Add support for displaying reasoning for openrouter models

src/api/providers/openrouter.ts

@@ -10,6 +10,7 @@ import delay from "delay"
 // Add custom interface for OpenRouter params
 type OpenRouterChatCompletionParams = OpenAI.Chat.ChatCompletionCreateParams & {
 	transforms?: string[]
+	include_reasoning?: boolean
 }
 
 // Add custom interface for OpenRouter usage chunk
@@ -126,6 +127,7 @@ export class OpenRouterHandler implements ApiHandler, SingleCompletionHandler {
 			temperature: temperature,
 			messages: openAiMessages,
 			stream: true,
+			include_reasoning: true,
 			// This way, the transforms field will only be included in the parameters when openRouterUseMiddleOutTransform is true.
 			...(this.options.openRouterUseMiddleOutTransform && { transforms: ["middle-out"] }),
 		} as OpenRouterChatCompletionParams)
@@ -145,6 +147,12 @@ export class OpenRouterHandler implements ApiHandler, SingleCompletionHandler {
 			}
 
 			const delta = chunk.choices[0]?.delta
+			if ("reasoning" in delta && delta.reasoning) {
+				yield {
+					type: "reasoning",
+					text: delta.reasoning,
+				} as ApiStreamChunk
+			}
 			if (delta?.content) {
 				fullResponseText += delta.content
 				yield {

src/api/transform/stream.ts

@@ -1,11 +1,16 @@
 export type ApiStream = AsyncGenerator<ApiStreamChunk>
-export type ApiStreamChunk = ApiStreamTextChunk | ApiStreamUsageChunk
+export type ApiStreamChunk = ApiStreamTextChunk | ApiStreamUsageChunk | ApiStreamReasoningChunk
 
 export interface ApiStreamTextChunk {
 	type: "text"
 	text: string
 }
 
+export interface ApiStreamReasoningChunk {
+	type: "reasoning"
+	text: string
+}
+
 export interface ApiStreamUsageChunk {
 	type: "usage"
 	inputTokens: number