# Contract — F5-conf-01
**Question.** Walrasian equilibrium of a 2-agent, 2-good Cobb–Douglas exchange economy (good 2 numeraire, p2=1).
**Estimands.** p = p1/p2 (closed form); allocation x1_A,x2_A,x1_B,x2_B; aggregate excess demand of good 1 at p (should be 0); Walras residual p*z1+z2 (identically 0); independent numerical root of z1(p)=0.
**Assumptions.** Cobb–Douglas with 0<alpha_i<1 (interior demands), strictly positive endowments/wealth, p2=1 normalisation, price-taking agents. Closed form: p = sum_i alpha_i e2_i / sum_i (1-alpha_i) e1_i.
**Outputs.** out/results.json (task_id, price_ratio_p1_over_p2, x1_A,x2_A,x1_B,x2_B, excess_demand_good1, walras_law_residual, aggregate_endowment_good1/2, price_ratio_numerical, feasibility, feasibility_reason, data_issues, n_input_rows, n_analysed, random_seed); out/report.md (6 sections); out/analysis.py; out/claims.json.
**Information rules.** Only data/ files; numerical validation must root-find z1(p), not evaluate closed form; every data problem goes in data_issues.
**Invalidity.** alpha outside (0,1), non-positive endowments, missing agents, or inconsistent aggregates without a documented resolution.