Email API for
AI agents

import { openai } from '@ai-sdk/openai'
import { generateObject } from 'ai'
import AIInbx from 'aiinbx'
import {
  createNextRouteHandler,
  emailToLLMString,
  threadToLLMString,
} from 'aiinbx/helpers'
import z from 'zod'

const infoAboutOurCompany = "...";

const aiInbx = new AIInbx();

export const POST = createNextRouteHandler({
  onInboundEmail: async ({ payload }) => {
    const { email } = payload.data;

    // Get the full conversation thread with all emails in the thread
    const thread = await aiInbx.threads.retrieve(email.threadId);

    const { object } = await generateObject({
      model: openai('gpt-5-mini'),
      schema: z.object({
        responseHtml: z.string(),
      }),
      system: `You are a helpful assistant that answers emails from customers. Here is everything you need to know about us: ${infoAboutOurCompany}`,
      prompt: `Here is the full conversation: ${threadToLLMString(thread)}

Please answer the latest inbound email as a human would.`,
    });

    await aiInbx.emails.reply(email.id, {
      from: 'support@your-domain.com',
      html: object.responseHtml,
    });

    return Response.json({ sent: true });
  },
});