Google Calendar connection via Google's hosted MCP server

app/.dev.vars.example

@@ -13,3 +13,8 @@ SESSION_SECRET=""
 # OIT API store credentials (ActiveDirectory subscription) for alias->netid.
 OIT_CONSUMER_KEY=""
 OIT_CONSUMER_SECRET=""
+# Google Calendar MCP (dev needs its own OAuth client with a
+# http://localhost:5173/oauth/google/callback redirect URI).
+GOOGLE_OAUTH_CLIENT_ID=""
+GOOGLE_OAUTH_CLIENT_SECRET=""
+APP_ORIGIN=""

app/README.md

@@ -48,6 +48,14 @@ browser (React + useAgentChat over WebSocket)
   full-page weekly Planner, an Agenda, and My apps. Design system in
   `src/client/styles.css`; official TigerApps logos in `public/logos/`.
 
+- **Google Calendar**: connects to Google's hosted Calendar MCP server with
+  read-only scopes via OAuth (`src/server/gcal.ts`). The client is
+  pre-registered in Google Cloud; consent runs once from *My apps* against
+  the user's desk DO, which stores the tokens and shares them with that
+  user's chats. Requires the `GOOGLE_OAUTH_CLIENT_ID` var, the
+  `GOOGLE_OAUTH_CLIENT_SECRET` secret, and an authorized redirect URI of
+  `<origin>/oauth/google/callback` on the OAuth client.
+
 ## Develop
 
 ```bash

app/src/client/lib/desk.ts

@@ -6,6 +6,7 @@ import { userInstance } from "./auth";
 export type DeskState = {
   settings: PiSettings | null;
   appErrors: Partial<Record<AppKey, string>>;
+  authUrls?: Partial<Record<AppKey, string>>;
 };
 
 export type McpServersSnapshot = {

app/src/client/lib/tools.ts

@@ -485,4 +485,5 @@ export const APP_INK: Record<AppKey, string> = {
   princetoncourses: "var(--hl-orange)",
   path: "var(--hl-violet)",
   snatch: "var(--hl-pink)",
+  gcal: "var(--hl-mint)",
 };

app/src/client/pages/AppsPage.tsx

@@ -41,6 +41,9 @@ export function AppsPage({
   }
 
   function statusFor(key: AppKey): { text: string; cls: string } {
+    if (desk.deskState?.authUrls?.[key]) {
+      return { text: "one step left", cls: "status" };
+    }
     const err = desk.deskState?.appErrors?.[key];
     if (err) return { text: `couldn't connect — ${err}`, cls: "status err" };
     const server = desk.mcp?.servers?.[key];
@@ -109,6 +112,14 @@ export function AppsPage({
                 <p className="adetail">{app.detail}</p>
                 <div className="foot">
                   <span className={status.cls}>{status.text}</span>
+                  {on && desk.deskState?.authUrls?.[app.key] && (
+                    <a
+                      className="cta"
+                      href={desk.deskState.authUrls[app.key]}
+                    >
+                      Connect with Google →
+                    </a>
+                  )}
                   <button
                     className={on ? "toggle on" : "toggle"}
                     role="switch"