Qwen3.8-27B-Fast

1,344 tokens: 100 read, 1,244 written · 1 min 23 s · 24 tok/s

Passes when One sentence of 5 to 30 words saying the library opens earlier (8 a.m.) on weekdays.

Summarize this in one sentence of at most 30 words.

Starting March 3, the Millbrook Public Library will open at 8 a.m. instead of 10 a.m. on weekdays. The change follows a survey in which 62% of respondents asked for earlier hours. Weekend hours stay the same. The library will hire two part-time staff to cover the extra time, paid for by a state grant.

Following a survey, the Millbrook Public Library will open at 8 a.m. instead of 10 a.m. on weekdays starting March 3, with two part-time staff funded by a state grant.

831 tokens: 194 read, 637 written · 27 s · 24.5 tok/s

Passes when Exactly three bullet points and nothing else, each at most 20 words, covering the launch moving to June 12, the approved marketing budget and Priya owning testing, and leaving out the webhook fix and the coffee machine.

Summarize these meeting notes as exactly three bullet points, each at most 20 words. Keep only the decisions and ownership changes that matter. Output only the bullet points.

Weekly sync, product team. Present: Priya, Omar, Jules, Sam.
- Omar reported that the payment provider fixed the webhook bug; no action needed.
- The launch date moves from June 5 to June 12 because the app store review is slow.
- Jules showed the new onboarding screens. Everyone liked them. Small copy changes only.
- The marketing budget of $40,000 was approved by finance on Monday.
- Priya will own end-to-end testing from now on; Sam hands over the test plan by Friday.
- Next sync is moved to Thursday at 10:00.
- Coffee machine on floor 3 is broken again.

- Launch date moves from June 5 to June 12 due to delayed app store review.
- Priya now owns end-to-end testing; Sam hands over the test plan by Friday.
- The $40,000 marketing budget was approved by finance.

348 tokens: 120 read, 228 written · 11 s · 23.5 tok/s

Passes when Both lines. Sentiment is mixed: the reviewer loves the battery and sound but is annoyed. The complaint names the charger or support in at most 12 words.

Read this product review and answer in exactly this format:
Sentiment: <positive, negative or mixed>
Complaint: <the main complaint in a few words>

I've used this speaker every day for a month. The battery is honestly amazing, easily two full days, and it sounds far better than its size suggests. But the charger that came in the box stopped working after a week, and support took nine days to reply. I bought a replacement cable myself. Would I buy it again? Probably, but I'm annoyed.

Sentiment: mixed
Complaint: defective charger and slow support response

1,220 tokens: 135 read, 1,085 written · 45 s · 24.5 tok/s

Passes when At most 50 words with the 240 participants, the 12-week length and the 3.1-day result, and nothing the text does not say (no approval, cure, children or recommendation).

Summarize this in at most 50 words. Keep the key numbers. Do not add anything the text does not say.

In a randomized trial, 240 adults with chronic migraine took either the new drug or a placebo for 12 weeks. Those on the drug had 3.1 fewer headache days per month on average, compared with 1.9 fewer days for placebo. Nausea was the most common side effect, reported by 9% of the drug group. The authors note the trial lasted only 12 weeks and call for longer studies before any recommendation is made.

In a randomized trial, 240 adults with chronic migraine took a new drug or placebo for 12 weeks. The drug group had 3.1 fewer headache days per month vs. 1.9 for placebo. Nausea affected 9% of the drug group. Authors call for longer studies given the 12-week duration.

647 tokens: 214 read, 433 written · 19 s · 24.4 tok/s

Passes when Exactly four lines of the form "- owner: action": Dana sends the contract, Luis books the venue, Mei updates the budget sheet, Dana emails the caterer. Tom's declined offer, the logo and the invitations are left out.

List every action item in this email thread that someone has committed to do, as lines of the form "- <owner>: <action>". Leave out offers that were declined and things that turned out not to be needed. Output only the list.

From: Dana
Hi all, quick recap of what's still open for the June offsite. I'll send the revised contract to the hotel by Wednesday.

From: Tom
I can book the venue for the dinner if that helps?

From: Luis
Thanks Tom, but I'll book the venue myself since I already spoke to them. Also, no need to change the logo on the badges, it's fine as is.

From: Mei
I'll update the budget sheet with the new hotel price tonight.

From: Dana
Great. Oh, and I'll email the caterer about the vegetarian options. Tom, could you just double-check the date on the invitations? Actually never mind, I checked them this morning, they're correct.

- Dana: Send the revised contract to the hotel by Wednesday
- Luis: Book the venue for the dinner
- Mei: Update the budget sheet with the new hotel price tonight
- Dana: Email the caterer about the vegetarian options

267 tokens: 118 read, 149 written · 7 s · 24.8 tok/s

Passes when Only a JSON object with exactly name "Laura Chen", company "Northwind Traders", meeting_date "2025-05-14" and attendees the number 4.

Extract these fields from the email as a JSON object with exactly these keys: "name" (the sender's full name), "company", "meeting_date" (YYYY-MM-DD) and "attendees" (a number). Output only the JSON.

Hello! This is Laura Chen from Northwind Traders. We'd love to visit your workshop. Could we meet on the 14th of May 2025, any time after lunch? We'll be four people in total, including me. Best, Laura

{"name":"Laura Chen","company":"Northwind Traders","meeting_date":"2025-05-14","attendees":4}

387 tokens: 139 read, 248 written · 11 s · 24.6 tok/s

Passes when Exactly four addresses, one per line, in order: info@harbor-events.org, speakers@harbor-events.org, mia.k@studio-nine.io, accounts@harbor-events.org. "jo at harbor dot org" is not written out in full, and its inbox is closed.

List every email address written out in full in this text (like name@example.com), one per line, in the order they first appear, without duplicates. Leave out any inbox the text says is closed. Output only the addresses.

Contacts for the conference: write to info@harbor-events.org for general questions, or to speakers@harbor-events.org if you are presenting. Our designer (mia.k@studio-nine.io) made the poster. Billing questions: accounts@harbor-events.org. Again, presenters use speakers@harbor-events.org. Please don't write to jo at harbor dot org, that inbox is closed.

info@harbor-events.org
speakers@harbor-events.org
mia.k@studio-nine.io
accounts@harbor-events.org

355 tokens: 98 read, 257 written · 11 s · 24.5 tok/s

Passes when The header item,qty,price, then the four items with whole-number quantities and prices as plain numbers (no $).

Convert this shopping list to CSV with the header row item,qty,price. Write prices as plain numbers without a currency sign. Output only the CSV.

Apples - 12 @ $0.50
Bread loaf - 2 @ $3.25
Olive oil (1 l) - 1 @ $8.90
Eggs - 18 @ $0.30

item,qty,price
Apples,12,0.50
Bread loaf,2,3.25
Olive oil (1 l),1,8.90
Eggs,18,0.30

185 tokens: 99 read, 86 written · 4 s · 25.4 tok/s

Passes when Only 2025-02-07, the extended deadline.

What is the final submission deadline? Answer with the date only, in YYYY-MM-DD format.

The call for papers opened on 2 January 2025. Drafts were originally due January 20, but the committee extended the final submission deadline to 7 February 2025. Reviews are due by 28 February, and results will be announced on March 10, 2025.

2025-02-07

619 tokens: 276 read, 343 written · 15 s · 25.2 tok/s

Passes when Only a JSON array of the WARN line and the two ERROR lines, in order, with time, level and message copied exactly.

From this log, return a JSON array with one object per WARN or ERROR line, in order, each with the keys "time" (HH:MM:SS), "level" and "message". Output only the JSON.

2025-03-04 09:12:01 INFO  server started on port 8080
2025-03-04 09:12:07 WARN  config key "timeout" is deprecated
2025-03-04 09:13:44 INFO  user alice logged in
2025-03-04 09:15:02 ERROR database connection lost
2025-03-04 09:15:03 INFO  retrying in 5s
2025-03-04 09:15:08 INFO  database reconnected
2025-03-04 09:20:30 DEBUG cache hit ratio 0.93
2025-03-04 09:31:12 ERROR payment webhook returned 502

[{"time":"09:12:07","level":"WARN","message":"config key \"timeout\" is deprecated"},{"time":"09:15:02","level":"ERROR","message":"database connection lost"},{"time":"09:31:12","level":"ERROR","message":"payment webhook returned 502"}]

68 tokens: 20 read, 48 written · 2 s · 25.1 tok/s

Passes when Exactly OK, with nothing else, not even a full stop.

Reply with exactly the word OK and nothing else.

OK

232 tokens: 42 read, 190 written · 8 s · 23.6 tok/s

Passes when Exactly three lines about the sea, all lowercase, the third ending with a question mark.

Write exactly three lines about the sea. Every line must be entirely lowercase, and the third line must end with a question mark. Output only the three lines.

the sea stretches endlessly toward the horizon
waves crash against the rocks with quiet force
will the tide ever carry you home?

139 tokens: 46 read, 93 written · 4 s · 25.1 tok/s

Passes when Only JSON with exactly two keys: colors (three lowercase color names) and count (the number 3).

Return a JSON object with exactly two keys: "colors", a list of exactly three color names in lowercase, and "count", the number 3. Output only the JSON.

{"colors": ["red", "green", "blue"], "count": 3}

153 tokens: 39 read, 114 written · 5 s · 24.5 tok/s

Passes when One line: apple, apricot, banana, cherry, pear (any capitalization).

Sort these words alphabetically, ignoring case, and output them on one line separated by commas: pear, Apple, banana, cherry, apricot

Apple, apricot, banana, cherry, pear

744 tokens: 46 read, 698 written · 29 s · 24.1 tok/s

Passes when Two words, both capitalized, with no letter e anywhere.

Suggest a product name for a solar-powered lamp. Rules: exactly two words, both capitalized, and the letter "e" must not appear anywhere. Output only the name.

