fix assistant tool continuation

apps/nextjs/src/app/api/assistant/chat/assistant-tool-loop.spec.ts

@@ -0,0 +1,103 @@
+import { describe, expect, test, vi } from "vitest";
+import { jsonSchema, simulateReadableStream, stepCountIs, streamText, tool } from "ai";
+import { MockLanguageModelV4 } from "ai/test";
+
+const usage = {
+  inputTokens: { total: 10, noCache: 10, cacheRead: 0, cacheWrite: 0 },
+  outputTokens: { total: 5, text: 5, reasoning: 0 },
+};
+
+const finish = (unified: "stop" | "tool-calls") => ({
+  type: "finish" as const,
+  finishReason: { unified, raw: unified },
+  usage,
+});
+
+describe("Assistant tool loop", () => {
+  test("keeps a valid icon search alongside another agent tool result", async () => {
+    const findIcons = vi.fn(() => ({
+      countIcons: 1,
+      icons: [
+        {
+          slug: "homarr-labs/dashboard-icons",
+          icons: [{ name: "homarr.svg", url: "https://cdn.example.com/homarr.svg" }],
+        },
+      ],
+    }));
+    const getBoardSettings = vi.fn(() => ({ id: "board-1", name: "Home" }));
+    const model = new MockLanguageModelV4({
+      doStream: [
+        {
+          stream: simulateReadableStream({
+            chunks: [
+              { type: "stream-start" as const, warnings: [] },
+              {
+                type: "tool-call" as const,
+                toolCallId: "icon-call",
+                toolName: "icon_findIcons",
+                input: '{"searchText":"homarr"}',
+              },
+              {
+                type: "tool-call" as const,
+                toolCallId: "board-call",
+                toolName: "board_getBoardSettings",
+                input: '{"id":"board-1"}',
+              },
+              finish("tool-calls"),
+            ],
+            chunkDelayInMs: null,
+          }),
+        },
+        {
+          stream: simulateReadableStream({
+            chunks: [
+              { type: "stream-start" as const, warnings: [] },
+              { type: "text-start" as const, id: "answer" },
+              { type: "text-delta" as const, id: "answer", delta: "Both tools completed." },
+              { type: "text-end" as const, id: "answer" },
+              finish("stop"),
+            ],
+            chunkDelayInMs: null,
+          }),
+        },
+      ],
+    });
+    const result = streamText({
+      model,
+      prompt: "Find the Homarr icon and inspect my board.",
+      tools: {
+        icon_findIcons: tool({
+          inputSchema: jsonSchema({
+            type: "object",
+            properties: {
+              searchText: { type: "string" },
+              limitPerGroup: { type: "number", minimum: 1, maximum: 500, default: 12 },
+            },
+            additionalProperties: false,
+          }),
+          execute: findIcons,
+        }),
+        board_getBoardSettings: tool({
+          inputSchema: jsonSchema({
+            type: "object",
+            properties: { id: { type: "string" } },
+            required: ["id"],
+            additionalProperties: false,
+          }),
+          execute: getBoardSettings,
+        }),
+      },
+      stopWhen: stepCountIs(2),
+    });
+
+    await expect(result.text).resolves.toBe("Both tools completed.");
+    expect(findIcons).toHaveBeenCalledWith(
+      { searchText: "homarr" },
+      expect.objectContaining({ toolCallId: "icon-call" }),
+    );
+    expect(getBoardSettings).toHaveBeenCalledTimes(1);
+    const nextPrompt = JSON.stringify(model.doStreamCalls[1]?.prompt);
+    expect(nextPrompt).toContain("homarr.svg");
+    expect(nextPrompt).toContain('"id":"board-1"');
+  });
+});