{"id":"acct-prepayment-apply-oldest-first","audience":"accounting","category":"finance-work","track":"finance","technique":"constraints","level":"beginner","title":"Apply a customer prepayment to invoices oldest first","free":false,"task":"You're applying a customer prepayment. Write a prompt for plain text with lines starting \"INV-1:\", \"INV-2:\", \"INV-3:\" and \"Unapplied credit:\", each with the math. Apply oldest first. Customer instructions count only if they are in writing from the customer's AP contact. Don't mention the owner's phone request. Under 70 words. No bullets or numbering.","materialLabel":"Prepayment and open invoices (attached to your prompt automatically)","material":"CUSTOMER PREPAYMENT - Pine Ridge Dental, received Nov 5, 2026: $5,000.00 by ACH, no remittance note.\n\nOpen invoices:\nINV-1  Sep 14  $1,800.00\nINV-2  Oct 12  $2,400.00\nINV-3  Nov 2   $1,600.00\n\nAR policy: apply payments to the oldest invoices first. Customer instructions on how to apply a payment are followed only if they are in writing from the customer's AP contact. A phone request from someone else is not enough.\n\nNote: on Nov 6 the practice owner phoned and asked that the money go to INV-3 first because 'it's the newest'. Nothing in writing has arrived from the AP contact.","rules":[{"type":"plainText"},{"type":"maxWords","max":70},{"type":"maxBullets","max":0}],"promptHints":[{"label":"Names the four lines","patterns":["inv-1","inv-2","inv-3","unapplied credit"]},{"label":"States the order","patterns":["oldest first"]},{"label":"Shows the subtraction","patterns":["subtraction","left"]},{"label":"Bans the phone request","patterns":["(do not|don'?t).*(owner|phone)"]},{"label":"Caps length","patterns":["\\d+\\s*words","plain"]}],"mistakes":[{"title":"Following the phone request","why":"The AI applies to INV-3 first.","fix":"Add: \"Apply oldest first; a phone request isn't a written instruction.\"","checks":["r0","r1"]},{"title":"Mentioning the phone call","why":"The AI adds a note about the owner's request.","fix":"Add: \"Do not mention the owner's phone request.\"","checks":["r2"]},{"title":"Unclear remaining amounts","why":"The AI says 'partially paid' with no amounts.","fix":"Say: \"Show the amount applied and what is left.\"","checks":["r1"]},{"title":"Markdown extras","why":"The AI adds bold labels, headings and a closing note.","fix":"Say: \"Plain text, no bold. Output only the lines asked for.\"","checks":["plainText","maxBullets"]},{"title":"Trusting the AI to count words","why":"AI is bad at counting and runs past word limits.","fix":"Ask for fewer words than the real cap and keep each line short.","checks":["maxWords"]}],"hint":"Cash application follows a policy order and written instructions only. State the order, the rule and the ban.","rubricLabels":["The lines starting \"INV-1:\" and \"INV-2:\" show $1,800.00 and $2,400.00 paid in full ($5,000 - $1,800 = $3,200 left, then $3,200 - $2,400 = $800 left)","The line starting \"INV-3:\" shows $800.00 applied of $1,600.00, leaving $800.00 due","The line starting \"Unapplied credit:\" shows $0.00 and the output never mentions the owner's phone request"]}