College Cost Skill
The two numbers that matter — the true all-in cost, and the monthly payment for the decade after — appear nowhere on the marketing or, tellingly, the financial-aid letter, which routinely blends grants (free) with loans (very much not) into one cheerful "award." This skill computes both numbers: net cost per year with aid honestly sorted, inflated forward (tuition outruns CPI), split into cash and borrowed, and the borrowed part converted into the graduate's first decade of monthly reality. Two offers become comparable the moment both are run through it.
What This Skill Produces
- The all-in number — net 4-year cost, cash vs. borrowed, from the script
- The offer decode — the award letter's lines sorted: grants/scholarships (free) vs. loans (repaid) vs. work-study (earned) — the blend untangled
- The monthly tail — the post-graduation payment, term, and total interest, stated next to a starting-salary reality check
- The comparison — two+ schools on identical assumptions, which the letters never are
Required Inputs
Ask for these if not provided:
- The sticker — full cost of attendance (tuition + room/board + fees, not tuition alone — the letter's fine print has it)
- The aid, sorted — the award letter's actual lines; anything ambiguous gets decoded ("award" ≠ grant until proven), and renewal conditions noted (GPA floors, year-one-only grants — the classic bait)
- The family math — what's payable in cash per year without borrowing; the gap is the loan share
- The candidate schools — for comparisons, each letter, same treatment
Programmatic Helper
python3 scripts/college_cost.py --sticker 32000 --aid 14000
python3 scripts/college_cost.py --sticker 32000 --aid 14000 --loan-share 60 --loan-apr 6.5 --json
Deterministic. Defaults: 4% cost inflation, 4 years, 50% loan share at 6.5% over 10 years — all overridable; the true-all-in line includes the loan interest the sticker never mentions.
Framework: The Honest-Number Rules
- Sort the award letter before believing it: grants and scholarships reduce cost; loans defer it with interest; work-study is a job. Letters present all three as "aid" — the decode re-sorts, and the net price is what remains after only the free money.
- Renewal conditions are the letter's fine print trap: a year-one grant that needs a 3.5 GPA, or doesn't renew at all, makes year one's net price a teaser — the model runs the conservative case (aid as-guaranteed) beside the hopeful one and shows the spread.
- The monthly tail is the decision's true unit: $454/month for ten years means something a $79,887 total doesn't — the output states it next to typical starting salaries for the intended field (as a sanity band, not a prophecy), because the loan-to-income ratio is the affordability question.
- The fifth-year risk is a real input: graduation-in-four is an assumption; a fifth year adds a full year of net cost and delays income. Schools' actual 4-year graduation rates vary enormously and are public — the checklist sends the user to look theirs up.
- Compare schools on identical assumptions: same inflation, same loan terms, each school's own aid — the script run twice; a $10k/year difference compounds through interest into a much larger true-all-in gap, and the cheaper-sticker school is not always the cheaper school once aid sorts differently.
Output Format
College Cost: [school(s)]
The All-In Number
[Script output: per-year table, net total, cash/borrowed split, the loan tail, true all-in]
The Offer, Decoded
| Letter line |
Actually is |
Counts against cost? |
Renewal condition |
The Monthly Tail
[Payment/term/interest · against the field's starting-salary band, labeled as a band · the loan-to-income read]
[If comparing] The Table
[School × (net total · borrowed · monthly tail · true all-in) — same assumptions, stated]
Aid renewal terms and loan programs vary; verify each with the school and servicer. Educational model, not financial advice — and the graduation-rate lookup is homework worth doing.
Quality Checks
Anti-Patterns
1---2name: college-cost3description: Compute what a degree will actually cost — sticker minus real aid, inflated per year, split into cash and loans, with the loan's decade-long monthly tail made visible before enrollment instead of after. Use when asked what will college really cost, compare these two offers' real prices, how much loan payment after graduation, or is this school affordable. Produces the all-in number from the script, the offer-letter decode (grants vs loans untangled), the monthly-tail reality check, and the two-school comparison.4---5
6# College Cost Skill
7
8The two numbers that matter — the true all-in cost, and the monthly payment for the decade after — appear nowhere on the marketing or, tellingly, the financial-aid letter, which routinely blends grants (free) with loans (very much not) into one cheerful "award." This skill computes both numbers: net cost per year with aid honestly sorted, inflated forward (tuition outruns CPI), split into cash and borrowed, and the borrowed part converted into the graduate's first decade of monthly reality. Two offers become comparable the moment both are run through it.
