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13- Generate code in TypeScript or TSX
14- Add appropriate TypeScript types and interfaces for all data structures
15- Prefer official SDKs or libraries than writing API calls directly
16- Ask the user to supply API or library documentation if you are at all unsure about it
17- **Never bake in secrets into the code** - always use environment variables
18- Include comments explaining complex logic (avoid commenting obvious operations)
23### 1. HTTP Trigger
24
25- Create web APIs and endpoints
26- Handle HTTP requests and responses
27- Example structure:
173However, it's *extremely importing* to note that `parseProject` and other Standard Library utilities ONLY RUN ON THE SERVER.
174If you need access to this data on the client, run it in the server and pass it to the client by splicing it into the HTML page
175or by making an API request for it.
176
177## Val Town Platform Specifics
181- **AI Image:** To inline generate an AI image use: `<img src="https://maxm-imggenurl.web.val.run/the-description-of-your-image" />`
182- **Storage:** DO NOT use the Deno KV module for storage
183- **Browser APIs:** DO NOT use the `alert()`, `prompt()`, or `confirm()` methods
184- **Weather Data:** Use open-meteo for weather data (doesn't require API keys) unless otherwise specified
185- **View Source:** Add a view source link by importing & using `import.meta.url.replace("ems.sh", "val.town)"` (or passing this data to the client) and include `target="_top"` attribute
186- **Error Debugging:** Add `<script src="https://esm.town/v/std/catch"></script>` to HTML to capture client-side errors
187- **Error Handling:** Only use try...catch when there's a clear local resolution; Avoid catches that merely log or return 500s. Let errors bubble up with full context
188- **Environment Variables:** Use `Deno.env.get('keyname')` when you need to, but generally prefer APIs that don't require keys
189- **Imports:** Use `https://esm.sh` for npm and Deno dependencies to ensure compatibility on server and browser
190- **Storage Strategy:** Only use backend storage if explicitly required; prefer simple static client-side sites
224### Backend (Hono) Best Practices
225
226- Hono is the recommended API framework
227- Main entry point should be `backend/index.ts`
228- **Static asset serving:** Use the utility functions to read and serve project files:
248  });
249  ```
250- Create RESTful API routes for CRUD operations
251- Always include this snippet at the top-level Hono app to re-throwing errors to see full stack traces:
252  ```ts
285   - For files in the project, use `readFile` helpers
286
2875. **API Design:**
288   - `fetch` handler is the entry point for HTTP vals
289   - Run the Hono app with `export default app.fetch // This is the entry point for HTTP vals`

3    <meta charset="UTF-8" />
4    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
5    <link rel="preconnect" href="https://fonts.googleapis.com">
6    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
7    <link
8      href="https://fonts.googleapis.com/css2?family=Source+Sans+3:ital,wght@0,200..900;1,200..900&display=swap"
9      rel="stylesheet"
10    >

97
98export async function sendDailyBriefing(chatId?: string, today?: DateTime) {
99  // Get API keys from environment
100  const apiKey = Deno.env.get("ANTHROPIC_API_KEY");
101  const telegramToken = Deno.env.get("TELEGRAM_TOKEN");
102
106  }
107
108  if (!apiKey) {
109    console.error("Anthropic API key is not configured.");
110    return;
111  }
122
123  // Initialize Anthropic client
124  const anthropic = new Anthropic({ apiKey });
125
126  // Initialize Telegram bot
162
163  // disabled title for now, it seemes unnecessary...
164  // await bot.api.sendMessage(chatId, `*${title}*`, { parse_mode: "Markdown" });
165
166  // Then send the main content
169
170  if (content.length <= MAX_LENGTH) {
171    await bot.api.sendMessage(chatId, content, { parse_mode: "Markdown" });
172    // Store the briefing in chat history
173    await storeChatMessage(
198    // Send each chunk as a separate message and store in chat history
199    for (const chunk of chunks) {
200      await bot.api.sendMessage(chatId, chunk, { parse_mode: "Markdown" });
201      // Store each chunk in chat history
202      await storeChatMessage(

53You'll need to set up some environment variables to make it run.
54
55- `ANTHROPIC_API_KEY` for LLM calls
56- You'll need to follow [these instructions](https://docs.val.town/integrations/telegram/) to make a telegram bot, and set `TELEGRAM_TOKEN`. You'll also need to get a `TELEGRAM_CHAT_ID` in order to have the bot remember chat contents.
57- For the Google Calendar integration you'll need `GOOGLE_CALENDAR_ACCOUNT_ID` and `GOOGLE_CALENDAR_CALENDAR_ID`. See [these instuctions](https://www.val.town/v/stevekrouse/pipedream) for details.

