# Versioned contracts

This directory is the machine-readable contract surface for policy, event and outcome-metric definitions.

- `policies/sell-policy-contract.v1.json`: approved research-candidate implementation values; SHA-256 `a269a0331b83c0f6ec108e7587de1d20c798036ff8d0c03d726cd854e73d8480`.
- `events/signal-decision-created.v2.schema.json`: immutable outbox payload contract.
- `metrics/outcome-metrics.v1.json`: proposed metric definitions; Quant/Risk approval is still required.

The C# constants are intentionally checked against the policy JSON by `scripts/validate_v123.py`. A changed value without a Model Change record, Golden vectors and OOS impact evidence blocks G2.