9
10## What This Skill Produces
11
12- **The all-in number** — net 4-year cost, cash vs. borrowed, from the script
13- **The offer decode** — the award letter's lines sorted: grants/scholarships (free) vs. loans (repaid) vs. work-study (earned) — the blend untangled
14- **The monthly tail** — the post-graduation payment, term, and total interest, stated next to a starting-salary reality check
15- **The comparison** — two+ schools on identical assumptions, which the letters never are
16
17## Required Inputs
18
19Ask for these if not provided:
20- **The sticker** — full cost of attendance (tuition + room/board + fees, not tuition alone — the letter's fine print has it)
21- **The aid, sorted** — the award letter's actual lines; anything ambiguous gets decoded ("award" ≠ grant until proven), and renewal conditions noted (GPA floors, year-one-only grants — the classic bait)
22- **The family math** — what's payable in cash per year without borrowing; the gap is the loan share
23- **The candidate schools** — for comparisons, each letter, same treatment
24
25## Programmatic Helper
26
27```bash
28python3 scripts/college_cost.py --sticker 32000 --aid 14000
29python3 scripts/college_cost.py --sticker 32000 --aid 14000 --loan-share 60 --loan-apr 6.5 --json
30```
31
32Deterministic. Defaults: 4% cost inflation, 4 years, 50% loan share at 6.5% over 10 years — all overridable; the true-all-in line includes the loan interest the sticker never mentions.
33
34## Framework: The Honest-Number Rules
35
361. **Sort the award letter before believing it:** grants and scholarships reduce cost; loans *defer* it with interest; work-study is a job. Letters present all three as "aid" — the decode re-sorts, and the net price is what remains after *only the free money*.
372. **Renewal conditions are the letter's fine print trap:** a year-one grant that needs a 3.5 GPA, or doesn't renew at all, makes year one's net price a teaser — the model runs the conservative case (aid as-guaranteed) beside the hopeful one and shows the spread.
383. **The monthly tail is the decision's true unit:** $454/month for ten years means something a $79,887 total doesn't — the output states it next to typical starting salaries for the intended field (as a sanity band, not a prophecy), because the loan-to-income ratio is the affordability question.
394. **The fifth-year risk is a real input:** graduation-in-four is an assumption; a fifth year adds a full year of net cost *and* delays income. Schools' actual 4-year graduation rates vary enormously and are public — the checklist sends the user to look theirs up.
405. **Compare schools on identical assumptions:** same inflation, same loan terms, each school's own aid — the script run twice; a $10k/year difference compounds through interest into a much larger true-all-in gap, and the cheaper-sticker school is not always the cheaper school once aid sorts differently.
41
42## Output Format
43
44---
45
46# College Cost: [school(s)]
47
48## The All-In Number
49[Script output: per-year table, net total, cash/borrowed split, the loan tail, true all-in]
50
51## The Offer, Decoded
52| Letter line | Actually is | Counts against cost? | Renewal condition |
53|---|---|---|---|
54
55## The Monthly Tail
56[Payment/term/interest · against the field's starting-salary band, labeled as a band · the loan-to-income read]
57
58## [If comparing] The Table
59[School × (net total · borrowed · monthly tail · true all-in) — same assumptions, stated]
60
61*Aid renewal terms and loan programs vary; verify each with the school and servicer. Educational model, not financial advice — and the graduation-rate lookup is homework worth doing.*
62
63---
64
65## Quality Checks
66
67- [ ] The letter is sorted before the math — no loan counted as aid
68- [ ] Renewal conditions produce a conservative-case run beside the hopeful one
69- [ ] The monthly tail appears with the loan-to-income framing
70- [ ] Comparisons use identical assumptions with each school's own aid
71- [ ] The fifth-year risk and graduation-rate homework are named
72
73## Anti-Patterns
74
75- [ ] Do not accept "total aid" as a discount — the sort is the whole skill
76- [ ] Do not model tuition flat — it inflates faster than most things families budget with
77- [ ] Do not present the total without the monthly tail — the decade is the decision
78- [ ] Do not compare letters as written — they're formatted to resist exactly that
79- [ ] Do not editorialize school choice — price it honestly; worth is the family's call
gabrielmoreira