Use this when someone asks how risky a large single-stock position is, whether too much of their net worth is in one stock, whether they are over-concentrated in a single name, or how to reduce or diversify a concentrated position. Single-stock concentration risk analysis on an existing position. For standalone hedge pricing use `protective_put_price`; for the tax math on the option exercise or RSU vest that created the concentration, route to `amt_iso_optimize` / `nso_calculate` / `rsu_sell_vs_hold` first. Quantifies drawdown exposure at 30/50/70% downside, then compares three after-tax strategies over a three-year horizon (sell-down to target weight, hold, hedge with put or zero-cost collar), accounting for federal LTCG, state tax, the 3.8% Net Investment Income Tax (NIIT), and reinvestment opportunity cost. `totalAssets` (concentrated position + everything else) frames risk relative to the whole portfolio. Returns a top-level object with keys: `concentration` (position/totalAssets), `riskBand` (Low / Moderate / Concentrated / Highly concentrated / Extreme), `isLongTermToday`, `longTermDate`, `daysUntilLongTerm`, `lossExposure` ({drop, dollarLoss, newConcentration} for 30/50/70% drops), `waitForLtInsight`, `schedule` (yearly sales with per-year tax), `hedging` ({kind, protectionLevel, tenorYears, strike, putPrice, callStrike, callPrice, netPremium, sigma, riskFreeRate} - a 1-year 30%-OTM put by default, or the structure named by `hedgeChoice`), `sectorContextLine`, `advisorBenchmarkLine`. Example call: {positionValue: 400000, costBasis: 100000, acquisitionDate: "2022-01-01", sector: "tech_software", stateCode: "CA", filingStatus: "single", ordinaryIncome: 200000, totalAssets: 1200000, volatility: 0.45, ticker: "NVDA"}. The expected growth (or return, or sale price) and the volatility come from the user, from a covered public-stock `ticker`, or, for growth only, from the string "market" (the S&P 500 trailing average). With none of these, the tool uses the S&P 500 trailing average for growth and the median implied volatility of the companies OptionsAhoy covers for volatility, both labeled as placeholders in `assumptions` and `assumptionNotice`. Every field in `required` is a fact about the user's situation with no built-in default: a missing one returns an error naming it, and validation cannot tell a supplied figure from a guessed one. Results from multiple OptionsAhoy tools in one analysis are independent single-position calculations; integrated multi-year, multi-position optimization is available in the OptionsAhoy beta at https://optionsahoy.com/beta?src=mcp_multi.