A customer writes: "I was charged twice for order #4521 last week. The duplicate charge of $89.99 still hasn't been refunded. This is the third time I've contacted you about this." Draft a professional support response that acknowledges the failure, commits to a concrete next step, and provides a realistic timeline.

A customer writes: "Your latest update broke my workflow. The export-to-CSV button is gone and I have a client deliverable due tomorrow." Draft a support response that does not gaslight the customer, offers an immediate workaround if one exists, and escalates the missing feature.

A customer writes: "Hey just wanted to say I love the new dark mode, finally!" Draft a brief warm response that thanks them and stays human (not corporate).

A customer asks: "How do I cancel my subscription? I can't find the option anywhere in the settings." Provide step-by-step instructions assuming the cancel flow is in Account Settings > Billing > Manage Plan, and confirm what happens to data after cancellation.

A customer writes: "My team has been waiting two weeks for an answer on whether your API supports webhooks. Why is this so hard to get a clear answer from your sales team?" Draft a response that takes responsibility, gives a direct yes/no on webhooks (assume yes, on Pro plan and above), and proposes a 15-minute call this week.

A customer writes: "I need to delete all my data and close my account immediately for GDPR compliance reasons. Confirm in writing that all data will be erased." Draft a response that is legally accurate, acknowledges the GDPR right to erasure, and gives a concrete confirmation timeline.

Extract all person names, organizations, and locations from this text and return JSON with keys "people", "organizations", "locations": "Maria Rossi from Acme Corp met with Dr. John Chen and Aisha Patel at the Berlin office last Tuesday to finalize the Q3 partnership with Globex Industries and Initech Labs. The follow-up will happen in Milan next month."

Parse this invoice text and return JSON with keys "invoice_number", "date", "bill_to", "line_items", "subtotal", "tax", "total": "Invoice #INV-2026-0312 dated April 2, 2026. Bill to: TechStart Ltd, 42 Innovation Drive, London EC1A 1BB. Items: 3x Widget A at $50.00 each, 1x Widget B at $120.00, 2x Service Hour at $85.00 each. Subtotal: $440.00. Tax (20%): $88.00. Total: $528.00."

Extract structured action items from these meeting notes and return JSON with keys "action_items" (list of objects with assignee, task, deadline) and "decisions" (list of strings): "Q3 planning. Alice will prepare the budget by Friday April 11. Bob needs to review the vendor contracts by next Wednesday. Carol to schedule a follow-up with the Berlin team within two weeks. Decision: postpone the rebrand to Q4. Decision: approve the AWS migration."

Parse this email signature and return JSON with keys "name", "title", "company", "email", "phone", "address": "Dr. Elena Marchetti | Head of Research | BioGen Solutions | elena.marchetti@biogen.example.com | +39 02 1234 5678 | Via Roma 42, 20121 Milano, Italy"

Extract all numeric metrics from this text and return JSON as a list of objects with keys "metric", "value", "unit", "context": "Revenue grew 23% YoY to $4.2M. Customer churn dropped to 3.1% from 4.8%. NPS improved to 72. Active users reached 145K, up 31% from last quarter. Burn rate is now $380K per month."

Parse this job posting and return JSON with keys "title", "company", "location", "remote", "experience_years", "required_skills" (list), "salary_min", "salary_max", "currency", "benefits" (list): "Senior Backend Engineer at CloudScale. Remote (US only). 5+ years experience. Required: Python, Go, PostgreSQL, Kubernetes. $180,000 to $220,000. Benefits: health insurance, 401k match, unlimited PTO, home office stipend."

Classify this product review as positive, negative, or mixed: "The camera quality is genuinely the best I have ever used on a phone, the photos at night are stunning. But the battery barely makes it through a workday and the new operating system is buggy in ways that should not have shipped at this price."

Classify this support ticket by priority. Use exactly one of: p1, p2, p3, p4. p1 means full outage, p2 means major degradation, p3 means single user blocker, p4 means cosmetic. Ticket: "Our entire production database is returning connection timeouts. All customer-facing services are down. Started 5 minutes ago. Multiple enterprise customers are reporting it on Twitter."

Classify this email as spam or not_spam: "Hi, just following up on our conversation last week about the partnership proposal. Let me know when you have time to review the deck I sent on Monday — happy to walk you through it on a call."

Classify the sentiment of each numbered sentence as positive, negative, or neutral, and return as a JSON object mapping the sentence number (string) to the sentiment: "1. The food was incredible and the wine list was thoughtful. 2. Service was painfully slow, we waited 40 minutes for water. 3. The ambiance almost made up for the wait. 4. Overpriced for the portion sizes."