8## Hono
9
10This app uses [Hono](https://hono.dev/) as the API framework. You can think of Hono as a replacement for [ExpressJS](https://expressjs.com/) that works in serverless environments like Val Town or Cloudflare Workers. If you come from Python or Ruby, Hono is also a lot like [Flask](https://github.com/pallets/flask) or [Sinatra](https://github.com/sinatra/sinatra), respectively.
11
12## Serving assets to the frontend
20### `index.html`
21
22The most complicated part of this backend API is serving index.html. In this app (like most apps) we serve it at the root, ie `GET /`. 
23
24We *bootstrap* `index.html` with some initial data from the server, so that it gets dynamically injected JSON data without having to make another round-trip request to the server to get that data on the frontend. This is a common pattern for client-side rendered apps.
25
26## CRUD API Routes
27
28This app has two CRUD API routes: for reading and inserting into the messages table. They both speak JSON, which is standard. They import their functions from `/backend/database/queries.ts`. These routes are called from the React app to refresh and update data.
29
30## Errors
31
32Hono and other API frameworks have a habit of swallowing up Errors. We turn off this default behavior by re-throwing errors, because we think most of the time you'll want to see the full stack trace instead of merely "Internal Server Error". You can customize how you want errors to appear.

8import { type Memory } from "../../shared/types.ts";
9
10const API_BASE = "/api/memories";
11const MEMORIES_PER_PAGE = 20;
12
71    setError(null);
72    try {
73      const response = await fetch(API_BASE);
74      if (!response.ok) {
75        throw new Error(`HTTP error! status: ${response.status}`);
100
101    try {
102      const response = await fetch(API_BASE, {
103        method: "POST",
104        headers: { "Content-Type": "application/json" },
123
124    try {
125      const response = await fetch(`${API_BASE}/${id}`, {
126        method: "DELETE",
127      });
155
156    try {
157      const response = await fetch(`${API_BASE}/${editingMemory.id}`, {
158        method: "PUT",
159        headers: { "Content-Type": "application/json" },

18});
19
20// --- API Routes for Memories ---
21
22// GET /api/memories - Retrieve all memories
23app.get("/api/memories", async (c) => {
24  const memories = await getAllMemories();
25  return c.json(memories);
26});
27
28// POST /api/memories - Create a new memory
29app.post("/api/memories", async (c) => {
30  const body = await c.req.json<Omit<Memory, "id">>();
31  if (!body.text) {
36});
37
38// PUT /api/memories/:id - Update an existing memory
39app.put("/api/memories/:id", async (c) => {
40  const id = c.req.param("id");
41  const body = await c.req.json<Partial<Omit<Memory, "id">>>();
58});
59
60// DELETE /api/memories/:id - Delete a memory
61app.delete("/api/memories/:id", async (c) => {
62  const id = c.req.param("id");
63  try {
75// --- Blob Image Serving Routes ---
76
77// GET /api/images/:filename - Serve images from blob storage
78app.get("/api/images/:filename", async (c) => {
79  const filename = c.req.param("filename");
80

12      type="image/svg+xml"
13    />
14    <link rel="preconnect" href="https://fonts.googleapis.com" />
15    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
16    <link
17      href="https://fonts.googleapis.com/css2?family=Pixelify+Sans:wght@400..700&display=swap"
18      rel="stylesheet"
19    />

85  console.log(e.text);
86
87  // Get Anthropic API key from environment
88  const apiKey = Deno.env.get("ANTHROPIC_API_KEY");
89  if (!apiKey) {
90    console.error("Anthropic API key is not configured for this val.");
91    return;
92  }
93
94  // Initialize Anthropic client
95  const anthropic = new Anthropic({ apiKey });
96
97  // Process each image attachment serially

92
93/**
94 * Format chat history for Anthropic API
95 */
96function formatChatHistoryForAI(history) {
321bot.on("message", async (ctx) => {
322  try {
323    // Get Anthropic API key from environment
324    const apiKey = Deno.env.get("ANTHROPIC_API_KEY");
325    if (!apiKey) {
326      console.error("Anthropic API key is not configured.");
327      ctx.reply(
328        "I apologize, but I'm not properly configured at the moment. Please inform the household administrator."
332
333    // Initialize Anthropic client
334    const anthropic = new Anthropic({ apiKey });
335
336    // Get message text and user info
502  // Set webhook if it is not set yet
503  if (!isEndpointSet) {
504    await bot.api.setWebhook(req.url, {
505      secret_token: SECRET_TOKEN,
506    });