go b/model/api.go
index 096196d..6ea493a 100644
--- a/model/api.go
+++ b/model/api.go
@@ -21,8 +21,8 @@ type MessageBuilder[T any] interface {
 	Assistant(prompt string) T
 }
 
-type Protocol[T any] interface {
+type Protocol interface {
 	Inputer
 	Outputer
-	MessageBuilder[T]
+	MessageBuilder[Protocol]
 }
diff --git a/model/ollama.go b/model/ollama.go
index 5cb9dd8..25fca44 100644
--- a/model/ollama.go
+++ b/model/ollama.go
@@ -8,8 +8,8 @@ import (
 
 // OLLaMA as an specified example.
 type OLLaMA struct {
-	sep               string
-	Protocol[*OLLaMA] `json:"-"`
+	sep      string
+	Protocol `json:"-"`
 	// callback only
 	ID       string    `json:"id,omitempty"`
 	Object   string    `json:"object,omitempty"`
diff --git a/model/openai.go b/model/openai.go
index d274e56..33e6dbe 100644
--- a/model/openai.go
+++ b/model/openai.go
@@ -23,8 +23,8 @@ type Choice struct {
 
 // OpenAI as an specified example.
 type OpenAI struct {
-	sep               string
-	Protocol[*OpenAI] `json:"-"`
+	sep      string
+	Protocol `json:"-"`
 	// callback only
 	ID      string   `json:"id,omitempty"`
 	Object  string   `json:"object,omitempty"`