Parametric Index Deriver

Deterministically aggregates a named metric (mean, sum, count, max, or min) across a receipt set into a parametric index value: receipts as an oracle replacement, replay-on-challenge instead of trust-the-feed. Feeds the shipped compute_parametric_trigger_payout kernel, which performs the actual trigger-vs-payout math; this kernel never reimplements that logic. The index is a replayable derived value, never a settlement trigger by itself. Not the same as check_agency_eligibility_matrix or any lending eligibility tool -- this is an insurance-evidence parametric index. Zero network, zero PII.

Tool URL: https://ainumbers.co/chaingraph/art-309-parametric-index-deriver.html AP2/Policy Mandate export: yes