feat: cal ai (#10992)

Co-authored-by: nicktrn <55853254+nicktrn@users.noreply.github.com>
Co-authored-by: tedspare <ted.spare@gmail.com>
Co-authored-by: Alex van Andel <me@alexvanandel.com>

apps/ai/.env.example

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+BACKEND_URL=http://localhost:3002/api
+
+APP_ID=cal-ai
+APP_URL=http://localhost:3000/apps/cal-ai
+
+# Used to verify requests from sendgrid. You can generate a new one with: `openssl rand -hex 32`
+PARSE_KEY=
+
+OPENAI_API_KEY=
+
+# Optionally trace completions at https://smith.langchain.com
+# LANGCHAIN_TRACING_V2=true
+# LANGCHAIN_ENDPOINT=
+# LANGCHAIN_API_KEY=
+# LANGCHAIN_PROJECT=

apps/ai/README.md

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+# Cal.com Email Assistant
+
+Welcome to the first stage of Cal AI!
+
+This app lets you chat with your calendar via email:
+
+  - Turn informal emails into bookings eg. forward "wanna meet tmrw at 2pm?"
+  - List and rearrange your bookings eg. "Cancel my next meeting"
+  - Answer basic questions about your busiest times eg. "How does my Tuesday look?"
+
+The core logic is contained in [agent/route.ts](/apps/ai/src/app/api/agent/route.ts). Here, a [LangChain Agent Executor](https://docs.langchain.com/docs/components/agents/agent-executor) is tasked with following your instructions. Given your last-known timezone, working hours, and busy times, it attempts to CRUD your bookings.
+
+_The AI agent can only choose from a set of tools, without ever seeing your API key._
+
+Emails are cleaned and routed in [receive/route.ts](/apps/ai/src/app/api/receive/route.ts) using [MailParser](https://nodemailer.com/extras/mailparser/).
+
+Incoming emails are routed by email address. Addresses are verified by [DKIM record](https://support.google.com/a/answer/174124?hl=en), making it hard to spoof them.
+
+## Getting Started
+
+### Development
+
+If you haven't yet, please run the [root setup](/README.md) steps.
+
+Before running the app, please see [env.mjs](./src/env.mjs) for all required environment variables. You'll need:
+
+  - An [OpenAI API key](https://platform.openai.com/account/api-keys) with access to GPT-4
+  - A [SendGrid API key](https://app.sendgrid.com/settings/api_keys)
+  - A default sender email (for example, `ai@cal.dev`)
+  - The Cal AI's app ID and URL (see [add.ts](/packages/app-store/cal-ai/api/index.ts))
+
+To stand up the API and AI apps simultaneously, simply run `yarn dev:ai`.
+
+### Email Router
+
+To expose the AI app, run `ngrok http 3000` (or the AI app's port number) in a new terminal. You may need to install [nGrok](https://ngrok.com/).
+
+To forward incoming emails to the Node.js server, one option is to use [SendGrid's Inbound Parse Webhook](https://docs.sendgrid.com/for-developers/parsing-email/setting-up-the-inbound-parse-webhook).
+
+1.  [Sign up for an account](https://signup.sendgrid.com/)
+2.  Go to Settings > [Inbound Parse](https://app.sendgrid.com/settings/parse) > Add Host & URL.
+3.  For subdomain, use `<sub>.<domain>.com` for now, where `sub` can be any subdomain but `domain.com` will need to be verified via MX records in your environment variables, eg. on [Vercel](https://vercel.com/guides/how-to-add-vercel-environment-variables).
+4.  Use the nGrok URL from above as the **Destination URL**.
+5.  Activate "POST the raw, full MIME message".
+6.  Send an email to `<anyone>@ai.example.com`. You should see a ping on the nGrok listener and Node.js server.
+7.  Adjust the logic in [receive/route.ts](/apps/ai/src/app/api/receive/route.ts), save to hot-reload, and send another email to test the behaviour.
+
+Please feel free to improve any part of this architecture.

apps/ai/next-env.d.ts

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+/// <reference types="next" />
+/// <reference types="next/image-types/global" />
+
+// NOTE: This file should not be edited
+// see https://nextjs.org/docs/basic-features/typescript for more information.

apps/ai/next.config.js

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+const withBundleAnalyzer = require("@next/bundle-analyzer");
+
+const plugins = [];
+plugins.push(withBundleAnalyzer({ enabled: process.env.ANALYZE === "true" }));
+
+/** @type {import("next").NextConfig} */
+const nextConfig = {
+  i18n: {
+    defaultLocale: "en",
+    locales: ["en"],
+  },
+  reactStrictMode: true,
+};
+
+module.exports = () => plugins.reduce((acc, next) => next(acc), nextConfig);

