Reproduce the fixed CPI result

Unzip the complete static release into an empty directory. Python 3.10+ standard library is sufficient. No installation, credentials, environment file or network is required.

python -I -B cpi_verify.py --root . --manifest-sha256 SHA256_FROM_DISTRIBUTOR

Run from the extracted root. The distributor supplies the exact DELIVERY-MANIFEST.json digest separately. A digest calculated only from the same untrusted download checks consistency, not authenticity.

Download the consumer · Full runnable instructions and direct baseline · Release manifest

The fixed query is country GB, month 2024-12, measure year_over_year, unit percent. For example, --month 2025-01 exits nonzero with UNSUPPORTED_QUERY; it never interpolates.

Inspect the CPI example Sample JSON · Evidence JSON

What verification establishes

Files match the supplied manifest digest; the unchanged proof matches its ID and query/version; both source observations reproduce the preserved result. The parent hash is a reference, not a membership proof: this small package does not independently re-fetch ONS or verify the full parent.

Prepared offline on 12 November 2026. Public hosting and remote API/MCP access are not open. These are historical snapshots, not a live feed.