Added streams section to readme

packages/evalite/readme.md

@@ -239,3 +239,30 @@ const result = await generateText({
 > [!NOTE]
 >
 > `traceAISDKModel`, like `reportTrace`, is a no-op in production.
+
+### Streams
+
+You can handle streams in Evalite by returning a `ReadableStream` from your task. This means you can test functions like the AI SDK `streamText` function easily:
+
+```ts
+import { evalite } from "evalite";
+import { streamText } from "ai";
+import { openai } from "@ai-sdk/openai";
+import { Factuality } from "autoevals";
+
+evalite("My Eval", {
+  data: async () => {
+    return [{ input: "What is the capital of France?", expected: "Paris" }];
+  },
+  task: async (input) => {
+    const result = await streamText({
+      model: openai("your-model"),
+      system: `Answer the question concisely.`,
+      prompt: input,
+    });
+
+    return result.textStream;
+  },
+  scorers: [Factuality],
+});
+```