apps/ai/package.json

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+{
+  "name": "@calcom/ai",
+  "version": "0.1.0",
+  "private": true,
+  "author": "Cal.com Inc.",
+  "dependencies": {
+    "@calcom/prisma": "*",
+    "@t3-oss/env-nextjs": "^0.6.1",
+    "langchain": "^0.0.131",
+    "mailparser": "^3.6.5",
+    "next": "^13.4.6",
+    "zod": "^3.20.2"
+  },
+  "devDependencies": {
+    "@types/mailparser": "^3.4.0",
+    "@types/node": "^20.5.1",
+    "typescript": "^4.9.4"
+  },
+  "scripts": {
+    "build": "next build",
+    "dev": "next dev -p 3005",
+    "format": "npx prettier . --write",
+    "lint": "eslint . --ext .ts,.js,.tsx,.jsx",
+    "lint:fix": "eslint . --ext .ts,.js,.tsx,.jsx --fix",
+    "start": "next start"
+  }
+}

apps/ai/src/app/api/agent/route.ts

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+import type { NextRequest } from "next/server";
+import { NextResponse } from "next/server";
+
+import agent from "../../../utils/agent";
+import sendEmail from "../../../utils/sendEmail";
+import { verifyParseKey } from "../../../utils/verifyParseKey";
+
+/**
+ * Launches a LangChain agent to process an incoming email,
+ * then sends the response to the user.
+ */
+export const POST = async (request: NextRequest) => {
+  const verified = verifyParseKey(request.url);
+
+  if (!verified) {
+    return new NextResponse("Unauthorized", { status: 401 });
+  }
+
+  const json = await request.json();
+
+  const { apiKey, userId, message, subject, user, replyTo } = json;
+
+  if ((!message && !subject) || !user) {
+    return new NextResponse("Missing fields", { status: 400 });
+  }
+
+  try {
+    const response = await agent(`${subject}\n\n${message}`, user, apiKey, userId);
+
+    // Send response to user
+    await sendEmail({
+      subject: `Re: ${subject}`,
+      text: response.replace(/(?:\r\n|\r|\n)/g, "\n"),
+      to: user.email,
+      from: replyTo,
+    });
+
+    return new NextResponse("ok");
+  } catch (error) {
+    return new NextResponse(
+      (error as Error).message || "Something went wrong. Please try again or reach out for help.",
+      { status: 500 }
+    );
+  }
+};

apps/ai/src/app/api/receive/route.ts

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+import type { ParsedMail, Source } from "mailparser";
+import { simpleParser } from "mailparser";
+import type { NextRequest } from "next/server";
+import { NextResponse } from "next/server";
+
+import prisma from "@calcom/prisma";
+
+import { env } from "../../../env.mjs";
+import { fetchAvailability } from "../../../tools/getAvailability";
+import { fetchEventTypes } from "../../../tools/getEventTypes";
+import getHostFromHeaders from "../../../utils/host";
+import now from "../../../utils/now";
+import sendEmail from "../../../utils/sendEmail";
+import { verifyParseKey } from "../../../utils/verifyParseKey";
+
+/**
+ * Verifies email signature and app authorization,
+ * then hands off to booking agent.
+ */
+export const POST = async (request: NextRequest) => {
+  const verified = verifyParseKey(request.url);
+
+  if (!verified) {
+    return new NextResponse("Unauthorized", { status: 401 });
+  }
+
+  const formData = await request.formData();
+  const body = Object.fromEntries(formData);
+
+  // body.dkim looks like {@domain-com.22222222.gappssmtp.com : pass}
+  const signature = (body.dkim as string).includes(" : pass");
+
+  const envelope = JSON.parse(body.envelope as string);
+
+  const aiEmail = envelope.to[0];
+
+  // Parse email from mixed MIME type
+  const parsed: ParsedMail = await simpleParser(body.email as Source);
+
+  if (!parsed.text && !parsed.subject) {
+    return new NextResponse("Email missing text and subject", { status: 400 });
+  }
+
+  const user = await prisma.user.findUnique({
+    select: {
+      email: true,
+      id: true,
+      credentials: {
+        select: {
+          appId: true,
+          key: true,
+        },
+      },
+    },
+    where: { email: envelope.from },
+  });
+
+  if (!signature || !user?.email || !user?.id) {
+    await sendEmail({
+      subject: `Re: ${body.subject}`,
+      text: "Sorry, you are not authorized to use this service. Please verify your email address and try again.",
+      to: user?.email || "",
+      from: aiEmail,
+    });
+
+    return new NextResponse();
+  }
+
+  const credential = user.credentials.find((c) => c.appId === env.APP_ID)?.key;
+
+  // User has not installed the app from the app store. Direct them to install it.
+  if (!(credential as { apiKey: string })?.apiKey) {
+    const url = env.APP_URL;
+
+    await sendEmail({
+      html: `Thanks for using Cal AI! To get started, the app must be installed. <a href=${url} target="_blank">Click this link</a> to install it.`,
+      subject: `Re: ${body.subject}`,
+      text: `Thanks for using Cal AI! To get started, the app must be installed. Click this link to install the Cal AI app: ${url}`,
+      to: envelope.from,
+      from: aiEmail,
+    });
+
+    return new NextResponse("ok");
+  }
+
+  const { apiKey } = credential as { apiKey: string };
+
+  // Pre-fetch data relevant to most bookings.
+  const [eventTypes, availability] = await Promise.all([
+    fetchEventTypes({
+      apiKey,
+    }),
+    fetchAvailability({
+      apiKey,
+      userId: user.id,
+      dateFrom: now,
+      dateTo: now,
+    }),
+  ]);
+
+  if ("error" in availability) {
+    await sendEmail({
+      subject: `Re: ${body.subject}`,
+      text: "Sorry, there was an error fetching your availability. Please try again.",
+      to: user.email,
+      from: aiEmail,
+    });
+    console.error(availability.error);
+    return new NextResponse("Error fetching availability. Please try again.", { status: 400 });
+  }
+
+  if ("error" in eventTypes) {
+    await sendEmail({
+      subject: `Re: ${body.subject}`,
+      text: "Sorry, there was an error fetching your event types. Please try again.",
+      to: user.email,
+      from: aiEmail,
+    });
+    console.error(eventTypes.error);
+    return new NextResponse("Error fetching event types. Please try again.", { status: 400 });
+  }
+
+  const { timeZone, workingHours } = availability;
+
+  const appHost = getHostFromHeaders(request.headers);
+
+  // Hand off to long-running agent endpoint to handle the email. (don't await)
+  fetch(`${appHost}/api/agent?parseKey=${env.PARSE_KEY}`, {
+    body: JSON.stringify({
+      apiKey,
+      userId: user.id,
+      message: parsed.text,
+      subject: parsed.subject,
+      replyTo: aiEmail,
+      user: {
+        email: user.email,
+        eventTypes,
+        timeZone,
+        workingHours,
+      },
+    }),
+    headers: {
+      "Content-Type": "application/json",
+    },
+    method: "POST",
+  });
+
+  await new Promise((r) => setTimeout(r, 1000));
+
+  return new NextResponse("ok");
+};

