diff --git a/run.go b/run.go
index 094b0a4..6bd3933 100644
--- a/run.go
+++ b/run.go
@@ -92,6 +92,7 @@ type RunRequest struct {
 	// Sampling temperature between 0 and 2. Higher values like 0.8 are  more random.
 	// lower values are more focused and deterministic.
 	Temperature *float32 `json:"temperature,omitempty"`
+	TopP        *float32 `json:"top_p,omitempty"`
 
 	// The maximum number of prompt tokens that may be used over the course of the run.
 	// If the run exceeds the number of prompt tokens specified, the run will end with status 'complete'.
@@ -103,6 +104,11 @@ type RunRequest struct {
 
 	// ThreadTruncationStrategy defines the truncation strategy to use for the thread.
 	TruncationStrategy *ThreadTruncationStrategy `json:"truncation_strategy,omitempty"`
+
+	// This can be either a string or a ToolChoice object.
+	ToolChoice any `json:"tool_choice,omitempty"`
+	// This can be either a string or a ResponseFormat object.
+	ResponseFormat any `json:"response_format,omitempty"`
 }
 
 // ThreadTruncationStrategy defines the truncation strategy to use for the thread.
@@ -124,6 +130,13 @@ const (
 	TruncationStrategyLastMessages = TruncationStrategy("last_messages")
 )
 
+// ReponseFormat specifies the format the model must output.
+// https://platform.openai.com/docs/api-reference/runs/createRun#runs-createrun-response_format.
+// Type can either be text or json_object.
+type ReponseFormat struct {
+	Type string `json:"type"`
+}
+
 type RunModifyRequest struct {
 	Metadata map[string]any `json:"metadata,omitempty"`
 }