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Code RoomUnverified library dependencies
EasyPrep Room Coding #4339

Unverified library dependencies

Vibe & agenticAlgorithms & data structuresEntry–Mid~10 min

You asked an AI assistant for a JavaScript helper to format a phone number, and it handed you 15 lines using a regex and a library import you've never seen: `import phoneFmt from 'phone-formatter-pro'`. It looks clean and you're tempted to paste it in and move on. Before you do, what do you actually check, and in what order — without just running it and hoping?

Implement
format_us_phone(raw: str) → str
Examples
in["5551234567"]out"(555) 123-4567"
in["+1 (555) 123-4567"]out"+1 (555) 123-4567"
What a strong answer looks like

Treat the AI’s output as a draft to verify, not an answer to trust. Name the specific flaw and the input that triggers it, say how you’d catch it (tests, edge cases, reading critically), and how you’d re-prompt or decompose to get it right.

0:00 of about 10 min

Vibe & agentic: describe the solution in plain language (or narrate it) and the coach grades your approach.

Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.