apps/ai/src/env.mjs

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+import { createEnv } from "@t3-oss/env-nextjs";
+import { z } from "zod";
+
+export const env = createEnv({
+  /**
+   * Specify your client-side environment variables schema here. This way you can ensure the app
+   * isn't built with invalid env vars. To expose them to the client, prefix them with
+   * `NEXT_PUBLIC_`.
+   */
+  client: {
+    // NEXT_PUBLIC_CLIENTVAR: z.string().min(1),
+  },
+
+  /**
+   * You can't destruct `process.env` as a regular object in the Next.js edge runtimes (e.g.
+   * middlewares) or client-side so we need to destruct manually.
+   */
+  runtimeEnv: {
+    BACKEND_URL: process.env.BACKEND_URL,
+    APP_ID: process.env.APP_ID,
+    APP_URL: process.env.APP_URL,
+    PARSE_KEY: process.env.PARSE_KEY,
+    NODE_ENV: process.env.NODE_ENV,
+    OPENAI_API_KEY: process.env.OPENAI_API_KEY,
+    SENDGRID_API_KEY: process.env.SENDGRID_API_KEY,
+  },
+
+  /**
+   * Specify your server-side environment variables schema here. This way you can ensure the app
+   * isn't built with invalid env vars.
+   */
+  server: {
+    BACKEND_URL: z.string().url(),
+    APP_ID: z.string().min(1),
+    APP_URL: z.string().url(),
+    PARSE_KEY: z.string().min(1),
+    NODE_ENV: z.enum(["development", "test", "production"]),
+    OPENAI_API_KEY: z.string().min(1),
+    SENDGRID_API_KEY: z.string().min(1),
+  },
+});

