Fix streaming for z-ai in anthropic provider, add preliminary support for tool call streaming. Only reporting argument string deltas, not partial JSON objects

packages/ai/test/generate.test.ts

@@ -5,7 +5,7 @@ import { fileURLToPath } from "url";
 import { afterAll, beforeAll, describe, expect, it } from "vitest";
 import { complete, stream } from "../src/generate.js";
 import { getModel } from "../src/models.js";
-import type { Api, Context, ImageContent, Model, OptionsForApi, Tool } from "../src/types.js";
+import type { Api, Context, ImageContent, Model, OptionsForApi, Tool, ToolResultMessage } from "../src/types.js";
 
 const __filename = fileURLToPath(import.meta.url);
 const __dirname = dirname(__filename);
@@ -70,13 +70,62 @@ async function handleToolCall<TApi extends Api>(model: Model<TApi>, options?: Op
 		tools: [calculatorTool],
 	};
 
-	const response = await complete(model, context, options);
+	const s = await stream(model, context, options);
+	let hasToolStart = false;
+	let hasToolDelta = false;
+	let hasToolEnd = false;
+	let accumulatedToolArgs = "";
+	let index = 0;
+	for await (const event of s) {
+		if (event.type === "toolcall_start") {
+			hasToolStart = true;
+			const toolCall = event.partial.content[event.contentIndex];
+			index = event.contentIndex;
+			expect(toolCall.type).toBe("toolCall");
+			if (toolCall.type === "toolCall") {
+				expect(toolCall.name).toBe("calculator");
+				expect(toolCall.id).toBeTruthy();
+			}
+		}
+		if (event.type === "toolcall_delta") {
+			hasToolDelta = true;
+			const toolCall = event.partial.content[event.contentIndex];
+			expect(event.contentIndex).toBe(index);
+			expect(toolCall.type).toBe("toolCall");
+			if (toolCall.type === "toolCall") {
+				expect(toolCall.name).toBe("calculator");
+				accumulatedToolArgs += event.delta;
+			}
+		}
+		if (event.type === "toolcall_end") {
+			hasToolEnd = true;
+			const toolCall = event.partial.content[event.contentIndex];
+			expect(event.contentIndex).toBe(index);
+			expect(toolCall.type).toBe("toolCall");
+			if (toolCall.type === "toolCall") {
+				expect(toolCall.name).toBe("calculator");
+				JSON.parse(accumulatedToolArgs);
+				expect(toolCall.arguments).not.toBeUndefined();
+				expect((toolCall.arguments as any).a).toBe(15);
+				expect((toolCall.arguments as any).b).toBe(27);
+				expect((toolCall.arguments as any).operation).oneOf(["add", "subtract", "multiply", "divide"]);
+			}
+		}
+	}
+
+	expect(hasToolStart).toBe(true);
+	expect(hasToolDelta).toBe(true);
+	expect(hasToolEnd).toBe(true);
+
+	const response = await s.result();
 	expect(response.stopReason).toBe("toolUse");
 	expect(response.content.some((b) => b.type === "toolCall")).toBeTruthy();
 	const toolCall = response.content.find((b) => b.type === "toolCall");
 	if (toolCall && toolCall.type === "toolCall") {
 		expect(toolCall.name).toBe("calculator");
 		expect(toolCall.id).toBeTruthy();
+	} else {
+		throw new Error("No tool call found in response");
 	}
 }
 
@@ -101,7 +150,7 @@ async function handleStreaming<TApi extends Api>(model: Model<TApi>, options?: O
 		}
 	}
 
-	const response = await s.finalMessage();
+	const response = await s.result();
 
 	expect(textStarted).toBe(true);
 	expect(textChunks.length).toBeGreaterThan(0);
@@ -135,7 +184,7 @@ async function handleThinking<TApi extends Api>(model: Model<TApi>, options?: Op
 		}
 	}
 
-	const response = await s.finalMessage();
+	const response = await s.result();
 
 	expect(response.stopReason, `Error: ${response.error}`).toBe("stop");
 	expect(thinkingStarted).toBe(true);
@@ -214,6 +263,7 @@ async function multiTurn<TApi extends Api>(model: Model<TApi>, options?: Options
 		context.messages.push(response);
 
 		// Process content blocks
+		const results: ToolResultMessage[] = [];
 		for (const block of response.content) {
 			if (block.type === "text") {
 				allTextContent += block.text;
@@ -241,15 +291,16 @@ async function multiTurn<TApi extends Api>(model: Model<TApi>, options?: Options
 				}
 
 				// Add tool result to context
-				context.messages.push({
+				results.push({
 					role: "toolResult",
 					toolCallId: block.id,
 					toolName: block.name,
-					content: `${result}`,
+					output: `${result}`,
 					isError: false,
 				});
 			}
 		}
+		context.messages.push(...results);
 
 		// If we got a stop response with text content, we're likely done
 		expect(response.stopReason).not.toBe("error");
@@ -331,12 +382,12 @@ describe("Generate E2E Tests", () => {
 			await handleStreaming(llm);
 		});
 
-		it("should handle ", { retry: 2 }, async () => {
-			await handleThinking(llm, { reasoningEffort: "medium" });
+		it("should handle thinking", { retry: 2 }, async () => {
+			await handleThinking(llm, { reasoningEffort: "high" });
 		});
 
 		it("should handle multi-turn with thinking and tools", async () => {
-			await multiTurn(llm, { reasoningEffort: "medium" });
+			await multiTurn(llm, { reasoningEffort: "high" });
 		});
 
 		it("should handle image input", async () => {