Solar Glow

261 tokens: 52 read, 209 written · 9 s · 24.8 tok/s

A shop sells pencils at 2 for $0.90. How much do 15 pencils cost, in dollars? Work it out, then end with a line "ANSWER: <number>".

To find the cost of 15 pencils:

**Step 1:** Find the cost per pencil.
2 pencils = $0.90, so 1 pencil = $0.90 ÷ 2 = $0.45

**Step 2:** Multiply by 15 pencils.
15 × $0.45 = $6.75

ANSWER: 6.75

327 tokens: 46 read, 281 written · 12 s · 24.6 tok/s

Today is Tuesday. What day of the week will it be 190 days from today? Work it out, then end with a line "ANSWER: <day>".

To find the day of the week 190 days from Tuesday, I need to find the remainder when 190 is divided by 7 (the number of days in a week).

190 ÷ 7 = 27 remainder 1

(Since 7 × 27 = 189, and 190 − 189 = 1)

So 190 days from Tuesday is 1 day after Tuesday.

Tuesday + 1 day = **Wednesday**

ANSWER: Wednesday

268 tokens: 66 read, 202 written · 9 s · 24.4 tok/s

Kim, Jon and Ivy each own exactly one pet: a cat, a dog or a fish, all different. Kim does not own the dog. Ivy owns the fish. Who owns the cat? Work it out, then end with a line "ANSWER: <name>".

Working through the clues:

1. **Ivy owns the fish.** (given directly)
2. That leaves the **cat** and the **dog** for Kim and Jon.
3. **Kim does not own the dog**, so Kim must own the **cat**.
4. Jon owns the dog (by elimination).

ANSWER: Kim

272 tokens: 63 read, 209 written · 9 s · 25.2 tok/s

A train leaves at 17:35 and the trip takes 4 hours 5 minutes. At what time does it arrive? Work it out, then end with a line "ANSWER: <HH:MM>" in 24-hour time.

Starting at 17:35, I add the journey duration of 4 hours 5 minutes.

- Hours: 17 + 4 = 21
- Minutes: 35 + 5 = 40

So the train arrives at 21:40.

ANSWER: 21:40

477 tokens: 87 read, 390 written · 17 s · 24.4 tok/s

A tank holds 120 liters. Pipe A alone fills it in 6 hours, pipe B alone fills it in 2 hours, and a drain alone empties a full tank in 3 hours. With all three open and the tank starting empty, how many hours until it is full? Work it out, then end with a line "ANSWER: <number>".

## Setting Up the Rates

Each pipe's contribution, measured in liters per hour:

| Component | Rate |
|-----------|------|
| Pipe A (fills in 6 h) | 120 ÷ 6 = **20 L/h** (in) |
| Pipe B (fills in 2 h) | 120 ÷ 2 = **60 L/h** (in) |
| Drain (empties in 3 h) | 120 ÷ 3 = **40 L/h** (out) |

## Net Inflow

With all three open simultaneously:

$$\text{Net rate} = 20 + 60 - 40 = 40 \text{ L/h}$$

## Time to Fill

$$t = \frac{120 \text{ L}}{40 \text{ L/h}} = 3 \text{ hours}$$

ANSWER: 3

448 tokens: 74 read, 374 written · 15 s · 25.2 tok/s

What does this Python program print? Work it out, then end with a line "ANSWER: <output>".

def f(xs):
    return sorted(xs)[::-1][:2]

print(f([30, 12, 1, 2, 21, 24]))

Let me trace through the program:

1. `f([30, 12, 1, 2, 21, 24])` is called.
2. `sorted(xs)` produces `[1, 2, 12, 21, 24, 30]`
3. `[::-1]` reverses it → `[30, 24, 21, 12, 2, 1]`
4. `[:2]` takes the first two elements → `[30, 24]`
5. The function returns `[30, 24]`, which is printed.

ANSWER: [30, 24]

954 tokens: 93 read, 861 written · 35 s · 25.2 tok/s

What does this Python program print? Work it out, then end with a line "ANSWER: <output>".

def g(n):
    total = 0
    for i in range(1, n + 1):
        if i % 3 == 0 or i % 4 == 0:
            total += i
    return total

print(g(29))

Looking at this program, I need to find the sum of all numbers from 1 to 29 that are divisible by 3 **or** divisible by 4.

**Multiples of 3 (up to 29):** 3, 6, 9, 12, 15, 18, 21, 24, 27
Sum = 3 × (1+2+...+9) = 3 × 45 = **135**

**Multiples of 4 (up to 29):** 4, 8, 12, 16, 20, 24, 28
Sum = 4 × (1+2+...+7) = 4 × 28 = **112**

**Multiples of both 3 and 4 (i.e., multiples of 12, up to 29):** 12, 24
Sum = **36**

By inclusion-exclusion: 135 + 112 − 36 = **211**

ANSWER: 211

514 tokens: 106 read, 408 written · 18 s · 24.2 tok/s

Passes when A final line ANSWER: 6 (it divides by one less than the count).

This function should return the mean of a non-empty list. Which line has the bug? Work it out, then end with a line "ANSWER: <line number>".

1  def average(numbers):
2      """Return the mean of a non-empty list of numbers."""
3      total = 0
4      for n in numbers:
5          total += n
6      count = len(numbers) - 1
7      return total / count

Looking at this function, the goal is to compute the mean (average) of a list, which is:

**mean = sum of elements / number of elements**

Tracing through the logic:

- Lines 3–5 correctly accumulate the sum of all elements into `total`.
- Line 6 sets `count = len(numbers) - 1`. This is the bug. The count should simply be `len(numbers)`. Subtracting 1 means we divide by one fewer element than actually exists, giving an incorrect result.
- Line 7 returns `total / count`, which would be correct if `count` were right.

**Example:** For `[10, 20, 30]`, the correct mean is 60/3 = 20. With the bug, it computes 60/2 = 30.

ANSWER: 6

401 tokens: 144 read, 257 written · 11 s · 25.2 tok/s

What rows does this SQL query return? Output only the rows, one per line, as customer,total in the query's order.

Table orders:
id | customer | amount
1  | ana      | 55
2  | ben      | 105
3  | cal      | 20
4  | ana      | 125
5  | ben      | 20
6  | cal      | 15

Query:
SELECT customer, SUM(amount) AS total
FROM orders
GROUP BY customer
HAVING SUM(amount) > 100
ORDER BY total DESC;

ana,180
ben,125

813 tokens: 707 read, 106 written · 7 s · 24.9 tok/s

Passes when One get_weather call for Lisbon in celsius, then an answer giving the 21 °C the tool returned.

What's the weather in Lisbon right now, in celsius?

1. user

   What's the weather in Lisbon right now, in celsius?

2. assistant

   get_weather({"city":"Lisbon","unit":"celsius"})

3. tool

   {"city": "Lisbon", "conditions": "sunny", "temperature": 21, "unit": "celsius"}

4. assistant

   The current weather in Lisbon is **sunny** with a temperature of **21°C**.

470 tokens: 417 read, 53 written · 4 s · 26 tok/s

Passes when No tool call, and the answer is 144.

What is 12 times 12?

1. user

   What is 12 times 12?

2. assistant

   12 × 12 = **144**

1,044 tokens: 830 read, 214 written · 11 s · 25.6 tok/s

Passes when Converts 250 EUR to USD and to JPY in at most three calls, then gives both amounts: 270.50 USD and 40,125 JPY.

Convert 250 EUR to USD and to JPY.

1. user

   Convert 250 EUR to USD and to JPY.

2. assistant

   convert_currency({"amount":250,"from":"EUR","to":"USD"})

   convert_currency({"amount":250,"from":"EUR","to":"JPY"})

3. tool

   {"amount": 270.5, "currency": "USD"}

4. tool

   {"amount": 40125, "currency": "JPY"}

5. assistant

   Here's the conversion of **250 EUR** at today's rates:
   
   - **250 EUR = 270.50 USD**
   - **250 EUR = 40,125 JPY**

1,551 tokens: 1,311 read, 240 written · 13 s · 25.1 tok/s

Passes when Looks up the customer first, asks for C-1042's orders, then reports A-77 shipped and A-80 processing.

What is the status of each order for the customer with the email kim@example.com?

1. user

   What is the status of each order for the customer with the email kim@example.com?

2. assistant

   I'll start by looking up the customer with that email address.
   
   

   find_customer({"email":"kim@example.com"})

3. tool

   {"customer_id": "C-1042", "name": "Kim Park"}

4. assistant

   I found the customer (Kim Park, C-1042). Now let me retrieve their orders.
   
   

   get_orders({"customer_id":"C-1042"})

5. tool

   {"orders": [{"carrier": "DHL", "order_id": "A-77", "status": "shipped"}, {"order_id": "A-80", "status": "processing"}]}

6. assistant

   Here's the status of each order for **Kim Park** (kim@example.com):
   
   | Order ID | Status | Carrier |
   |----------|------------|---------|
   | A-77 | Shipped | DHL |
   | A-80 | Processing | — |
   
   In summary, one order (A-77) has been shipped via DHL, and the other (A-80) is still being processed.

988 tokens: 745 read, 243 written · 12 s · 24.8 tok/s

Passes when Tries 19:00 for 2 people, never books another time without asking, does not claim the booking succeeded, and offers 18:30 or 20:30.

Book a table for 2 people at Luigi's tonight at 19:00.

1. user

   Book a table for 2 people at Luigi's tonight at 19:00.

2. assistant

   book_table({"restaurant":"Luigi's","people":2,"time":"19:00"})

3. tool

   {"available_times": ["18:30", "20:30"], "error": "fully booked at that time"}

4. assistant

   I'm sorry, but Luigi's is fully booked at 19:00 tonight. However, they do have tables available at:
   
   - **18:30**
   - **20:30**
   
   Would you like me to book one of those times for 2 people instead?

1,625 tokens: 121 read, 1,504 written · 1 min 2 s · 24.6 tok/s

Passes when A <header> with an <h1> naming the bakery, a <nav> with exactly 3 links, a <main> with <section id="menu"> holding at least 4 list items, and a <footer> with opening hours. Nothing loaded from another site and no network requests.

