fix(prompt): parameters.model is now a string and is optional. It defaults to gpt-4 (#53)

- **fix(types): `ModelName` is a string now**
- **docs(README): `model` parameter is no longer required for
`prompt()`. It defaults to `gpt-4`**
- **fix: `model` parameter is now optional for `prompt()`. It defaults
to `gpt-4`**

Author: gr2m

README.md

@@ -45,7 +45,6 @@ import { prompt } from "@copilot-extensions/preview-sdk";
 
 try {
   const { message } = await prompt("What is the capital of France?", {
-    model: "gpt-4",
     token: process.env.TOKEN,
   });
 

index.d.ts

@@ -256,21 +256,12 @@ export interface GetUserConfirmationInterface {
 
 /** 
  * model names supported by Copilot API
- * 
- * Based on https://api.githubcopilot.com/models from 2024-09-02
+ * A list of currently supported models can be retrieved at
+ * https://api.githubcopilot.com/models. We set `ModelName` to `string` 
+ * instead of a union of the supported models as we cannot give
+ * guarantees about the supported models in the future.
  */
-export type ModelName =
-  | "gpt-3.5-turbo"
-  | "gpt-3.5-turbo-0613"
-  | "gpt-4"
-  | "gpt-4-0613"
-  | "gpt-4-o-preview"
-  | "gpt-4o"
-  | "gpt-4o-2024-05-13"
-  | "text-embedding-3-small"
-  | "text-embedding-3-small-inference"
-  | "text-embedding-ada-002"
-  | "text-embedding-ada-002-index"
+export type ModelName = string
 
 export interface PromptFunction {
   type: "function"
@@ -284,7 +275,7 @@ export interface PromptFunction {
 }
 
 export type PromptOptions = {
-  model: ModelName
+  model?: ModelName
   token: string
   tools?: PromptFunction[]
   messages?: InteropMessage[]

index.test-d.ts

@@ -291,9 +291,6 @@ export async function promptTest() {
   // @ts-expect-error - 2nd argument is required
   prompt("What is the capital of France?")
 
-  // @ts-expect-error - model argument is required
-  prompt("What is the capital of France?", { token: "" })
-
   // @ts-expect-error - token argument is required
   prompt("What is the capital of France?", { model: "" })
 }

lib/prompt.js

@@ -5,6 +5,7 @@ export async function prompt(userPrompt, promptOptions) {
   const options = typeof userPrompt === "string" ? promptOptions : userPrompt;
 
   const promptFetch = options.request?.fetch || fetch;
+  const modelName = options.model || "gpt-4";
 
   const systemMessage = options.tools
     ? "You are a helpful assistant. Use the supplied tools to assist the user."
@@ -40,7 +41,7 @@ export async function prompt(userPrompt, promptOptions) {
       },
       body: JSON.stringify({
         messages: messages,
-        model: options.model,
+        model: modelName,
         toolChoice: options.tools ? "auto" : undefined,
         tools: options.tools,
       }),

test/prompt.test.js

@@ -58,7 +58,67 @@ suite("prompt", () => {
 
     const result = await prompt("What is the capital of France?", {
       token: "secret",
-      model: "gpt-4",
+      request: { fetch: fetchMock },
+    });
+
+    t.assert.deepEqual(result, {
+      requestId: "<request-id>",
+      message: {
+        content: "<response text>",
+      },
+    });
+  });
+
+  test("options.prompt", async (t) => {
+    const mockAgent = new MockAgent();
+    function fetchMock(url, opts) {
+      opts ||= {};
+      opts.dispatcher = mockAgent;
+      return fetch(url, opts);
+    }
+
+    mockAgent.disableNetConnect();
+    const mockPool = mockAgent.get("https://api.githubcopilot.com");
+    mockPool
+      .intercept({
+        method: "post",
+        path: `/chat/completions`,
+        body: JSON.stringify({
+          messages: [
+            { role: "system", content: "You are a helpful assistant." },
+            { role: "user", content: "What is the capital of France?" },
+            { role: "assistant", content: "The capital of France is Paris." },
+            { role: "user", content: "What about Spain?" },
+          ],
+          model: "<custom-model>",
+        }),
+      })
+      .reply(
+        200,
+        {
+          choices: [
+            {
+              message: {
+                content: "<response text>",
+              },
+            },
+          ],
+        },
+        {
+          headers: {
+            "content-type": "application/json",
+            "x-request-id": "<request-id>",
+          },
+        }
+      );
+
+    const result = await prompt("What about Spain?", {
+      model: "<custom-model>",
+      token: "secret",
+      messages: [
+        { role: "user", content: "What is the capital of France?" },
+        { role: "assistant", content: "The capital of France is Paris." },
+      ],
       request: { fetch: fetchMock },
     });
 
@@ -114,7 +174,6 @@ suite("prompt", () => {
       );
 
     const result = await prompt("What about Spain?", {
-      model: "gpt-4",
       token: "secret",
       messages: [
         { role: "user", content: "What is the capital of France?" },
@@ -175,7 +234,6 @@ suite("prompt", () => {
       );
 
     const result = await prompt({
-      model: "gpt-4",
       token: "secret",
       messages: [
         { role: "user", content: "What is the capital of France?" },
@@ -247,7 +305,6 @@ suite("prompt", () => {
 
     const result = await prompt("Call the function", {
       token: "secret",
-      model: "gpt-4",
       tools: [
         {
           type: "function",
@@ -305,7 +362,6 @@ suite("prompt", () => {
 
     const result = await prompt("What is the capital of France?", {
       token: "secret",
-      model: "gpt-4",
       request: { fetch: fetchMock },
     });