apps/ai/src/tools/createBookingIfAvailable.ts

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+import { DynamicStructuredTool } from "langchain/tools";
+import { z } from "zod";
+
+import { env } from "../env.mjs";
+
+/**
+ * Creates a booking for a user by event type, times, and timezone.
+ */
+const createBooking = async ({
+  apiKey,
+  userId,
+  eventTypeId,
+  start,
+  end,
+  timeZone,
+  language,
+  responses,
+}: {
+  apiKey: string;
+  userId: number;
+  eventTypeId: number;
+  start: string;
+  end: string;
+  timeZone: string;
+  language: string;
+  responses: { name?: string; email?: string; location?: string };
+  title?: string;
+  status?: string;
+}): Promise<string | Error | { error: string }> => {
+  const params = {
+    apiKey,
+    userId: userId.toString(),
+  };
+
+  const urlParams = new URLSearchParams(params);
+
+  const url = `${env.BACKEND_URL}/bookings?${urlParams.toString()}`;
+
+  const response = await fetch(url, {
+    body: JSON.stringify({
+      end,
+      eventTypeId,
+      language,
+      metadata: {},
+      responses,
+      start,
+      timeZone,
+    }),
+    headers: {
+      "Content-Type": "application/json",
+    },
+    method: "POST",
+  });
+
+  if (response.status === 401) {
+    throw new Error("Unauthorized");
+  }
+
+  const data = await response.json();
+
+  if (response.status !== 200) {
+    return {
+      error: data.message,
+    };
+  }
+
+  return "Booking created";
+};
+
+const createBookingTool = (apiKey: string, userId: number) => {
+  return new DynamicStructuredTool({
+    description:
+      "Tries to create a booking. If the user is unavailable, it will return availability that day, allowing you to avoid the getAvailability step in many cases.",
+    func: async ({ eventTypeId, start, end, timeZone, language, responses, title, status }) => {
+      return JSON.stringify(
+        await createBooking({
+          apiKey,
+          userId,
+          end,
+          eventTypeId,
+          language,
+          responses,
+          start,
+          status,
+          timeZone,
+          title,
+        })
+      );
+    },
+    name: "createBookingIfAvailable",
+    schema: z.object({
+      end: z
+        .string()
+        .describe("This should correspond to the event type's length, unless otherwise specified."),
+      eventTypeId: z.number(),
+      language: z.string(),
+      responses: z
+        .object({
+          email: z.string().optional(),
+          name: z.string().optional(),
+        })
+        .describe("External invited user. Not the user making the request."),
+      start: z.string(),
+      status: z.string().optional().describe("ACCEPTED, PENDING, CANCELLED or REJECTED"),
+      timeZone: z.string(),
+      title: z.string().optional(),
+    }),
+  });
+};
+
+export default createBookingTool;

apps/ai/src/tools/deleteBooking.ts

@@ -0,0 +1,65 @@
+import { DynamicStructuredTool } from "langchain/tools";
+import { z } from "zod";
+
+import { env } from "../env.mjs";
+
+/**
+ * Cancels a booking for a user by ID with reason.
+ */
+const cancelBooking = async ({
+  apiKey,
+  id,
+  reason,
+}: {
+  apiKey: string;
+  id: string;
+  reason: string;
+}): Promise<string | { error: string }> => {
+  const params = {
+    apiKey,
+  };
+
+  const urlParams = new URLSearchParams(params);
+
+  const url = `${env.BACKEND_URL}/bookings/${id}/cancel?${urlParams.toString()}`;
+
+  const response = await fetch(url, {
+    body: JSON.stringify({ reason }),
+    headers: {
+      "Content-Type": "application/json",
+    },
+    method: "DELETE",
+  });
+
+  if (response.status === 401) throw new Error("Unauthorized");
+
+  const data = await response.json();
+
+  if (response.status !== 200) {
+    return { error: data.message };
+  }
+
+  return "Booking cancelled";
+};
+
+const cancelBookingTool = (apiKey: string) => {
+  return new DynamicStructuredTool({
+    description: "Cancel a booking",
+    func: async ({ id, reason }) => {
+      return JSON.stringify(
+        await cancelBooking({
+          apiKey,
+          id,
+          reason,
+        })
+      );
+    },
+    name: "cancelBooking",
+    schema: z.object({
+      id: z.string(),
+      reason: z.string(),
+    }),
+  });
+};
+
+export default cancelBookingTool;

apps/ai/src/tools/getAvailability.ts

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+import { DynamicStructuredTool } from "langchain/tools";
+import { z } from "zod";
+
+import { env } from "../env.mjs";
+import type { Availability } from "../types/availability";
+
+/**
+ * Fetches availability for a user by date range and event type.
+ */
+export const fetchAvailability = async ({
+  apiKey,
+  userId,
+  dateFrom,
+  dateTo,
+  eventTypeId,
+}: {
+  apiKey: string;
+  userId: number;
+  dateFrom: string;
+  dateTo: string;
+  eventTypeId?: number;
+}): Promise<Partial<Availability> | { error: string }> => {
+  const params: { [k: string]: string } = {
+    apiKey,
+    userId: userId.toString(),
+    dateFrom,
+    dateTo,
+  };
+
+  if (eventTypeId) params["eventTypeId"] = eventTypeId.toString();
+
+  const urlParams = new URLSearchParams(params);
+
+  const url = `${env.BACKEND_URL}/availability?${urlParams.toString()}`;
+
+  const response = await fetch(url);
+
+  if (response.status === 401) {
+    throw new Error("Unauthorized");
+  }
+
+  const data = await response.json();
+
+  if (response.status !== 200) {
+    return { error: data.message };
+  }
+
+  return {
+    busy: data.busy,
+    dateRanges: data.dateRanges,
+    timeZone: data.timeZone,
+    workingHours: data.workingHours,
+  };
+};
+
+const getAvailabilityTool = (apiKey: string, userId: number) => {
+  return new DynamicStructuredTool({
+    description: "Get availability within range.",
+    func: async ({ dateFrom, dateTo, eventTypeId }) => {
+      return JSON.stringify(
+        await fetchAvailability({
+          apiKey,
+          userId,
+          dateFrom,
+          dateTo,
+          eventTypeId,
+        })
+      );
+    },
+    name: "getAvailability",
+    schema: z.object({
+      dateFrom: z.string(),
+      dateTo: z.string(),
+      eventTypeId: z
+        .number()
+        .optional()
+        .describe(
+          "The ID of the event type to filter availability for if you've called getEventTypes, otherwise do not include."
+        ),
+    }),
+  });
+};
+
+export default getAvailabilityTool;