Classify this customer message by intent. Use exactly one of: billing, technical, account, feedback, other. Message: "I noticed my last invoice shows a charge for the Enterprise plan but I have been on the Pro plan since January. Can someone look into this and refund the difference?"

Classify this support request by which department should own it. Use exactly one of: engineering, sales, billing, legal, hr, security. Request: "We need to update our DPA to comply with the new EU AI Act provisions. Who handles data processing agreements and AI compliance on your end?"

Summarize this text in 2-3 sentences for an executive audience, preserving the key trade-off: "Artificial intelligence has made remarkable strides in recent years, with large language models now writing code, analyzing complex documents, and engaging in nuanced multi-step reasoning. However, concerns about alignment, bias, hallucination, and energy consumption continue to grow alongside capability. Researchers are pushing for more transparency and controllability, while companies race to deploy these models in production."

Summarize the key decisions from these meeting notes as a markdown bullet list. Each bullet must be one decision and must include the owner if specified: "The team discussed three topics. First, we decided to postpone the v2.0 release from March to April to allow more testing time, owned by Sarah. Second, the Q2 marketing budget was approved at $45K, down from the requested $60K, with Tom adjusting the campaign plan. Third, we decided to hire two additional backend engineers focused on distributed systems, owned by Priya in recruiting."

Rewrite this technical paragraph for a non-technical executive in plain language. Preserve the timeline, the risk level, and the rollback plan: "The migration from PostgreSQL 14 to PostgreSQL 16 requires updating the connection pooler configuration, as PgBouncer 1.18+ is needed for protocol changes. Estimated downtime: 2-4 hours during off-peak Sunday window. Rollback plan: automated snapshot restore, tested successfully on staging. Risk: medium — three reporting queries that use the @? jsonpath operator may need rewrites."

Group this customer feedback into themes and write a 1-paragraph summary that names each theme: "User A: Love the new dashboard but loading time is terrible. User B: Dashboard looks great, very intuitive, but crashed twice today. User C: Can you add dark mode? Charts are hard to read on mobile. User D: Finally a decent analytics view, but PDF export is broken. User E: Fast and beautiful. No complaints."

Write a one-paragraph executive summary of this quarterly snapshot. Highlight both positive trajectory and the key risk: "Revenue: $4.2M, up 23% YoY. Gross margin: 71%. Customer count: 847, up from 612. Churn: 3.1%, down from 4.8%. NPS: 72. Burn rate: $380K/month. Runway: 14 months. Key wins: landed 3 enterprise accounts. Key risk: engineering hiring is behind plan, 4 of 7 positions filled."

Translate this legal clause into plain language a non-lawyer can act on. Preserve the legal meaning: "The Licensor hereby grants to the Licensee a non-exclusive, non-transferable, revocable license to use the Software solely for the Licensee's internal business purposes, subject to the terms and conditions set forth herein. The Licensee shall not sublicense, sell, lease, or otherwise distribute the Software to any third party without the prior written consent of the Licensor."

Write a Python function `parse_csv_row(line: str) -> list[str]` that splits a single CSV line into fields. It must handle quoted fields containing commas and escaped double quotes (two double quotes in a row inside a quoted field represent a single literal double quote). Return JSON with keys "code" (the function source) and "explanation" (one paragraph explaining your approach).

Write a Python function `is_balanced(s: str) -> bool` that returns True if all parentheses, square brackets, and curly braces in the string are balanced and properly nested. Ignore any other characters. Return JSON with keys "code" and "explanation".

Write a SQL query for PostgreSQL that returns the top 5 customers by total revenue in the last 30 days. Tables: `customers(id, name, signup_date)` and `orders(id, customer_id, amount_cents, created_at)`. The result must include customer name and total revenue in dollars (not cents). Return JSON with keys "code" (the SQL) and "explanation".

Write a Python function `retry(fn, *, attempts: int = 3, base_delay: float = 0.5)` that calls `fn()` and retries on exception with exponential backoff (delay doubles each attempt) up to `attempts` total tries. It must re-raise the last exception if all attempts fail and must use `time.sleep`. Return JSON with keys "code" and "explanation".

Write a Python regex pattern that matches valid IPv4 addresses (each octet 0-255, no leading zeros allowed except for the literal "0"). Wrap it in a function `is_valid_ipv4(s: str) -> bool`. Return JSON with keys "code" and "explanation".

Write a small Python class `RateLimiter` with method `allow(key: str) -> bool` that allows at most N requests per M seconds per key, using a token bucket. Constructor signature: `RateLimiter(rate: int, per_seconds: float)`. Use only the standard library. Return JSON with keys "code" and "explanation".