Build a one-page website for a bakery called "Crumb & Co". It must have a <header> containing an <h1> with the bakery's name; a <nav> with exactly 3 links; a <main> with a <section id="menu"> listing at least 4 items in a list; and a <footer> with the opening hours. Output one complete HTML document and nothing else. Put all CSS and JavaScript inline. Do not load anything from another site: no external scripts, stylesheets, fonts or images.

Open the page on its own. It runs in a sandbox: no network, no access to this site.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Crumb &amp; Co — Artisan Bakery</title>
<style>
  * { margin: 0; padding: 0; box-sizing: border-box; }

  body {
    font-family: Georgia, "Times New Roman", serif;
    background: #faf6f0;
    color: #4a3b2f;
    line-height: 1.6;
  }

  header {
    background: #6f4e37;
    color: #fdf6ee;
    text-align: center;
    padding: 2.5rem 1rem 1.5rem;
  }

  header h1 {
    font-size: 2.8rem;
    letter-spacing: 2px;
  }

  header p {
    font-style: italic;
    opacity: 0.9;
    margin-top: 0.4rem;
  }

  nav {
    background: #5a3e2b;
    text-align: center;
    padding: 0.8rem 0;
  }

  nav a {
    color: #fdf6ee;
    text-decoration: none;
    margin: 0 1.2rem;
    font-size: 1.05rem;
    padding-bottom: 2px;
    border-bottom: 2px solid transparent;
    transition: border-color 0.2s ease;
  }

  nav a:hover,
  nav a:focus {
    border-bottom-color: #e8c47c;
  }

  main {
    max-width: 720px;
    margin: 0 auto;
    padding: 2rem 1rem 3rem;
  }

  section#menu {
    background: #ffffff;
    border: 1px solid #e5d9c8;
    border-radius: 10px;
    padding: 2rem;
    box-shadow: 0 3px 10px rgba(0,0,0,0.06);
  }

  section#menu h2 {
    color: #6f4e37;
    border-bottom: 2px solid #e8c47c;
    padding-bottom: 0.5rem;
    margin-bottom: 1rem;
  }

  #menu-list {
    list-style: none;
  }

  #menu-list li {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    padding: 0.7rem 0;
    border-bottom: 1px dotted #d9c9b4;
  }

  #menu-list li:last-child {
    border-bottom: none;
  }

  #menu-list .price {
    color: #8a6d3b;
    font-weight: bold;
    white-space: nowrap;
    margin-left: 1rem;
  }

  .greeting {
    text-align: center;
    margin-top: 1.5rem;
    color: #6f4e37;
    font-style: italic;
  }

  footer {
    background: #6f4e37;
    color: #fdf6ee;
    text-align: center;
    padding: 1.5rem 1rem;
    margin-top: 2rem;
  }

  footer h3 {
    margin-bottom: 0.5rem;
    color: #e8c47c;
  }

  footer ul {
    list-style: none;
  }

  footer li {
    margin: 0.2rem 0;
  }
</style>
</head>
<body>

<header>
  <h1>Crumb &amp; Co</h1>
  <p>Baked fresh every morning</p>
</header>

<nav>
  <a href="#menu">Menu</a>
  <a href="#hours">Hours</a>
  <a href="#top">Home</a>
</nav>

<main id="top">
  <section id="menu">
    <h2>Our Daily Bakes</h2>
    <ul id="menu-list">
      <li><span>Sourdough Loaf</span> <span class="price">$6.50</span></li>
      <li><span>Butter Croissant</span> <span class="price">$3.25</span></li>
      <li><span>Cinnamon Morning Bun</span> <span class="price">$4.00</span></li>
      <li><span>Sugar Glaze Donut</span> <span class="price">$2.75</span></li>
      <li><span>Chocolate Chip Cookie</span> <span class="price">$2.50</span></li>
    </ul>
    <p class="greeting" id="greeting"></p>
  </section>
</main>

<footer id="hours">
  <h3>Opening Hours</h3>
  <ul>
    <li>Monday – Friday: 7:00 AM – 6:00 PM</li>
    <li>Saturday: 8:00 AM – 4:00 PM</li>
    <li>Sunday: 8:00 AM – 2:00 PM</li>
  </ul>
</footer>

<script>
  (function () {
    var hour = new Date().getHours();
    var msg;
    if (hour < 12) {
      msg = "Good morning! Fresh loaves just out of the oven.";
    } else if (hour < 17) {
      msg = "Good afternoon! Croissants are still warm.";
    } else {
      msg = "Good evening! Come see what we baked today.";
    }
    document.getElementById("greeting").textContent = msg;
  })();
</script>

</body>
</html>

2,192 tokens: 92 read, 2,100 written · 1 min 24 s · 25.1 tok/s

Passes when Three elements with class plan, each holding a price, and a <button id="billing-toggle"> handled by script; the page switches between monthly and yearly. Nothing loaded from another site and no network requests.

Build a pricing page with three plans. Each plan is an element with class "plan" containing an element with class "price". Add a <button id="billing-toggle"> that switches every price between monthly and yearly billing when clicked. Output one complete HTML document and nothing else. Put all CSS and JavaScript inline. Do not load anything from another site: no external scripts, stylesheets, fonts or images.

Open the page on its own. It runs in a sandbox: no network, no access to this site.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Pricing</title>
<style>
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }

  body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background: #f4f6fb;
    color: #1f2937;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 60px 20px;
  }

  h1 {
    font-size: 2.5rem;
    margin-bottom: 12px;
    text-align: center;
  }

  .subtitle {
    color: #6b7280;
    margin-bottom: 32px;
    text-align: center;
    font-size: 1.1rem;
  }

  #billing-toggle {
    font-size: 1rem;
    padding: 12px 28px;
    border: none;
    border-radius: 999px;
    background: #4f46e5;
    color: #fff;
    cursor: pointer;
    margin-bottom: 48px;
    transition: background 0.2s ease, transform 0.1s ease;
  }

  #billing-toggle:hover {
    background: #4338ca;
  }

  #billing-toggle:active {
    transform: scale(0.97);
  }

  .plans {
    display: flex;
    gap: 28px;
    flex-wrap: wrap;
    justify-content: center;
    max-width: 1100px;
  }

  .plan {
    background: #ffffff;
    border: 1px solid #e5e7eb;
    border-radius: 16px;
    padding: 36px 28px;
    width: 300px;
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.06);
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
  }

  .plan:hover {
    transform: translateY(-6px);
    box-shadow: 0 10px 24px rgba(0, 0, 0, 0.1);
  }

  .plan.featured {
    border: 2px solid #4f46e5;
    position: relative;
  }

  .plan .badge {
    position: absolute;
    top: -14px;
    background: #4f46e5;
    color: #fff;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    padding: 4px 14px;
    border-radius: 999px;
  }

  .plan h2 {
    font-size: 1.4rem;
    margin-bottom: 8px;
  }

  .plan .description {
    color: #6b7280;
    font-size: 0.95rem;
    margin-bottom: 24px;
    min-height: 44px;
  }

  .plan .price {
    font-size: 2.6rem;
    font-weight: 700;
    color: #111827;
    margin-bottom: 4px;
  }

  .plan .price span.period {
    font-size: 1rem;
    font-weight: 400;
    color: #6b7280;
  }

  .plan ul {
    list-style: none;
    margin: 24px 0 28px;
    text-align: left;
    width: 100%;
  }

  .plan ul li {
    padding: 8px 0;
    font-size: 0.95rem;
    color: #374151;
    border-bottom: 1px solid #f3f4f6;
  }

  .plan ul li:last-child {
    border-bottom: none;
  }

  .plan ul li::before {
    content: "✓";
    color: #4f46e5;
    font-weight: 700;
    margin-right: 10px;
  }

  .plan button.cta {
    margin-top: auto;
    width: 100%;
    padding: 12px;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 10px;
    border: 1px solid #4f46e5;
    background: #fff;
    color: #4f46e5;
    cursor: pointer;
    transition: background 0.2s ease, color 0.2s ease;
  }

  .plan button.cta:hover {
    background: #4f46e5;
    color: #fff;
  }

  .plan.featured button.cta {
    background: #4f46e5;
    color: #fff;
  }

  .plan.featured button.cta:hover {
    background: #4338ca;
  }
</style>
</head>
<body>

  <h1>Simple, transparent pricing</h1>
  <p class="subtitle">Choose the plan that fits your needs.</p>

  <button id="billing-toggle">Switch to yearly billing</button>

  <div class="plans">

    <div class="plan">
      <h2>Starter</h2>
      <p class="description">For individuals just getting started.</p>
      <div class="price" data-monthly="9" data-yearly="90">$9<span class="period">/month</span></div>
      <ul>
        <li>1 project</li>
        <li>5 GB storage</li>
        <li>Community support</li>
      </ul>
      <button class="cta">Get Started</button>
    </div>

    <div class="plan featured">
      <span class="badge">Most Popular</span>
      <h2>Pro</h2>
      <p class="description">For growing teams that need more power.</p>
      <div class="price" data-monthly="29" data-yearly="290">$29<span class="period">/month</span></div>
      <ul>
        <li>Unlimited projects</li>
        <li>100 GB storage</li>
        <li>Priority email support</li>
        <li>Advanced analytics</li>
      </ul>
      <button class="cta">Get Started</button>
    </div>

    <div class="plan">
      <h2>Enterprise</h2>
      <p class="description">For organizations with advanced needs.</p>
      <div class="price" data-monthly="99" data-yearly="990">$99<span class="period">/month</span></div>
      <ul>
        <li>Everything in Pro</li>
        <li>Unlimited storage</li>
        <li>24/7 phone support</li>
        <li>Dedicated account manager</li>
      </ul>
      <button class="cta">Contact Sales</button>
    </div>

  </div>

  <script>
    (function () {
      var toggle = document.getElementById('billing-toggle');
      var prices = document.querySelectorAll('.price');
      var yearly = false;

      function render() {
        prices.forEach(function (price) {
          var value = yearly
            ? price.getAttribute('data-yearly')
            : price.getAttribute('data-monthly');
          var period = yearly ? '/year' : '/month';
          price.innerHTML = '$' + value + '<span class="period">' + period + '</span>';
        });
        toggle.textContent = yearly
          ? 'Switch to monthly billing'
          : 'Switch to yearly billing';
      }

      toggle.addEventListener('click', function () {
        yearly = !yearly;
        render();
      });

      render();
    })();
  </script>

</body>
</html>

1,392 tokens: 127 read, 1,265 written · 52 s · 24.8 tok/s

Passes when <form id="signup"> with name, email (type email) and password (type password, minlength 8 or more) inputs, each with a <label for>; a submit button; an element id="status" with role="status"; and script that stops the submit and writes to the status. Nothing loaded from another site and no network requests.