apps/ai/src/tools/getBookings.ts

@@ -0,0 +1,75 @@
+import { DynamicStructuredTool } from "langchain/tools";
+import { z } from "zod";
+
+import { env } from "../env.mjs";
+import type { Booking } from "../types/booking";
+import { BOOKING_STATUS } from "../types/booking";
+
+/**
+ * Fetches bookings for a user by date range.
+ */
+const fetchBookings = async ({
+  apiKey,
+  userId,
+  from,
+  to,
+}: {
+  apiKey: string;
+  userId: number;
+  from: string;
+  to: string;
+}): Promise<Booking[] | { error: string }> => {
+  const params = {
+    apiKey,
+    userId: userId.toString(),
+  };
+
+  const urlParams = new URLSearchParams(params);
+
+  const url = `${env.BACKEND_URL}/bookings?${urlParams.toString()}`;
+
+  const response = await fetch(url);
+
+  if (response.status === 401) throw new Error("Unauthorized");
+
+  const data = await response.json();
+
+  if (response.status !== 200) {
+    return { error: data.message };
+  }
+
+  const bookings: Booking[] = data.bookings
+    .filter((booking: Booking) => {
+      const afterFrom = new Date(booking.startTime).getTime() > new Date(from).getTime();
+      const beforeTo = new Date(booking.endTime).getTime() < new Date(to).getTime();
+      const notCancelled = booking.status !== BOOKING_STATUS.CANCELLED;
+
+      return afterFrom && beforeTo && notCancelled;
+    })
+    .map(({ endTime, eventTypeId, id, startTime, status, title }: Booking) => ({
+      endTime,
+      eventTypeId,
+      id,
+      startTime,
+      status,
+      title,
+    }));
+
+  return bookings;
+};
+
+const getBookingsTool = (apiKey: string, userId: number) => {
+  return new DynamicStructuredTool({
+    description: "Get bookings for a user between two dates.",
+    func: async ({ from, to }) => {
+      return JSON.stringify(await fetchBookings({ apiKey, userId, from, to }));
+    },
+    name: "getBookings",
+    schema: z.object({
+      from: z.string().describe("ISO 8601 datetime string"),
+      to: z.string().describe("ISO 8601 datetime string"),
+    }),
+  });
+};
+
+export default getBookingsTool;

apps/ai/src/tools/getEventTypes.ts

@@ -0,0 +1,51 @@
+import { DynamicStructuredTool } from "langchain/tools";
+import { z } from "zod";
+
+import { env } from "../env.mjs";
+import type { EventType } from "../types/eventType";
+
+/**
+ * Fetches event types by user ID.
+ */
+export const fetchEventTypes = async ({ apiKey }: { apiKey: string }) => {
+  const params = {
+    apiKey,
+  };
+
+  const urlParams = new URLSearchParams(params);
+
+  const url = `${env.BACKEND_URL}/event-types?${urlParams.toString()}`;
+
+  const response = await fetch(url);
+
+  if (response.status === 401) throw new Error("Unauthorized");
+
+  const data = await response.json();
+
+  if (response.status !== 200) {
+    return { error: data.message };
+  }
+
+  return data.event_types.map((eventType: EventType) => ({
+    id: eventType.id,
+    length: eventType.length,
+    title: eventType.title,
+  }));
+};
+
+const getEventTypesTool = (apiKey: string) => {
+  return new DynamicStructuredTool({
+    description: "Get the user's event type IDs. Usually necessary to book a meeting.",
+    func: async () => {
+      return JSON.stringify(
+        await fetchEventTypes({
+          apiKey,
+        })
+      );
+    },
+    name: "getEventTypes",
+    schema: z.object({}),
+  });
+};
+
+export default getEventTypesTool;

