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Find the emails

extraction · GPT-5.4 nano · GPT-4.1 nano · Claude Haiku 4.5 · Claude Sonnet 5

The prompt (verbatim, sent to every lane)

Extract every email address from the text below. Normalize spelled-out addresses (e.g. "x DOT y AT z DOT com" becomes x.y@z.com). Reply with the unique addresses only: lowercase, sorted alphabetically, one per line, nothing else.

Contact ops@LedgerLane.co.uk for invoices. Marketing wants you to cc mara DOT chen AT ledgerlane DOT com — she hates spam. JT prefers jt+receipts@mail.ledgerlane.co.uk (the plus tag keeps his inbox sorted). The old alias ops@ledgerlane.co.uk still works, and the Slack handle @finance-bot is not an email.
How scoring works

Unique, lowercase, sorted, one per line — exact match against the three correct addresses. WRONG lanes show the first mismatch position. Scoring strips leading/trailing whitespace and one wrapping pair of code fences or quotes before it judges — content over ceremony. Winner rule: correct → cheapest → fastest.

Prices as listed by OpenAI and Anthropic, July 2026. Costs come from provider usage fields × list prices — nothing is invented.