Build a sign-up form: <form id="signup"> with inputs id="name", id="email" (type email) and id="password" (type password, minlength at least 8), each with a <label for>, and a submit button. When the form is submitted and valid, prevent the real submission and show a confirmation in an element with id="status" and role="status". Output one complete HTML document and nothing else. Put all CSS and JavaScript inline. Do not load anything from another site: no external scripts, stylesheets, fonts or images.

Open the page on its own. It runs in a sandbox: no network, no access to this site.

```html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Sign Up</title>
<style>
  * {
    box-sizing: border-box;
  }

  body {
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background: #f0f2f5;
    margin: 0;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
  }

  form {
    background: #ffffff;
    border-radius: 10px;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
    padding: 2rem;
    width: 100%;
    max-width: 380px;
  }

  h1 {
    font-size: 1.4rem;
    margin: 0 0 1.25rem;
    text-align: center;
    color: #222;
  }

  .field {
    margin-bottom: 1rem;
  }

  label {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 0.35rem;
    color: #333;
  }

  input {
    width: 100%;
    padding: 0.6rem 0.75rem;
    font-size: 1rem;
    border: 1px solid #bbb;
    border-radius: 6px;
    transition: border-color 0.15s, box-shadow 0.15s;
  }

  input:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.2);
  }

  button[type="submit"] {
    width: 100%;
    padding: 0.7rem;
    font-size: 1rem;
    font-weight: 600;
    color: #fff;
    background: #2563eb;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.15s;
    margin-top: 0.5rem;
  }

  button[type="submit"]:hover {
    background: #1d4ed8;
  }

  #status {
    margin-top: 1rem;
    padding: 0.75rem;
    border-radius: 6px;
    font-size: 0.95rem;
    text-align: center;
    display: none;
  }

  #status.success {
    display: block;
    background: #e6f6ea;
    color: #1b6f3a;
    border: 1px solid #b7e0c3;
  }

  .hint {
    font-size: 0.8rem;
    color: #666;
    margin-top: 0.25rem;
  }
</style>
</head>
<body>

<form id="signup" novalidate>
  <h1>Create an account</h1>

  <div class="field">
    <label for="name">Name</label>
    <input type="text" id="name" name="name" required autocomplete="name">
  </div>

  <div class="field">
    <label for="email">Email</label>
    <input type="email" id="email" name="email" required autocomplete="email">
  </div>

  <div class="field">
    <label for="password">Password</label>
    <input type="password" id="password" name="password" minlength="8" required autocomplete="new-password">
    <p class="hint">Must be at least 8 characters long.</p>
  </div>

  <button type="submit">Sign Up</button>

  <div id="status" role="status" aria-live="polite"></div>
</form>

<script>
  (function () {
    var form = document.getElementById("signup");
    var status = document.getElementById("status");
    var name = document.getElementById("name");
    var email = document.getElementById("email");
    var password = document.getElementById("password");

    form.addEventListener("submit", function (event) {
      event.preventDefault();

      // Rely on built-in constraint validation, but force the UI feedback
      if (!form.checkValidity()) {
        status.classList.remove("success");
        status.textContent = "Please fix the highlighted fields and try again.";
        status.classList.add("success");
        // Trigger native validation bubbles
        form.reportValidity();
        return;
      }

      status.textContent = "Thank you, " + name.value.trim() +
        "! Your sign-up was successful.";
      status.classList.add("success");
      form.reset();
    });
  })();
</script>

</body>
</html>
```

1,486 tokens: 115 read, 1,371 written · 55 s · 25.1 tok/s

Passes when The input, add button and list with the given ids, and script that saves to localStorage under "todos" and adds list items with a remove control. Nothing loaded from another site and no network requests.

Build a to-do list app with an <input id="new-task">, a <button id="add"> and a <ul id="tasks">. Clicking add appends the text as an <li> with its own remove button. Save the list in localStorage under the key "todos" and load it again when the page opens. Output one complete HTML document and nothing else. Put all CSS and JavaScript inline. Do not load anything from another site: no external scripts, stylesheets, fonts or images.

Open the page on its own. It runs in a sandbox: no network, no access to this site.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>To-Do List</title>
<style>
  body {
    font-family: system-ui, -apple-system, sans-serif;
    background: #f0f2f5;
    display: flex;
    justify-content: center;
    padding: 40px 16px;
    margin: 0;
  }
  .app {
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.12);
    padding: 24px;
    width: 100%;
    max-width: 420px;
  }
  h1 {
    margin: 0 0 16px;
    font-size: 1.4rem;
    color: #222;
  }
  .input-row {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
  }
  #new-task {
    flex: 1;
    padding: 10px 12px;
    font-size: 1rem;
    border: 1px solid #ccc;
    border-radius: 8px;
    outline-color: #4a90d9;
  }
  #add {
    padding: 10px 18px;
    font-size: 1rem;
    background: #4a90d9;
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
  }
  #add:hover {
    background: #3a7bc0;
  }
  #tasks {
    list-style: none;
    margin: 0;
    padding: 0;
  }
  #tasks li {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    padding: 10px 12px;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    margin-bottom: 8px;
    word-break: break-word;
  }
  #tasks li .remove-btn {
    background: #e74c3c;
    color: #fff;
    border: none;
    border-radius: 6px;
    padding: 4px 10px;
    font-size: 0.85rem;
    cursor: pointer;
    flex-shrink: 0;
  }
  #tasks li .remove-btn:hover {
    background: #c0392b;
  }
  .empty-msg {
    color: #888;
    text-align: center;
    padding: 12px 0;
  }
</style>
</head>
<body>
<div class="app">
  <h1>To-Do List</h1>
  <div class="input-row">
    <input id="new-task" type="text" placeholder="What needs to be done?" autocomplete="off">
    <button id="add" type="button">Add</button>
  </div>
  <ul id="tasks"></ul>
</div>
<script>
(function () {
  var input = document.getElementById('new-task');
  var addButton = document.getElementById('add');
  var list = document.getElementById('tasks');
  var STORAGE_KEY = 'todos';

  var todos = loadTodos();

  function loadTodos() {
    try {
      var raw = localStorage.getItem(STORAGE_KEY);
      var parsed = raw ? JSON.parse(raw) : [];
      return Array.isArray(parsed) ? parsed : [];
    } catch (e) {
      return [];
    }
  }

  function saveTodos() {
    localStorage.setItem(STORAGE_KEY, JSON.stringify(todos));
  }

  function makeLi(text) {
    var li = document.createElement('li');

    var span = document.createElement('span');
    span.textContent = text;

    var removeBtn = document.createElement('button');
    removeBtn.type = 'button';
    removeBtn.className = 'remove-btn';
    removeBtn.textContent = 'Remove';
    removeBtn.setAttribute('aria-label', 'Remove: ' + text);
    removeBtn.addEventListener('click', function () {
      todos = todos.filter(function (t) { return t !== text; });
      saveTodos();
      li.remove();
      maybeShowEmpty();
    });

    li.appendChild(span);
    li.appendChild(removeBtn);
    return li;
  }

  function maybeShowEmpty() {
    if (list.children.length === 0) {
      var li = document.createElement('li');
      var span = document.createElement('span');
      span.className = 'empty-msg';
      span.textContent = 'No tasks yet.';
      li.appendChild(span);
      list.appendChild(li);
    }
  }

  function addTask() {
    var text = input.value.trim();
    if (!text) return;
    todos.push(text);
    saveTodos();
    var emptyMsg = list.querySelector('.empty-msg');
    if (emptyMsg) emptyMsg.parentElement.remove();
    list.appendChild(makeLi(text));
    input.value = '';
    input.focus();
  }

  addButton.addEventListener('click', addTask);
  input.addEventListener('keydown', function (e) {
    if (e.key === 'Enter') addTask();
  });

  todos.forEach(function (text) {
    list.appendChild(makeLi(text));
  });

  if (todos.length === 0) maybeShowEmpty();
})();
</script>
</body>
</html>

1,237 tokens: 140 read, 1,097 written · 45 s · 24.7 tok/s

Passes when Five <rect class="bar"> in an <svg>, written in the markup, with heights proportional to 12, 30, 18, 24 and 6 in that order, labelled Mon to Fri in <text>, and a <title> or aria-label. Nothing loaded from another site and no network requests.

Draw an inline SVG bar chart of coffee sold: Mon 12, Tue 30, Wed 18, Thu 24, Fri 6. Each bar is a <rect class="bar"> whose height attribute is proportional to its value, each bar is labelled with its day in a <text>, and the <svg> has a <title> or an aria-label. Write the bars and labels directly in the SVG markup, not with JavaScript. Output one complete HTML document and nothing else. Put all CSS and JavaScript inline. Do not load anything from another site: no external scripts, stylesheets, fonts or images.