apps/ai/src/tools/updateBooking.ts

@@ -0,0 +1,84 @@
+import { DynamicStructuredTool } from "langchain/tools";
+import { z } from "zod";
+
+import { env } from "../env.mjs";
+
+/**
+ * Edits a booking for a user by booking ID with new times, title, description, or status.
+ */
+const editBooking = async ({
+  apiKey,
+  userId,
+  id,
+  startTime, // In the docs it says start, but it's startTime: https://cal.com/docs/enterprise-features/api/api-reference/bookings#edit-an-existing-booking.
+  endTime, // Same here: it says end but it's endTime.
+  title,
+  description,
+  status,
+}: {
+  apiKey: string;
+  userId: number;
+  id: string;
+  startTime?: string;
+  endTime?: string;
+  title?: string;
+  description?: string;
+  status?: string;
+}): Promise<string | { error: string }> => {
+  const params = {
+    apiKey,
+    userId: userId.toString(),
+  };
+  const urlParams = new URLSearchParams(params);
+
+  const url = `${env.BACKEND_URL}/bookings/${id}?${urlParams.toString()}`;
+
+  const response = await fetch(url, {
+    body: JSON.stringify({ description, endTime, startTime, status, title }),
+    headers: {
+      "Content-Type": "application/json",
+    },
+    method: "PATCH",
+  });
+
+  if (response.status === 401) throw new Error("Unauthorized");
+
+  const data = await response.json();
+
+  if (response.status !== 200) {
+    return { error: data.message };
+  }
+
+  return "Booking edited";
+};
+
+const editBookingTool = (apiKey: string, userId: number) => {
+  return new DynamicStructuredTool({
+    description: "Edit a booking",
+    func: async ({ description, endTime, id, startTime, status, title }) => {
+      return JSON.stringify(
+        await editBooking({
+          apiKey,
+          userId,
+          description,
+          endTime,
+          id,
+          startTime,
+          status,
+          title,
+        })
+      );
+    },
+    name: "editBooking",
+    schema: z.object({
+      description: z.string().optional(),
+      endTime: z.string().optional(),
+      id: z.string(),
+      startTime: z.string().optional(),
+      status: z.string().optional(),
+      title: z.string().optional(),
+    }),
+  });
+};
+
+export default editBookingTool;

apps/ai/src/types/availability.ts

@@ -0,0 +1,25 @@
+export type Availability = {
+  busy: {
+    start: string;
+    end: string;
+    title?: string;
+  }[];
+  timeZone: string;
+  dateRanges: {
+    start: string;
+    end: string;
+  }[];
+  workingHours: {
+    days: number[];
+    startTime: number;
+    endTime: number;
+    userId: number;
+  }[];
+  dateOverrides: {
+    date: string;
+    startTime: number;
+    endTime: number;
+    userId: number;
+  };
+  currentSeats: number;
+};

apps/ai/src/types/booking.ts

@@ -0,0 +1,23 @@
+export enum BOOKING_STATUS {
+  ACCEPTED = "ACCEPTED",
+  PENDING = "PENDING",
+  CANCELLED = "CANCELLED",
+  REJECTED = "REJECTED",
+}
+
+export type Booking = {
+  id: number;
+  userId: number;
+  description: string | null;
+  eventTypeId: number;
+  uid: string;
+  title: string;
+  startTime: string;
+  endTime: string;
+  attendees: { email: string; name: string; timeZone: string; locale: string }[] | null;
+  user: { email: string; name: string; timeZone: string; locale: string }[] | null;
+  payment: { id: number; success: boolean; paymentOption: string }[];
+  metadata: object | null;
+  status: BOOKING_STATUS;
+  responses: { email: string; name: string; location: string } | null;
+};

apps/ai/src/types/eventType.ts

@@ -0,0 +1,13 @@
+export type EventType = {
+  id: number;
+  title: string;
+  length: number;
+  metadata: object;
+  slug: string;
+  hosts: {
+    userId: number;
+    isFixed: boolean;
+  }[];
+  hidden: boolean;
+  // ...
+};

apps/ai/src/types/user.ts

@@ -0,0 +1,9 @@
+import type { EventType } from "./eventType";
+import type { WorkingHours } from "./workingHours";
+
+export type User = {
+  email: string;
+  timeZone: string;
+  eventTypes: EventType[];
+  workingHours: WorkingHours[];
+};

apps/ai/src/types/workingHours.ts

@@ -0,0 +1,5 @@
+export type WorkingHours = {
+  days: number[];
+  startTime: number;
+  endTime: number;
+};

