Pay Stub Decoder Skill
Most people can't explain a third of the lines on their own pay stub — which is exactly how errors survive for years. This skill decodes every line, shows the gross-to-net waterfall, and runs the error checklist: wrong withholding status, benefit deductions that don't match elections, missing overtime, and the retirement match that quietly isn't there.
What This Skill Produces
- Line-by-line decode — every earning, tax, and deduction in plain English
- The waterfall — gross → taxes → pre-tax deductions → post-tax → net, with percentages
- The error checklist — run against the user's stated situation, discrepancies flagged
- Payroll fixes — what to raise, with the wording
Required Inputs
Ask for these only if not provided:
- The stub — lines and amounts (redact identifiers freely; the codes and numbers are what matter)
- The expectations: stated salary/rate, hours if hourly, benefit elections (retirement %, insurance tier), filing status
- Jurisdiction — tax lines and mandatory deductions vary by country/state; never guess
- What prompted this — "smaller than expected" gets a targeted diff, not just a tour
Framework
- Codes to English: payroll abbreviations (the cryptic 6-character kind) decoded by pattern and context; anything genuinely ambiguous gets flagged ask payroll what this code means rather than guessed.
- Pre-tax vs post-tax matters: the waterfall shows where each deduction lands, because a pre-tax dollar costs less than a post-tax one — and misclassified deductions are a real error class.
- The five common errors: withholding status not matching filing reality · benefit deduction ≠ elected amount · missing/mis-multiplied overtime · retirement contribution or employer match absent or mismatched · state/locality taxes for the wrong place (remote-work classic).
- Annualize the surprises: a $38 mystery deduction is $988/year — every finding shows both numbers.
- Year-to-date is the audit trail: YTD columns catch errors the single stub hides (a match that stopped in March shows here first).
Output Format
Pay Stub Decode: [period]
The waterfall: Gross $[n] → taxes −$[n] ([n]%) → pre-tax −$[n] → post-tax −$[n] → Net $[n] ([n]% of gross)
Line decode | Line/code | Plain English | Amount | /year | Check |
⚠ Findings — each: the line, expected vs actual, the annualized gap, likely cause
For payroll: [the message: specific lines, specific asks — payroll fixes line items, not feelings]
Looks right: [the lines verified clean — decoded confidence, not just alarms]
End verbatim: "This is a plain-language reading, not tax or legal advice — payroll rules vary by jurisdiction; confirm anything load-bearing with payroll or a tax professional."
Quality Checks
Anti-Patterns
1---2name: pay-stub-decoder3description: Decode a pay stub line by line — every deduction explained, the gross-to-net story, and the errors worth catching. Use when asked to explain my pay stub, why is my paycheck smaller than expected, what are all these deductions, or check my paycheck for mistakes. Produces a line-by-line decode, the gross-to-net waterfall, the error checklist (withholding, benefits, overtime), and the fixes to raise with payroll.4---5
6# Pay Stub Decoder Skill
7
8Most people can't explain a third of the lines on their own pay stub — which is exactly how errors survive for years. This skill decodes every line, shows the gross-to-net waterfall, and runs the error checklist: wrong withholding status, benefit deductions that don't match elections, missing overtime, and the retirement match that quietly isn't there.
9
10## What This Skill Produces
11
12- **Line-by-line decode** — every earning, tax, and deduction in plain English
13- **The waterfall** — gross → taxes → pre-tax deductions → post-tax → net, with percentages
14- **The error checklist** — run against the user's stated situation, discrepancies flagged
15- **Payroll fixes** — what to raise, with the wording
16
17## Required Inputs
18
19Ask for these only if not provided:
20- **The stub** — lines and amounts (redact identifiers freely; the codes and numbers are what matter)
21- **The expectations:** stated salary/rate, hours if hourly, benefit elections (retirement %, insurance tier), filing status
22- **Jurisdiction** — tax lines and mandatory deductions vary by country/state; never guess
23- **What prompted this** — "smaller than expected" gets a targeted diff, not just a tour
24
25## Framework
26
271. **Codes to English:** payroll abbreviations (the cryptic 6-character kind) decoded by pattern and context; anything genuinely ambiguous gets flagged *ask payroll what this code means* rather than guessed.
282. **Pre-tax vs post-tax matters:** the waterfall shows *where* each deduction lands, because a pre-tax dollar costs less than a post-tax one — and misclassified deductions are a real error class.
293. **The five common errors:** withholding status not matching filing reality · benefit deduction ≠ elected amount · missing/mis-multiplied overtime · retirement contribution or employer match absent or mismatched · state/locality taxes for the wrong place (remote-work classic).
304. **Annualize the surprises:** a $38 mystery deduction is $988/year — every finding shows both numbers.
315. **Year-to-date is the audit trail:** YTD columns catch errors the single stub hides (a match that stopped in March shows here first).
32
33## Output Format
34
35### Pay Stub Decode: [period]
36
37**The waterfall:** Gross $[n] → taxes −$[n] ([n]%) → pre-tax −$[n] → post-tax −$[n] → **Net $[n]** ([n]% of gross)
38
39**Line decode** | Line/code | Plain English | Amount | /year | Check |
40**⚠ Findings** — each: the line, expected vs actual, the annualized gap, likely cause
41**For payroll:** [the message: specific lines, specific asks — payroll fixes line items, not feelings]
42**Looks right:** [the lines verified clean — decoded confidence, not just alarms]
43
44End verbatim: *"This is a plain-language reading, not tax or legal advice — payroll rules vary by jurisdiction; confirm anything load-bearing with payroll or a tax professional."*
45
46## Quality Checks
47
48- [ ] Every line is decoded or explicitly flagged ask-payroll — none skipped
49- [ ] The waterfall reconciles to the stated net to the cent
50- [ ] Findings show single-period and annualized amounts
51- [ ] The error checklist ran against the user's stated elections
52- [ ] Clean lines are affirmed, not just silent
53- [ ] The disclaimer appears verbatim
54
55## Anti-Patterns
56
57- [ ] Do not guess ambiguous codes — a wrong decode plants a wrong grievance
58- [ ] Do not treat all deductions as losses — the waterfall distinguishes taxes, savings, and benefits
59- [ ] Do not skip YTD — the single stub hides what the year reveals
60- [ ] Do not draft an angry payroll email — line numbers and expected-vs-actual get fixes; tone gets ticket queues
61- [ ] Do not give tax advice — decode what IS withheld; what SHOULD be is a professional's call
Mohit Aggarwal