Open the page on its own. It runs in a sandbox: no network, no access to this site.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Coffee Sold This Week</title>
<style>
  body {
    font-family: Arial, Helvetica, sans-serif;
    background: #f5f1ea;
    display: flex;
    justify-content: center;
    padding: 2rem;
  }
  .chart-wrap {
    background: #fff;
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 1rem;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
  }
  h1 {
    font-size: 1.2rem;
    margin: 0 0 0.5rem 0;
    color: #4b2e1a;
  }
  .bar {
    fill: #6f4e37;
    stroke: #4b2e1a;
    stroke-width: 1;
  }
  .bar:hover {
    fill: #8b6544;
  }
  text {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 14px;
    fill: #333;
  }
</style>
</head>
<body>
  <div class="chart-wrap">
    <h1>Coffee Sold This Week</h1>
    <svg xmlns="http://www.w3.org/2000/svg"
         width="420" height="360"
         viewBox="0 0 420 360"
         role="img"
         aria-label="Bar chart of coffee sold: Monday 12, Tuesday 30, Wednesday 18, Thursday 24, Friday 6">
      <title>Coffee sold by day: Mon 12, Tue 30, Wed 18, Thu 24, Fri 6</title>

      <!-- Baseline -->
      <line x1="30" y1="330" x2="400" y2="330" stroke="#999" stroke-width="1"/>

      <!-- Monday: 12 (height 120) -->
      <rect class="bar" x="50" y="210" width="40" height="120"/>
      <text x="70" y="348" text-anchor="middle">Mon</text>
      <text x="70" y="200" text-anchor="middle">12</text>

      <!-- Tuesday: 30 (height 300) -->
      <rect class="bar" x="120" y="30" width="40" height="300"/>
      <text x="140" y="348" text-anchor="middle">Tue</text>
      <text x="140" y="20" text-anchor="middle">30</text>

      <!-- Wednesday: 18 (height 180) -->
      <rect class="bar" x="190" y="150" width="40" height="180"/>
      <text x="210" y="348" text-anchor="middle">Wed</text>
      <text x="210" y="140" text-anchor="middle">18</text>

      <!-- Thursday: 24 (height 240) -->
      <rect class="bar" x="260" y="90" width="40" height="240"/>
      <text x="280" y="348" text-anchor="middle">Thu</text>
      <text x="280" y="80" text-anchor="middle">24</text>

      <!-- Friday: 6 (height 60) -->
      <rect class="bar" x="330" y="270" width="40" height="60"/>
      <text x="350" y="348" text-anchor="middle">Fri</text>
      <text x="350" y="260" text-anchor="middle">6</text>
    </svg>
  </div>
</body>
</html>

3,362 tokens: 461 read, 2,901 written · 2 min 1 s · 24.4 tok/s

Build the game 2048 as one web page, playable with the arrow keys, with the board drawn on the page.

In <script id="game">, define createGame() returning an object with move(dir) and state(). dir is "up", "down", "left" or "right". state() returns {board, score, over}: board is 4 rows of 4 numbers, top row first (0 is an empty cell), score is a number, over is a boolean.

The rules, exactly:
1. The board starts as this one, then a 2 is put in each of the first two empty cells in reading order (row by row from the top, left to right). The score starts at 0.
[16, 16, 0, 16]
[0, 0, 4, 32]
[0, 0, 0, 0]
[2, 0, 0, 0]
2. A move slides every tile as far as it goes toward dir. Two tiles of the same value that meet merge into one tile of their sum, nearest the side they move toward first: moving left, [2,2,2,2] becomes [4,4,0,0] and [2,2,2,0] becomes [4,2,0,0]. A tile made by a merge does not merge again in the same move.
3. Each merge adds the new tile's value to the score.
4. If a move changed the board, a 2 is put in the first empty cell in reading order. A move that changes nothing does nothing.
5. over is true when no move would change the board; then moves do nothing.

Output one complete HTML document and nothing else, with all CSS and JavaScript inline and nothing loaded from another site. Put the game logic, and only it, in <script id="game">: it must not touch document, window or timers, because the site runs that script on its own and plays the game through createGame(). Wire the page in another <script>.

Open the page on its own. It runs in a sandbox: no network, no access to this site.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>2048</title>
<style>
  body {
    margin: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: #faf8ef;
    font-family: "Helvetica Neue", Arial, sans-serif;
  }
  h1 { margin: 0 0 10px; color: #776e65; font-size: 40px; }
  #hud {
    display: flex;
    gap: 10px;
    align-items: center;
    margin-bottom: 14px;
  }
  #score {
    background: #bbada0;
    color: #fff;
    padding: 8px 18px;
    border-radius: 6px;
    font-size: 20px;
    font-weight: bold;
  }
  #board {
    position: relative;
    background: #bbada0;
    border-radius: 8px;
    padding: 10px;
    display: grid;
    grid-template-columns: repeat(4, 90px);
    grid-template-rows: repeat(4, 90px);
    gap: 10px;
  }
  .cell {
    background: rgba(238, 228, 218, 0.35);
    border-radius: 6px;
  }
  .tile {
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 34px;
    font-weight: bold;
    color: #776e65;
  }
  .tile.empty { background: rgba(238, 228, 218, 0.35); color: transparent; }
  .v2    { background: #eee4da; color: #776e65; }
  .v4    { background: #ede0c8; color: #776e65; }
  .v8    { background: #f2b179; color: #f9f6f2; }
  .v16   { background: #f59563; color: #f9f6f2; }
  .v32   { background: #f67c5f; color: #f9f6f2; }
  .v64   { background: #f65e3b; color: #f9f6f2; }
  .v128  { background: #edcf72; color: #f9f6f2; font-size: 28px; }
  .v256  { background: #edcc61; color: #f9f6f2; font-size: 28px; }
  .v512  { background: #edc850; color: #f9f6f2; font-size: 28px; }
  .v1024 { background: #edc53f; color: #f9f6f2; font-size: 22px; }
  .v2048 { background: #edc22e; color: #f9f6f2; font-size: 22px; }
  .bigger { background: #3c3a32; color: #f9f6f2; font-size: 22px; }
  #hint { margin-top: 14px; color: #776e65; }
  #gameover {
    position: absolute;
    inset: 0;
    background: rgba(238, 228, 218, 0.73);
    border-radius: 8px;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 48px;
    font-weight: bold;
    color: #776e65;
  }
  #gameover.show { display: flex; }
</style>
</head>
<body>
<h1>2048</h1>
<div id="hud">
  <div id="score">0</div>
</div>
<div id="board">
  <div id="gameover">Game Over</div>
</div>
<div id="hint">Use the arrow keys to play</div>

<script id="game">
function createGame() {
  var start = [
    [16, 16, 0, 16],
    [0, 0, 4, 32],
    [0, 0, 0, 0],
    [2, 0, 0, 0]
  ];
  var board = start.map(function (r) { return r.slice(); });
  var score = 0;
  var over = false;

  function firstEmpty() {
    for (var r = 0; r < 4; r++) {
      for (var c = 0; c < 4; c++) {
        if (board[r][c] === 0) return { r: r, c: c };
      }
    }
    return null;
  }

  // Rule 1: initial spawn of two 2s in first empty cells, reading order.
  for (var i = 0; i < 2; i++) {
    var p = firstEmpty();
    if (p) board[p.r][p.c] = 2;
  }

  // Slide one row to the left, merging equal neighbours once each.
  // Returns {row, gained, changed}.
  function slideRow(row) {
    var vals = row.filter(function (v) { return v !== 0; });
    var out = [];
    var gained = 0;
    var i = 0;
    while (i < vals.length) {
      if (i + 1 < vals.length && vals[i] === vals[i + 1]) {
        var merged = vals[i] * 2;
        out.push(merged);
        gained += merged;
        i += 2;
      } else {
        out.push(vals[i]);
        i += 1;
      }
    }
    while (out.length < 4) out.push(0);
    var changed = false;
    for (var j = 0; j < 4; j++) {
      if (out[j] !== row[j]) { changed = true; break; }
    }
    return { row: out, gained: gained, changed: changed };
  }

  // Extract a line of 4 cells toward the move direction.
  function line(dir, idx) {
    var res = [];
    for (var k = 0; k < 4; k++) {
      if (dir === "left")  res.push(board[idx][k]);
      if (dir === "right") res.push(board[idx][3 - k]);
      if (dir === "up")    res.push(board[k][idx]);
      if (dir === "down")  res.push(board[3 - k][idx]);
    }
    return res;
  }

  // Write a slid line back toward the move direction.
  function putLine(dir, idx, cells) {
    for (var k = 0; k < 4; k++) {
      if (dir === "left")  board[idx][k] = cells[k];
      if (dir === "right") board[idx][3 - k] = cells[k];
      if (dir === "up")    board[k][idx] = cells[k];
      if (dir === "down")  board[3 - k][idx] = cells[k];
    }
  }

  function canMove() {
    if (firstEmpty()) return true;
    for (var r = 0; r < 4; r++) {
      for (var c = 0; c < 4; c++) {
        if (c < 3 && board[r][c] === board[r][c + 1]) return true;
        if (r < 3 && board[r][c] === board[r + 1][c]) return true;
      }
    }
    return false;
  }

  function applyMove(dir) {
    var gained = 0;
    var changed = false;
    for (var idx = 0; idx < 4; idx++) {
      var before = line(dir, idx);
      var res = slideRow(before);
      putLine(dir, idx, res.row);
      gained += res.gained;
      if (res.changed) changed = true;
    }
    if (changed) {
      score += gained;
      var p = firstEmpty();
      if (p) board[p.r][p.c] = 2;
      over = !canMove();
    }
  }

  return {
    move: function (dir) {
      if (over) return;
      if (dir !== "up" && dir !== "down" && dir !== "left" && dir !== "right") return;
      applyMove(dir);
    },
    state: function () {
      return {
        board: board.map(function (r) { return r.slice(); }),
        score: score,
        over: over
      };
    }
  };
}
</script>

<script>
(function () {
  var game = createGame();
  var boardEl = document.getElementById("board");
  var scoreEl = document.getElementById("score");
  var overEl = document.getElementById("gameover");

  function tileClass(v) {
    if (v === 0) return "tile empty";
    if (v <= 2048) return "tile v" + v;
    return "tile bigger";
  }

  function render() {
    var st = game.state();
    // Remove previous cells (keep the overlay)
    var children = Array.prototype.slice.call(boardEl.children);
    children.forEach(function (el) {
      if (el !== overEl) el.parentNode.removeChild(el);
    });
    for (var r = 0; r < 4; r++) {
      for (var c = 0; c < 4; c++) {
        var d = document.createElement("div");
        d.className = tileClass(st.board[r][c]);
        d.textContent = st.board[r][c] === 0 ? "" : st.board[r][c];
        boardEl.appendChild(d);
      }
    }
    scoreEl.textContent = st.score;
    overEl.classList.toggle("show", st.over);
  }

  var keys = {
    ArrowUp: "up",
    ArrowDown: "down",
    ArrowLeft: "left",
    ArrowRight: "right"
  };

  document.addEventListener("keydown", function (e) {
    var dir = keys[e.key];
    if (!dir) return;
    e.preventDefault();
    game.move(dir);
    render();
  });

  render();
})();
</script>
</body>
</html>

3,271 tokens: 455 read, 2,816 written · 2 min 1 s · 23.7 tok/s

Build Snake as one web page on a 10 by 10 grid, playable with the arrow keys (one key press, one step), with the grid drawn on the page.