apps/ai/src/utils/agent.ts

@@ -0,0 +1,73 @@
+import { initializeAgentExecutorWithOptions } from "langchain/agents";
+import { ChatOpenAI } from "langchain/chat_models/openai";
+
+import { env } from "../env.mjs";
+import createBookingIfAvailable from "../tools/createBookingIfAvailable";
+import deleteBooking from "../tools/deleteBooking";
+import getAvailability from "../tools/getAvailability";
+import getBookings from "../tools/getBookings";
+import updateBooking from "../tools/updateBooking";
+import type { EventType } from "../types/eventType";
+import type { User } from "../types/user";
+import type { WorkingHours } from "../types/workingHours";
+import now from "./now";
+
+const gptModel = "gpt-4";
+
+/**
+ * Core of the Cal AI booking agent: a LangChain Agent Executor.
+ * Uses a toolchain to book meetings, list available slots, etc.
+ * Uses OpenAI functions to better enforce JSON-parsable output from the LLM.
+ */
+const agent = async (input: string, user: User, apiKey: string, userId: number) => {
+  const tools = [
+    createBookingIfAvailable(apiKey, userId),
+    getAvailability(apiKey, userId),
+    getBookings(apiKey, userId),
+    updateBooking(apiKey, userId),
+    deleteBooking(apiKey),
+  ];
+
+  const model = new ChatOpenAI({
+    modelName: gptModel,
+    openAIApiKey: env.OPENAI_API_KEY,
+    temperature: 0,
+  });
+
+  /**
+   * Initialize the agent executor with arguments.
+   */
+  const executor = await initializeAgentExecutorWithOptions(tools, model, {
+    agentArgs: {
+      prefix: `You are Cal AI - a bleeding edge scheduling assistant that interfaces via email.
+            Make sure your final answers are definitive, complete and well formatted.
+            Sometimes, tools return errors. In this case, try to handle the error intelligently or ask the user for more information.
+            Tools will always handle times in UTC, but times sent to the user should be formatted per that user's timezone.
+
+            Current UTC time is: ${now}
+            The user's time zone is: ${user.timeZone}
+            The user's event types are: ${user.eventTypes
+              .map((e: EventType) => `ID: ${e.id}, Title: ${e.title}, Length: ${e.length}`)
+              .join("\n")}
+            The user's working hours are: ${user.workingHours
+              .map(
+                (w: WorkingHours) =>
+                  `Days: ${w.days.join(", ")}, Start Time (minutes in UTC): ${
+                    w.startTime
+                  }, End Time (minutes in UTC): ${w.endTime}`
+              )
+              .join("\n")}
+            `,
+    },
+    agentType: "openai-functions",
+    returnIntermediateSteps: env.NODE_ENV === "development",
+    verbose: env.NODE_ENV === "development",
+  });
+
+  const result = await executor.call({ input });
+  const { output } = result;
+
+  return output;
+};
+
+export default agent;

apps/ai/src/utils/host.ts

@@ -0,0 +1,7 @@
+import type { NextRequest } from "next/server";
+
+const getHostFromHeaders = (headers: NextRequest["headers"]): string => {
+  return `https://${headers.get("host")}`;
+};
+
+export default getHostFromHeaders;

apps/ai/src/utils/now.ts

@@ -0,0 +1 @@
+export default new Date().toISOString();

apps/ai/src/utils/sendEmail.ts

@@ -0,0 +1,40 @@
+import mail from "@sendgrid/mail";
+
+const sendgridAPIKey = process.env.SENDGRID_API_KEY as string;
+
+/**
+ * Simply send an email by address, subject, and body.
+ */
+const send = async ({
+  subject,
+  to,
+  from,
+  text,
+  html,
+}: {
+  subject: string;
+  to: string;
+  from: string;
+  text: string;
+  html?: string;
+}): Promise<boolean> => {
+  mail.setApiKey(sendgridAPIKey);
+
+  const msg = {
+    to,
+    from: {
+      email: from,
+      name: "Cal AI",
+    },
+    text,
+    html,
+    subject,
+  };
+
+  const res = await mail.send(msg);
+  const success = !!res;
+
+  return success;
+};
+
+export default send;

apps/ai/src/utils/verifyParseKey.ts

@@ -0,0 +1,13 @@
+import type { NextRequest } from "next/server";
+
+import { env } from "../env.mjs";
+
+/**
+ * Verifies that the request contains the correct parse key.
+ * env.PARSE_KEY must be configured as a query param in the sendgrid inbound parse settings.
+ */
+export const verifyParseKey = (url: NextRequest["url"]) => {
+  const verified = new URL(url).searchParams.get("parseKey") === env.PARSE_KEY;
+
+  return verified;
+};

apps/ai/tsconfig.json

@@ -0,0 +1,18 @@
+{
+  "extends": "@calcom/tsconfig/nextjs.json",
+  "compilerOptions": {
+    "strict": true,
+    "jsx": "preserve",
+    "baseUrl": ".",
+    "paths": {
+      "~/*": ["*"]
+    },
+    "plugins": [
+      {
+        "name": "next"
+      }
+    ]
+  },
+  "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx", ".next/types/**/*.ts"],
+  "exclude": ["node_modules"]
+}

package.json

@@ -30,6 +30,7 @@
     "db-studio": "yarn prisma studio",
     "deploy": "turbo run deploy",
     "dev:all": "turbo run dev --scope=\"@calcom/web\" --scope=\"@calcom/website\" --scope=\"@calcom/console\"",
+    "dev:ai": "turbo run dev --scope=\"@calcom/web\" --scope=\"@calcom/api\" --scope=\"@calcom/ai\"",
     "dev:api": "turbo run dev --scope=\"@calcom/web\" --scope=\"@calcom/api\"",
     "dev:api:console": "turbo run dev --scope=\"@calcom/web\" --scope=\"@calcom/api\" --scope=\"@calcom/console\"",
     "dev:console": "turbo run dev --scope=\"@calcom/web\" --scope=\"@calcom/console\"",

