fix: emit response.output_text.done and response.function_call_arguments.done in stream translator; align non-streaming output structure with streaming path

- stream-translator: emit content-level done events before output_item.done for each block
- response-translator: one OutputMessageItem per text block (shared outputIdx counter) to match streaming path structure

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: tombii

packages/openai-responses-adapter/src/__tests__/response-translator.test.ts

@@ -33,7 +33,7 @@ describe("translateAnthropicResponseToResponses", () => {
 		const item = result.output[0];
 		expect(item.type).toBe("message");
 		if (item.type === "message") {
-			expect(item.id).toBe("resp_001_msg");
+			expect(item.id).toBe("resp_001_msg_0");
 			expect(item.role).toBe("assistant");
 			expect(item.status).toBe("completed");
 			expect(item.content).toHaveLength(1);
@@ -186,7 +186,7 @@ describe("translateAnthropicResponseToResponses", () => {
 		expect(result.created_at).toBeGreaterThan(0);
 	});
 
-	test("multiple text blocks → concatenated into single output_text", () => {
+	test("multiple text blocks → one OutputMessageItem per block", () => {
 		const resp = makeBaseResponse({
 			content: [
 				{ type: "text", text: "Hello " },
@@ -199,12 +199,22 @@ describe("translateAnthropicResponseToResponses", () => {
 			"claude-3-5-sonnet-20241022",
 		);
 
-		expect(result.output).toHaveLength(1);
-		const item = result.output[0];
-		if (item.type === "message") {
+		expect(result.output).toHaveLength(2);
+		const item0 = result.output[0];
+		const item1 = result.output[1];
+		expect(item0.type).toBe("message");
+		expect(item1.type).toBe("message");
+		if (item0.type === "message") {
+			expect(item0.id).toBe("resp_007_msg_0");
+			expect(
+				item0.content[0].type === "output_text" && item0.content[0].text,
+			).toBe("Hello ");
+		}
+		if (item1.type === "message") {
+			expect(item1.id).toBe("resp_007_msg_1");
 			expect(
-				item.content[0].type === "output_text" && item.content[0].text,
-			).toBe("Hello world");
+				item1.content[0].type === "output_text" && item1.content[0].text,
+			).toBe("world");
 		}
 	});
 });

packages/openai-responses-adapter/src/__tests__/stream-translator.test.ts

@@ -106,9 +106,18 @@ describe("translateAnthropicStreamToResponses", () => {
 		const delta2 = parsed[3].data as Record<string, unknown>;
 		expect((delta2.delta as Record<string, unknown>).text).toBe(" world");
 
-		// Fifth: response.output_item.done with full text
-		expect(parsed[4].event).toBe("response.output_item.done");
-		const done = parsed[4].data as Record<string, unknown>;
+		// Fifth: response.output_text.done with full accumulated text
+		expect(parsed[4].event).toBe("response.output_text.done");
+		const textDone = parsed[4].data as Record<string, unknown>;
+		expect(textDone.type).toBe("response.output_text.done");
+		expect(textDone.item_id).toBe("resp_001_msg_0");
+		expect(textDone.output_index).toBe(0);
+		expect(textDone.content_index).toBe(0);
+		expect(textDone.text).toBe("Hello world");
+
+		// Sixth: response.output_item.done with full text
+		expect(parsed[5].event).toBe("response.output_item.done");
+		const done = parsed[5].data as Record<string, unknown>;
 		const doneItem = done.item as Record<string, unknown>;
 		expect(doneItem.type).toBe("message");
 		expect(doneItem.status).toBe("completed");

packages/openai-responses-adapter/src/response-translator.ts

@@ -10,39 +10,32 @@ export function translateAnthropicResponseToResponses(
 	responseId: string,
 	model: string,
 ): ResponsesResponse {
-	const textBlocks = resp.content.filter((c) => c.type === "text");
-	const toolBlocks = resp.content.filter((c) => c.type === "tool_use");
-
 	const output: ResponsesResponse["output"] = [];
 
-	if (textBlocks.length > 0) {
-		const combinedText = textBlocks
-			.map((c) => (c.type === "text" ? c.text : ""))
-			.join("");
-
-		const msgItem: OutputMessageItem = {
-			type: "message",
-			id: `${responseId}_msg`,
-			role: "assistant",
-			content: [{ type: "output_text", text: combinedText }],
-			status: "completed",
-		};
-		output.push(msgItem);
-	}
-
-	let fcIndex = 0;
-	for (const block of toolBlocks) {
-		if (block.type !== "tool_use") continue;
-		const fcItem: OutputFunctionCallItem = {
-			type: "function_call",
-			id: `${responseId}_fc_${fcIndex}`,
-			call_id: block.id,
-			name: block.name,
-			arguments: JSON.stringify(block.input),
-			status: "completed",
-		};
-		output.push(fcItem);
-		fcIndex++;
+	let outputIdx = 0;
+	for (const block of resp.content) {
+		if (block.type === "text") {
+			const msgItem: OutputMessageItem = {
+				type: "message",
+				id: `${responseId}_msg_${outputIdx}`,
+				role: "assistant",
+				content: [{ type: "output_text", text: block.text }],
+				status: "completed",
+			};
+			output.push(msgItem);
+			outputIdx++;
+		} else if (block.type === "tool_use") {
+			const fcItem: OutputFunctionCallItem = {
+				type: "function_call",
+				id: `${responseId}_fc_${outputIdx}`,
+				call_id: block.id,
+				name: block.name,
+				arguments: JSON.stringify(block.input),
+				status: "completed",
+			};
+			output.push(fcItem);
+			outputIdx++;
+		}
 	}
 
 	return {

packages/openai-responses-adapter/src/stream-translator.ts

@@ -178,6 +178,13 @@ function processEvent(
 
 		if (state.textByBlock.has(blockIndex)) {
 			const fullText = state.textByBlock.get(blockIndex) ?? "";
+			emitSse(controller, "response.output_text.done", {
+				type: "response.output_text.done",
+				item_id: `${state.responseId}_msg_${outputIdx}`,
+				output_index: outputIdx,
+				content_index: outputIdx,
+				text: fullText,
+			});
 			const doneItem: Record<string, unknown> = {
 				type: "message",
 				id: `${state.responseId}_msg_${outputIdx}`,
@@ -193,6 +200,12 @@ function processEvent(
 			});
 		} else if (state.toolByBlock.has(blockIndex)) {
 			const tool = state.toolByBlock.get(blockIndex)!;
+			emitSse(controller, "response.function_call_arguments.done", {
+				type: "response.function_call_arguments.done",
+				item_id: `${state.responseId}_fc_${outputIdx}`,
+				output_index: outputIdx,
+				arguments: tool.argsBuf,
+			});
 			const doneItem: Record<string, unknown> = {
 				type: "function_call",
 				id: `${state.responseId}_fc_${outputIdx}`,