In <script id="game">, define createGame() returning an object with step(dir) and state(). dir is "up", "down", "left" or "right". state() returns {snake, food, score, over}: snake is a list of [x, y] cells, head first; food is [x, y]; score is a number; over is a boolean. x is the column (0 to 9, left to right), y the row (0 to 9, top to bottom); up is y - 1.

The rules, exactly:
1. The game starts with snake [[6, 3], [7, 3], [8, 3]], moving left, food at [1, 5], score 0.
2. step(dir): if dir is the opposite of the current direction it is ignored and the snake keeps going; otherwise dir becomes the current direction. The head moves one cell that way.
3. If the new head cell holds the food, the snake grows: its tail stays. Otherwise the tail cell is freed first.
4. If the new head is off the grid or on a cell of the snake (after rule 3), the game is over: over becomes true and nothing else changes. Once over, step does nothing.
5. Eating adds 1 to the score, and the next food goes to the first empty cell in reading order (row by row from the top, left to right) after the new head's cell, wrapping from [9, 9] to [0, 0].

Output one complete HTML document and nothing else, with all CSS and JavaScript inline and nothing loaded from another site. Put the game logic, and only it, in <script id="game">: it must not touch document, window or timers, because the site runs that script on its own and plays the game through createGame(). Wire the page in another <script>.

Open the page on its own. It runs in a sandbox: no network, no access to this site.

```html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Snake</title>
<style>
  body {
    font-family: sans-serif;
    background: #1e1e28;
    color: #eee;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px;
  }
  h1 { margin: 0 0 10px; font-weight: 600; }
  #hud {
    display: flex;
    gap: 24px;
    margin-bottom: 10px;
    font-size: 18px;
  }
  #board-wrap { position: relative; }
  canvas {
    display: block;
    background: #2b2b3a;
    border: 2px solid #555;
    border-radius: 4px;
  }
  #overlay {
    position: absolute;
    inset: 0;
    display: none;
    align-items: center;
    justify-content: center;
    background: rgba(0, 0, 0, 0.6);
    color: #ff5555;
    font-size: 32px;
    font-weight: bold;
    border-radius: 4px;
  }
  #hint { margin-top: 10px; font-size: 14px; color: #999; }
</style>
</head>
<body>
  <h1>Snake</h1>
  <div id="hud">
    <span>Score: <span id="score">0</span></span>
  </div>
  <div id="board-wrap">
    <canvas id="board" width="320" height="320"></canvas>
    <div id="overlay">Game Over</div>
  </div>
  <div id="hint">Use the arrow keys. One key press moves the snake one step.</div>

<script id="game">
function createGame() {
  var SIZE = 10;
  var opposite = { up: "down", down: "up", left: "right", right: "left" };

  var snake = [[6, 3], [7, 3], [8, 3]];
  var food = [1, 5];
  var score = 0;
  var over = false;
  var dir = "left";

  function placeFood(afterHead) {
    var start = afterHead[1] * SIZE + afterHead[0] + 1;
    for (var i = 0; i < SIZE * SIZE; i++) {
      var j = (start + i) % (SIZE * SIZE);
      var x = j % SIZE;
      var y = Math.floor(j / SIZE);
      var taken = false;
      for (var k = 0; k < snake.length; k++) {
        if (snake[k][0] === x && snake[k][1] === y) { taken = true; break; }
      }
      if (!taken) { food = [x, y]; return; }
    }
    // No empty cell left (grid full): leave food where it is.
  }

  function step(newDir) {
    if (over) return;
    if (newDir !== opposite[dir]) dir = newDir;

    var head = snake[0];
    var nx = head[0], ny = head[1];
    if (dir === "left") nx--;
    else if (dir === "right") nx++;
    else if (dir === "up") ny--;
    else if (dir === "down") ny++;

    if (nx < 0 || nx >= SIZE || ny < 0 || ny >= SIZE) {
      over = true;
      return;
    }

    var eating = (nx === food[0] && ny === food[1]);
    if (!eating) {
      snake.pop(); // free the tail before checking collisions
    }

    for (var i = 0; i < snake.length; i++) {
      if (snake[i][0] === nx && snake[i][1] === ny) {
        over = true;
        return;
      }
    }

    snake.unshift([nx, ny]);

    if (eating) {
      score++;
      placeFood([nx, ny]);
    }
  }

  function state() {
    return {
      snake: snake.map(function (c) { return [c[0], c[1]]; }),
      food: [food[0], food[1]],
      score: score,
      over: over
    };
  }

  return { step: step, state: state };
}
</script>

<script>
(function () {
  var game = createGame();

  var canvas = document.getElementById("board");
  var ctx = canvas.getContext("2d");
  var scoreEl = document.getElementById("score");
  var overlay = document.getElementById("overlay");
  var CELL = 32;

  function draw() {
    var s = game.state();

    ctx.clearRect(0, 0, canvas.width, canvas.height);

    // grid lines
    ctx.strokeStyle = "#3d3d50";
    ctx.lineWidth = 1;
    for (var i = 1; i < 10; i++) {
      ctx.beginPath();
      ctx.moveTo(i * CELL + 0.5, 0);
      ctx.lineTo(i * CELL + 0.5, canvas.height);
      ctx.stroke();
      ctx.beginPath();
      ctx.moveTo(0, i * CELL + 0.5);
      ctx.lineTo(canvas.width, i * CELL + 0.5);
      ctx.stroke();
    }

    // food
    ctx.fillStyle = "#ff5555";
    ctx.fillRect(s.food[0] * CELL + 4, s.food[1] * CELL + 4, CELL - 8, CELL - 8);

    // snake
    for (var i = s.snake.length - 1; i >= 0; i--) {
      ctx.fillStyle = (i === 0) ? "#7cff8e" : "#4db861";
      ctx.fillRect(s.snake[i][0] * CELL + 2, s.snake[i][1] * CELL + 2, CELL - 4, CELL - 4);
    }

    scoreEl.textContent = s.score;
    overlay.style.display = s.over ? "flex" : "none";
  }

  var keys = {
    ArrowUp: "up",
    ArrowDown: "down",
    ArrowLeft: "left",
    ArrowRight: "right"
  };

  document.addEventListener("keydown", function (e) {
    var dir = keys[e.key];
    if (!dir) return;
    e.preventDefault();
    game.step(dir);
    draw();
  });

  draw();
})();
</script>
</body>
</html>
```

662 tokens: 158 read, 504 written · 22 s · 24.2 tok/s

Write a JavaScript function mergeIntervals(intervals). intervals is an array of [start, end] pairs of integers with start <= end, in any order, possibly empty. Return a new array of the merged intervals sorted by start: intervals that overlap or touch (one ends where the next starts) become one. Do not change the input array or its pairs.

mergeIntervals([[8, 10], [1, 3], [2, 6], [6, 7]]) returns [[1, 7], [8, 10]].

Reply with one ```js code block holding plain JavaScript (no imports, no exports, no DOM, no timers). The site runs it with hidden tests.

```js
function mergeIntervals(intervals) {
  if (!intervals || intervals.length === 0) return [];

  // Work on a deep copy of the pairs so the input stays untouched
  const sorted = intervals
    .map((pair) => [pair[0], pair[1]])
    .sort((a, b) => (a[0] - b[0]) || (a[1] - b[1]));

  const merged = [sorted[0].slice()];

  for (let i = 1; i < sorted.length; i++) {
    const current = sorted[i];
    const last = merged[merged.length - 1];

    // Overlap or touch (current.start <= last.end)
    if (current[0] <= last[1]) {
      if (current[1] > last[1]) {
        last[1] = current[1];
      }
    } else {
      merged.push([current[0], current[1]]);
    }
  }

  return merged;
}
```

489 tokens: 168 read, 321 written · 15 s · 23 tok/s

Write a JavaScript class LRUCache: a least-recently-used cache of integer keys and values.

- new LRUCache(capacity): capacity is an integer of at least 1.
- get(key) returns the value stored for key, or -1 if there is none. A get that finds the key makes it the most recently used.
- put(key, value) stores the value (replacing any value already there) and makes key the most recently used. If that leaves more than capacity keys, the least recently used key is removed.

get and put should take constant time on average.