packages/app-store/apps.metadata.generated.ts

@@ -6,6 +6,7 @@ import amie_config_json from "./amie/config.json";
 import { metadata as applecalendar__metadata_ts } from "./applecalendar/_metadata";
 import around_config_json from "./around/config.json";
 import basecamp3_config_json from "./basecamp3/config.json";
+import cal_ai_config_json from "./cal-ai/config.json";
 import { metadata as caldavcalendar__metadata_ts } from "./caldavcalendar/_metadata";
 import campfire_config_json from "./campfire/config.json";
 import closecom_config_json from "./closecom/config.json";
@@ -75,6 +76,7 @@ export const appStoreMetadata = {
   applecalendar: applecalendar__metadata_ts,
   around: around_config_json,
   basecamp3: basecamp3_config_json,
+  "cal-ai": cal_ai_config_json,
   caldavcalendar: caldavcalendar__metadata_ts,
   campfire: campfire_config_json,
   closecom: closecom_config_json,

packages/app-store/apps.server.generated.ts

@@ -7,6 +7,7 @@ export const apiHandlers = {
   applecalendar: import("./applecalendar/api"),
   around: import("./around/api"),
   basecamp3: import("./basecamp3/api"),
+  "cal-ai": import("./cal-ai/api"),
   caldavcalendar: import("./caldavcalendar/api"),
   campfire: import("./campfire/api"),
   closecom: import("./closecom/api"),

packages/app-store/cal-ai/DESCRIPTION.md

@@ -0,0 +1,7 @@
+---
+items:
+  - 1.png
+  - 2.png
+---
+
+{DESCRIPTION}

packages/app-store/cal-ai/api/_getAdd.ts

@@ -0,0 +1,39 @@
+import type { NextApiRequest, NextApiResponse } from "next";
+
+import { defaultResponder } from "@calcom/lib/server";
+import { createContext } from "@calcom/trpc/server/createContext";
+import { viewerRouter } from "@calcom/trpc/server/routers/viewer/_router";
+
+import checkSession from "../../_utils/auth";
+import getInstalledAppPath from "../../_utils/getInstalledAppPath";
+import { checkInstalled, createDefaultInstallation } from "../../_utils/installation";
+import appConfig from "../config.json";
+
+export async function getHandler(req: NextApiRequest, res: NextApiResponse) {
+  const session = checkSession(req);
+  const slug = appConfig.slug;
+  const appType = appConfig.type;
+
+  const ctx = await createContext({ req, res });
+  const caller = viewerRouter.createCaller(ctx);
+
+  const apiKey = await caller.apiKeys.create({
+    note: "Cal AI",
+    expiresAt: null,
+    appId: "cal-ai",
+  });
+
+  await checkInstalled(slug, session.user.id);
+  await createDefaultInstallation({
+    appType,
+    userId: session.user.id,
+    slug,
+    key: {
+      apiKey,
+    },
+  });
+
+  return { url: getInstalledAppPath({ variant: appConfig.variant, slug: "cal-ai" }) };
+}
+
+export default defaultResponder(getHandler);

packages/app-store/cal-ai/api/add.ts

@@ -0,0 +1,5 @@
+import { defaultHandler } from "@calcom/lib/server";
+
+export default defaultHandler({
+  GET: import("./_getAdd"),
+});

packages/app-store/cal-ai/api/index.ts

@@ -0,0 +1 @@
+export { default as add } from "./add";

packages/app-store/cal-ai/config.json

@@ -0,0 +1,17 @@
+{
+  "/*": "Don't modify slug - If required, do it using cli edit command",
+  "name": "Cal AI",
+  "slug": "cal-ai",
+  "type": "cal-ai_automation",
+  "logo": "icon.png",
+  "url": "https://cal.ai",
+  "variant": "automation",
+  "categories": ["automation"],
+  "publisher": "Rubric Labs",
+  "email": "hi@cal.ai",
+  "description": "Cal AI is a scheduling assistant powered by GPT. Email hi@cal.ai to chat with your calendar or book, edit and cancel meetings.",
+  "isTemplate": false,
+  "__createdUsingCli": true,
+  "__template": "basic",
+  "dirName": "cal-ai"
+}

packages/app-store/cal-ai/index.ts

@@ -0,0 +1 @@
+export * as api from "./api";

packages/app-store/cal-ai/package.json

@@ -0,0 +1,14 @@
+{
+  "$schema": "https://json.schemastore.org/package.json",
+  "private": true,
+  "name": "@calcom/cal-ai",
+  "version": "0.0.0",
+  "main": "./index.ts",
+  "dependencies": {
+    "@calcom/lib": "*"
+  },
+  "devDependencies": {
+    "@calcom/types": "*"
+  },
+  "description": "Cal AI is a scheduling assistant powered by GPT. Email hi@cal.ai to chat with your calendar or book, edit and cancel meetings"
+}

turbo.json

@@ -45,6 +45,9 @@
       "cache": false,
       "dependsOn": []
     },
+    "@calcom/ai#build": {
+      "env": ["CAL_AI_DATABASE_URL", "BACKEND_URL", "APP_ID", "APP_URL", "OPENAI_API_KEY", "PARSE_KEY"]
+    },
     "@calcom/website#build": {
       "dependsOn": ["^build"],
       "outputs": [".next/**"],