{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"two-asset-portfolio"},"result":{"entity_type":"calculator","id":"two-asset-portfolio","calculator_id":"two-asset-portfolio","canonical_url":"https://tttkmbb.com/investing/two-asset-portfolio","name":"Two-Asset Portfolio Calculator","title":"Two-Asset Portfolio Calculator – Expected Return, Risk and Minimum-Variance Weights","category":"investing","category_name":"Investing & Real Estate","tool_name":"calculate_two_asset_portfolio","featured_mcp_tool":false,"description":"Computes the expected return, variance and standard deviation of a two-asset portfolio from the weights, expected returns, standard deviations and correlation, and finds the minimum-variance weight and the diversification benefit.","use_when":"You want to see how combining two assets (e.g. stocks and bonds) changes risk and return, or find the weight that minimises portfolio variance.","do_not_use_when":"The portfolio has more than two assets (a covariance matrix is needed) or you want the tangency (maximum Sharpe) portfolio. Informational only; not financial advice.","inputs":[{"name":"weight_a_percent","label":"Weight of asset A","type":"number","unit":"%","required":true,"min":0,"max":100,"description":"Share of the portfolio in asset A in percent; asset B gets the remainder.","example":60},{"name":"return_a_percent","label":"Expected return of A","type":"number","unit":"%","required":true,"min":-100,"max":1000,"description":"Expected return of asset A in percent.","example":10},{"name":"return_b_percent","label":"Expected return of B","type":"number","unit":"%","required":true,"min":-100,"max":1000,"description":"Expected return of asset B in percent.","example":5},{"name":"std_dev_a_percent","label":"Standard deviation of A","type":"number","unit":"%","required":true,"min":0,"max":1000,"description":"Volatility of asset A in percent.","example":20},{"name":"std_dev_b_percent","label":"Standard deviation of B","type":"number","unit":"%","required":true,"min":0,"max":1000,"description":"Volatility of asset B in percent.","example":8},{"name":"correlation","label":"Correlation","type":"number","required":true,"min":-1,"max":1,"description":"Correlation coefficient between the two assets' returns (−1 to 1).","example":0.2}],"outputs":[{"name":"expected_return_percent","label":"Portfolio expected return","type":"number","unit":"%","decimals":2,"description":"wA·rA + wB·rB."},{"name":"portfolio_variance","label":"Portfolio variance","type":"number","unit":"%²","decimals":4,"description":"wA²·σA² + wB²·σB² + 2·wA·wB·ρ·σA·σB (in percent squared)."},{"name":"portfolio_std_dev_percent","label":"Portfolio standard deviation","type":"number","unit":"%","decimals":2,"description":"Square root of the variance."},{"name":"covariance","label":"Covariance","type":"number","unit":"%²","decimals":4,"description":"ρ·σA·σB."},{"name":"min_variance_weight_a_percent","label":"Minimum-variance weight of A","type":"number","unit":"%","decimals":2,"description":"(σB² − ρ·σA·σB) / (σA² + σB² − 2·ρ·σA·σB), clamped to 0–100 %."},{"name":"min_variance_std_dev_percent","label":"Minimum-variance standard deviation","type":"number","unit":"%","decimals":2,"description":"Portfolio volatility at the minimum-variance weight."},{"name":"diversification_benefit_percent","label":"Diversification benefit","type":"number","unit":"%","decimals":2,"description":"Weighted average of the two volatilities minus the portfolio volatility (0 when ρ = 1)."}],"input_schema":{"type":"object","properties":{"weight_a_percent":{"description":"Share of the portfolio in asset A in percent; asset B gets the remainder. 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