Reply with one ```js code block holding plain JavaScript (no imports, no exports, no DOM, no timers). The site runs it with hidden tests.

```js
class LRUCache {
  constructor(capacity) {
    this.capacity = capacity;
    this.map = new Map();
  }

  get(key) {
    if (!this.map.has(key)) return -1;
    const value = this.map.get(key);
    // refresh recency: move key to the end (most recently used)
    this.map.delete(key);
    this.map.set(key, value);
    return value;
  }

  put(key, value) {
    if (this.map.has(key)) {
      // refresh recency
      this.map.delete(key);
    } else {
      if (this.map.size >= this.capacity) {
        // evict least recently used (first inserted key)
        const lruKey = this.map.keys().next().value;
        this.map.delete(lruKey);
      }
    }
    this.map.set(key, value);
  }
}
```

2,693 tokens: 194 read, 2,499 written · 1 min 47 s · 23.7 tok/s

Write a JavaScript function evaluate(expr) that returns the value of an arithmetic expression given as a string. The expression has non-negative integers, the operators + - * /, parentheses, unary minus (as in -3, - -3, 2 * -3 or -(1 + 2)) and spaces anywhere between tokens. * and / bind tighter than + and -, and operators of the same kind group from the left. / is integer division that truncates toward zero: 7 / 2 is 3 and -7 / 2 is -3. Dividing by zero must throw an Error. Do not use eval or Function.

evaluate("2 + 3 * (4 - 6) / 4") returns 1.

Reply with one ```js code block holding plain JavaScript (no imports, no exports, no DOM, no timers). The site runs it with hidden tests.

```js
function evaluate(expr) {
    let pos = 0;

    function skipSpaces() {
        while (pos < expr.length && expr[pos] === ' ') pos++;
    }

    function parseExpression() {
        let result = parseTerm();
        for (;;) {
            skipSpaces();
            if (pos < expr.length && (expr[pos] === '+' || expr[pos] === '-')) {
                let op = expr[pos];
                pos++;
                let right = parseTerm();
                if (op === '+') result += right;
                else result -= right;
            } else break;
        }
        return result;
    }

    function parseTerm() {
        let result = parseFactor();
        for (;;) {
            skipSpaces();
            if (pos < expr.length && (expr[pos] === '*' || expr[pos] === '/')) {
                let op = expr[pos];
                pos++;
                let right = parseFactor();
                if (op === '*') result *= right;
                else {
                    if (right === 0) throw new Error("Division by zero");
                    result = Math.trunc(result / right);
                }
            } else break;
        }
        return result;
    }

    function parseFactor() {
        skipSpaces();
        if (pos < expr.length && expr[pos] === '-') {
            pos++;
            return -parseFactor();
        }
        return parsePrimary();
    }

    function parsePrimary() {
        skipSpaces();
        if (pos < expr.length && expr[pos] === '(') {
            pos++;
            let result = parseExpression();
            skipSpaces();
            if (pos >= expr.length || expr[pos] !== ')') throw new Error("Expected )");
            pos++;
            return result;
        }
        let start = pos;
        while (pos < expr.length && expr[pos] >= '0' && expr[pos] <= '9') pos++;
        if (pos === start) throw new Error("Expected number");
        return parseInt(expr.substring(start, pos), 10);
    }

    let result = parseExpression();
    skipSpaces();
    return result;
}
```

1,808 tokens: 669 read, 1,139 written · 50 s · 24.2 tok/s

This JavaScript module has one bug. The occupancy report sometimes counts one booked night more than there is in the range it was asked about.

Find it and fix it without changing anything else.

```js
// Bookings for one holiday flat. A booking is { guest, checkIn, checkOut } with dates as "YYYY-MM-DD".
// A guest sleeps the nights from checkIn up to, but not including, checkOut: checkOut is the day they leave,
// and another guest may check in that same day.

function dayNumber(date) {
  const [y, m, d] = date.split('-').map(Number);
  return Date.UTC(y, m - 1, d) / 86400000;
}

function toDate(day) {
  return new Date(day * 86400000).toISOString().slice(0, 10);
}

function nights(booking) {
  return dayNumber(booking.checkOut) - dayNumber(booking.checkIn);
}

function overlaps(a, b) {
  return dayNumber(a.checkIn) < dayNumber(b.checkOut) && dayNumber(b.checkIn) < dayNumber(a.checkOut);
}

function canBook(bookings, request) {
  if (nights(request) < 1) return false;
  for (const booking of bookings) {
    if (overlaps(booking, request)) return false;
  }
  return true;
}

function isBooked(bookings, day) {
  return bookings.some((b) => dayNumber(b.checkIn) <= day && day < dayNumber(b.checkOut));
}

// The nights from `from` up to, but not including, `to` that someone has booked.
function bookedNights(bookings, from, to) {
  let count = 0;
  for (let day = dayNumber(from); day <= dayNumber(to); day++) {
    if (isBooked(bookings, day)) count++;
  }
  return count;
}

// The first night on or after `from` that nobody has booked, as "YYYY-MM-DD".
function firstFreeNight(bookings, from) {
  let day = dayNumber(from);
  while (isBooked(bookings, day)) day++;
  return toDate(day);
}

// The price in cents: Friday and Saturday nights at rates.weekend, every other night at rates.weekday.
function price(booking, rates) {
  let total = 0;
  for (let day = dayNumber(booking.checkIn); day < dayNumber(booking.checkOut); day++) {
    const weekday = new Date(day * 86400000).getUTCDay();
    total += weekday === 5 || weekday === 6 ? rates.weekend : rates.weekday;
  }
  return total;
}
```

Reply with the whole corrected module in one ```js code block, with the same function names.

```js
// Bookings for one holiday flat. A booking is { guest, checkIn, checkOut } with dates as "YYYY-MM-DD".
// A guest sleeps the nights from checkIn up to, but not including, checkOut: checkOut is the day they leave,
// and another guest may check in that same day.

function dayNumber(date) {
  const [y, m, d] = date.split('-').map(Number);
  return Date.UTC(y, m - 1, d) / 86400000;
}

function toDate(day) {
  return new Date(day * 86400000).toISOString().slice(0, 10);
}

function nights(booking) {
  return dayNumber(booking.checkOut) - dayNumber(booking.checkIn);
}

function overlaps(a, b) {
  return dayNumber(a.checkIn) < dayNumber(b.checkOut) && dayNumber(b.checkIn) < dayNumber(a.checkOut);
}

function canBook(bookings, request) {
  if (nights(request) < 1) return false;
  for (const booking of bookings) {
    if (overlaps(booking, request)) return false;
  }
  return true;
}

function isBooked(bookings, day) {
  return bookings.some((b) => dayNumber(b.checkIn) <= day && day < dayNumber(b.checkOut));
}

// The nights from `from` up to, but not including, `to` that someone has booked.
function bookedNights(bookings, from, to) {
  let count = 0;
  for (let day = dayNumber(from); day < dayNumber(to); day++) {
    if (isBooked(bookings, day)) count++;
  }
  return count;
}

// The first night on or after `from` that nobody has booked, as "YYYY-MM-DD".
function firstFreeNight(bookings, from) {
  let day = dayNumber(from);
  while (isBooked(bookings, day)) day++;
  return toDate(day);
}

// The price in cents: Friday and Saturday nights at rates.weekend, every other night at rates.weekday.
function price(booking, rates) {
  let total = 0;
  for (let day = dayNumber(booking.checkIn); day < dayNumber(booking.checkOut); day++) {
    const weekday = new Date(day * 86400000).getUTCDay();
    total += weekday === 5 || weekday === 6 ? rates.weekend : rates.weekday;
  }
  return total;
}
```

The bug was in `bookedNights`: the loop condition used `day <= dayNumber(to)`, which included the `to` day. Since the function's contract is "nights from `from` up to, but **not including**, `to`", the upper bound must be exclusive. Changing `<=` to `<` fixes the off-by-one that caused an extra booked night to be counted when the `to` date itself happened to be an occupied night.

1,728 tokens: 514 read, 1,214 written · 53 s · 24.1 tok/s

This JavaScript module has one bug. A quoted field with a comma in it, such as "Smith, Jane", is split in two.

Find it and fix it without changing anything else.

```js
// Reads CSV the way spreadsheets write it: fields are separated by commas, a field may be wrapped in
// double quotes so it can hold commas, and "" inside a quoted field stands for one double quote.
// Fields are not trimmed. Empty lines are skipped.

function parseLine(line) {
  const fields = [];
  let field = '';
  let quoted = false;
  for (let i = 0; i < line.length; i++) {
    const ch = line[i];
    if (quoted && ch !== ',') {
      if (ch === '"') {
        if (line[i + 1] === '"') {
          field += '"';
          i++;
        } else {
          quoted = false;
        }
      } else {
        field += ch;
      }
    } else if (ch === '"') {
      quoted = true;
    } else if (ch === ',') {
      fields.push(field);
      field = '';
    } else {
      field += ch;
    }
  }
  fields.push(field);
  return fields;
}

function parseCSV(text) {
  return text.split(/\r?\n/).filter((line) => line !== '').map(parseLine);
}

// Each row after the header as an object keyed by the header's names; a missing field is ''.
function toObjects(text) {
  const [header, ...rows] = parseCSV(text);
  return rows.map((row) => {
    const record = {};
    header.forEach((name, i) => {
      record[name] = i < row.length ? row[i] : '';
    });
    return record;
  });
}

// The sum of a column's numbers; fields that are not numbers count as 0.
function sumColumn(text, name) {
  return toObjects(text).reduce((total, record) => total + (Number(record[name]) || 0), 0);
}
```

Reply with the whole corrected module in one ```js code block, with the same function names.

The bug is in `parseLine`: the first branch condition is `quoted && ch !== ','`, so when a comma appears *inside* a quoted field, that branch is skipped and execution falls through to the `ch === ','` separator branch, incorrectly splitting the field.

