401k-plan-decoder

1# 401k Plan Decoder Skill
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3Nobody reads the 401k enrollment packet, which is how a 0.9% expense ratio quietly eats six figures of a career's compounding. This skill reads it: what the funds actually cost in dollars over time, what the match really promises once vesting and true-up fine print are applied, and which plan features (Roth option, brokerage window, loan terms) matter for this person. It decodes cost and structure — it never picks investments.
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5## What This Skill Produces
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7- The fee decode: each relevant expense ratio and admin fee converted to dollars-over-career on the user's numbers
8- Match math with the fine print applied: per-paycheck vs. annual true-up, vesting schedule, what leaving at year N forfeits
9- Fund-lineup triage by cost tier — where the cheap broad-market building blocks are, and which funds cost 10× a near-identical neighbor
10- Feature decode (Roth 401k, after-tax + conversions if offered, loans, brokerage window) and the questions for HR/administrator
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12## Required Inputs
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14Ask for these only if they aren't already provided:
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16- **The plan documents** — fund lineup with expense ratios (the fee disclosure / 404a-5 notice is the gold source), match formula, vesting schedule, summary plan description excerpts. Decode what's provided; list what's missing by name.
17- **Their numbers** — salary, current contribution %, balance, and age band — needed to make fees and match concrete.
18- **Tenure expectation** — vesting math is meaningless without it.
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