Remove tools schema from request when reaching last step

[wangwalton]

Feature Description

There's no point to submitting tools as part of request in the last step (i.e. reaching maxSteps). It just eats up tokens.

import { generateText, tool } from "ai";
import { deepseek } from "@ai-sdk/deepseek";
import { z } from "zod";

export const weatherTool = tool({
  description: "Get the weather in a location",
  parameters: z.object({
    location: z.string().describe("The location to get the weather for"),
  }),

  execute: async ({ location }) => {
    console.log("weatherTool", { location });
    return {
      location,
      temperature: 72 + Math.floor(Math.random() * 21) - 10,
    };
  },
});

const main = async () => {
  const resp = await generateText({
    model: deepseek("deepseek-chat"),
    prompt: "what's the temp for seattle and sf and vancouver and toronto?",
    maxSteps: 2,
    tools: { weatherTool },
  });

  console.log(JSON.parse(resp.steps[1].request.body).tools);
};

main();

Outputs:

{type: 'function', function: {…}}

Use Cases

It would save significant tokens as most use cases only need maxSteps = 2, and if you have a big schema, it uses a lot of tokens.

Additional context

No response

[lgrammel]

you can use prepareStep and activeTools for this in ai sdk 5