Vercel AI SDK tool with Stophy | Stophy

Setup

npm install ai @ai-sdk/openai zod

Set OPENAI_API_KEY in your environment. STOPHY_API_KEY is optional for this example.

The Stophy tool

This function calls Google search and returns the results as JSON, limited to 5 so the model’s context stays small. It reads your key from STOPHY_API_KEY, and works without one.

stophy.ts

export async function stophySearch(query: string): Promise<string> {
  const headers: Record<string, string> = { "content-type": "application/json" };
  if (process.env.STOPHY_API_KEY) headers.authorization = `Bearer ${process.env.STOPHY_API_KEY}`;
  const response = await fetch("https://api.stophy.dev/v1/google/search", {
    method: "POST",
    headers,
    body: JSON.stringify({ query }),
  });
  const body = await response.json();
  if (!body.success) throw new Error(body.error.message);
  return JSON.stringify(body.data.results);
}

Use it as a tool

Wrap the search in tool(). stopWhen lets the model search, read the results, and answer, in up to five steps.

import { openai } from "@ai-sdk/openai";
import { generateText, stepCountIs, tool } from "ai";
import { z } from "zod";
import { stophySearch } from "./stophy";

const { text } = await generateText({
  model: openai("gpt-5-mini"),
  prompt: "What changed in the latest Bun release?",
  tools: {
    webSearch: tool({
      description: "Search the web. Returns the top results as JSON.",
      inputSchema: z.object({ query: z.string().describe("What to search for") }),
      execute: async ({ query }) => stophySearch(query),
    }),
  },
  stopWhen: stepCountIs(5),
});

console.log(text);