The fix is to remove the `ch !== ','` guard so that commas inside a quoted field are simply appended like any other character.

```js
// Reads CSV the way spreadsheets write it: fields are separated by commas, a field may be wrapped in
// double quotes so it can hold commas, and "" inside a quoted field stands for one double quote.
// Fields are not trimmed. Empty lines are skipped.

function parseLine(line) {
  const fields = [];
  let field = '';
  let quoted = false;
  for (let i = 0; i < line.length; i++) {
    const ch = line[i];
    if (quoted) {
      if (ch === '"') {
        if (line[i + 1] === '"') {
          field += '"';
          i++;
        } else {
          quoted = false;
        }
      } else {
        field += ch;
      }
    } else if (ch === '"') {
      quoted = true;
    } else if (ch === ',') {
      fields.push(field);
      field = '';
    } else {
      field += ch;
    }
  }
  fields.push(field);
  return fields;
}

function parseCSV(text) {
  return text.split(/\r?\n/).filter((line) => line !== '').map(parseLine);
}

// Each row after the header as an object keyed by the header's names; a missing field is ''.
function toObjects(text) {
  const [header, ...rows] = parseCSV(text);
  return rows.map((row) => {
    const record = {};
    header.forEach((name, i) => {
      record[name] = i < row.length ? row[i] : '';
    });
    return record;
  });
}

// The sum of a column's numbers; fields that are not numbers count as 0.
function sumColumn(text, name) {
  return toObjects(text).reduce((total, record) => total + (Number(record[name]) || 0), 0);
}
```

621 tokens: 216 read, 405 written · 18 s · 23.7 tok/s

Write one SQLite query that answers the question below. The site runs it on its own copy of these tables, filled with rows you have not seen.

```sql
CREATE TABLE customers (id INTEGER PRIMARY KEY, name TEXT NOT NULL, city TEXT NOT NULL);
CREATE TABLE orders (id INTEGER PRIMARY KEY, customer_id INTEGER NOT NULL REFERENCES customers(id),
                     placed TEXT NOT NULL,  -- 'YYYY-MM-DD'
                     status TEXT NOT NULL); -- 'delivered', 'cancelled' or 'pending'
CREATE TABLE items (order_id INTEGER NOT NULL REFERENCES orders(id), product TEXT NOT NULL,
                    quantity INTEGER NOT NULL, price_cents INTEGER NOT NULL);  -- price_cents: for one unit
```

Question: The names of the customers with at least 2 delivered orders and no cancelled order. One column: name. In alphabetical order.

Reply with only the query, in one ```sql code block: one SELECT statement (WITH is fine), nothing that changes the database.

```sql
SELECT c.name
FROM customers c
JOIN orders o ON o.customer_id = c.id
GROUP BY c.id
HAVING SUM(CASE WHEN o.status = 'delivered' THEN 1 ELSE 0 END) >= 2
   AND SUM(CASE WHEN o.status = 'cancelled' THEN 1 ELSE 0 END) = 0
ORDER BY c.name;
```

3,709 tokens: 290 read, 3,419 written · 2 min 26 s · 23.6 tok/s

Five people each have one meeting today: Dev, Eli, Hal, Kim, Noa. The five meetings are at different times, 09:00, 10:00, 11:00, 13:00, 14:00 (in that order: 10:00 is right after 09:00, 13:00 right after 11:00), and in different rooms. The list of rooms, in order: Cedar, Maple, Oak, Rowan, Willow.

1. Whoever is in Willow meets earlier than Noa.
2. Dev is not in Maple.
3. Dev meets earlier than Hal.
4. Eli is not in Maple.
5. Hal meets earlier than Eli.
6. Eli's and Noa's rooms are next to each other on the list of rooms.
7. Dev is not in Willow.
8. Whoever is in Maple meets earlier than Kim.
9. Hal's and Noa's rooms are next to each other on the list of rooms.
10. Kim meets after lunch.

Exactly one schedule fits every clue. Work it out, then end with exactly five lines, one per person, in this form:
Ana: 09:00, Oak

# Working Through the Schedule

## Key Constraints

From clues 3 & 5: **Dev < Hal < Eli** (time order)
From clue 10: **Kim at 13:00 or 14:00**

## Placing Noa's Room

Clues 6 & 9 require Noa's room to be adjacent to **both** Eli's and Hal's rooms. In a 5-room list, only positions 2 (Maple), 3 (Oak), or 4 (Rowan) have two neighbors. So Noa ∈ {Maple, Oak, Rowan}.

## Eliminating Cases

- **Noa in Maple:** Eli/Hal take Cedar & Oak; Dev must take Rowan (not Maple, not Willow); Kim takes Willow. But then clue 1 forces Kim (Willow) < Noa, and clue 8 forces Noa (Maple) < Kim — a contradiction. ❌
- **Noa in Rowan:** Eli/Hal take Oak & Willow; Dev must take Cedar (not Maple, not Willow); Kim takes Maple. But clue 8 says "Maple meets earlier than Kim," and Kim *is* Maple — impossible. ❌
- **Noa in Oak:** Eli/Hal take Maple & Rowan. Clue 4 (Eli ≠ Maple) forces **Hal → Maple, Eli → Rowan**. Dev → Cedar, Kim → Willow. ✅

## Assigning Times

- Clue 1: Kim (Willow) < Noa → Kim 13:00, Noa 14:00.
- Remaining slots (09, 10, 11) for Dev, Hal, Eli with Dev < Hal < Eli → **Dev 09:00, Hal 10:00, Eli 11:00**.

## Verification

| Clue | Check |
|------|-------|
| 1. Willow (13:00) < Noa (14:00) | ✓ |
| 2. Dev ≠ Maple (Cedar) | ✓ |
| 3. Dev (09) < Hal (10) | ✓ |
| 4. Eli ≠ Maple (Rowan) | ✓ |
| 5. Hal (10) < Eli (11) | ✓ |
| 6. Eli (Rowan) adj. Noa (Oak) | ✓ |
| 7. Dev ≠ Willow (Cedar) | ✓ |
| 8. Maple/Hal (10) < Kim (13) | ✓ |
| 9. Hal (Maple) adj. Noa (Oak) | ✓ |
| 10. Kim at 13:00 (after lunch) | ✓ |

## Solution

Dev: 09:00, Cedar
Eli: 11:00, Rowan
Hal: 10:00, Maple
Kim: 13:00, Willow
Noa: 14:00, Oak

11,512 tokens: 10,600 read, 912 written · 49 s · 23.9 tok/s

Passes when Looks up the account, opens order R-5530 (the kettle), checks north then south and stops, reserves one steel kettle at south for R-5530, opens a damage claim (a return, if tried, is refused), makes at most 10 calls, and tells the customer claim CL-2207 and that the replacement ships on 3 November, without claiming a return label.

Hi, it's ana.silva@example.com. My kettle arrived with a cracked lid. Can you sort it out?

1. system

   You are the support agent of Tidewell Home, working through its tools. When an item arrives damaged: confirm which order it came in, send a replacement from the north warehouse if it has the item, else from south, else from east (check each in that order, and only as far as needed), and take the damaged item back with a return. Then reply to the customer with what you did, giving any reference numbers and the date the replacement ships.

2. user

   Hi, it's ana.silva@example.com. My kettle arrived with a cracked lid. Can you sort it out?

3. assistant

   I'll sort this out for you. Let me look up your account first.
   
   

   lookup_account({"email":"ana.silva@example.com"})

4. tool

   {"account_id": "AC-311", "name": "Ana Silva"}

5. assistant

   Thanks, Ana. Let me find the order that included your kettle.
   
   

   list_orders({"account_id":"AC-311"})

6. tool

   {"orders": [{"order_id": "R-5521", "placed": "2026-10-02", "status": "delivered"}, {"order_id": "R-5530", "placed": "2026-10-09", "status": "delivered"}, {"order_id": "R-5544", "placed": "2026-10-20", "status": "in transit"}]}

7. assistant

   Let me check your delivered orders to find the kettle.
   
   

   get_order({"order_id":"R-5521"})

   get_order({"order_id":"R-5530"})

8. tool

   {"items": [{"name": "Oak table lamp", "quantity": 1, "sku": "lamp-oak"}], "order_id": "R-5521"}

9. tool

   {"items": [{"name": "Steel kettle", "quantity": 1, "sku": "kettle-steel"}, {"name": "Grey mug", "quantity": 2, "sku": "mug-grey"}], "order_id": "R-5530"}

10. assistant

    Found it — your Steel kettle came in delivered order **R-5530** (placed 2026-10-09). Let me check where we can ship a replacement from, starting with the north warehouse.
    
    

    check_stock({"sku":"kettle-steel","warehouse":"north"})

11. tool

    {"available": 0, "sku": "kettle-steel", "warehouse": "north"}

12. assistant

    North doesn't have one. Checking south.
    
    

    check_stock({"sku":"kettle-steel","warehouse":"south"})

13. tool

    {"available": 4, "sku": "kettle-steel", "warehouse": "south"}

14. assistant

    South has one. I'll reserve a replacement from the south warehouse and ship it to your address, and set up a return for the damaged kettle.
    
    

    reserve_item({"sku":"kettle-steel","warehouse":"south","order_id":"R-5530"})

    create_return({"order_id":"R-5530","reason":"Steel kettle arrived with a cracked lid"})

15. tool

    {"reservation_id": "RS-4410", "ships_on": "2026-11-03"}

16. tool

    {"error": "damaged items are not returned: open a damage claim with open_claim instead"}

17. assistant

    The replacement is reserved. Since it's a damaged item, I'll open a damage claim rather than a standard return.
    
    

    open_claim({"order_id":"R-5530","reason":"Steel kettle arrived with a cracked lid"})

18. tool

    {"claim_id": "CL-2207", "order_id": "R-5530", "status": "open"}

19. assistant

    All sorted, Ana. Here's what I've done about your kettle (from order **R-5530**):
    
    - **Replacement:** A new Steel kettle is reserved from our south warehouse and will **ship to your address on 2026-11-03** (reference **RS-4410**). North was out of stock, so it's coming from south.
    - **Damaged item:** I've opened a damage claim for the cracked-lid kettle (reference **CL-2207**, status: open). You won't need to do anything further — the claim covers the returned item.
    
    You should receive a shipping confirmation for the replacement once it goes out on the 3rd. Is there anything else I can help with?