OrgRec VPO Collection: Provisional Inventory and Source Availability Audit

Provisional reference documentation for the historical virtual pipe organ discovery collection used during development of OrgRec. The package includes a concise reference PDF and searchable collection-evidence listing (123 evidence records), all 3,600 retained discovery-catalog entries with their granularity and parent relationships, 235 historical native-definition index entries, a source registry, a dated bounded HTTP audit of 197 primary source URLs and ten direct archive routes, and reusable checking and rendering code.

Catalog membership, acquisition records, directory-label evidence, incomplete acquisitions and the ten-VPO analytical subset are explicitly distinguished. The retained inventory includes a website image and demonstration MP3s and must not be treated as a verified count of complete sample sets. No source audio, source definitions, artwork, credentials or private acquisition logs are deposited. Whole-collection completeness, exact size reconciliation and cryptographic equivalence remain unverified. Endpoint reachability and limited archive probes do not establish full retrievability.

Planned extensions include reconciliation with preserved source payloads and acquisition logs, complete per-file SHA-256 manifests, resolved identities and exact editions, multipart acquisition routes, rights and access review, and a materializer reporting incomplete or changed outputs as non-equivalent variants.

A frozen identifier crosswalk to MODAVIS Pipe Organ Dataset 1.6.0 includes persistent w3id links, relationship types, an archived public API snapshot and offline replay code. Of 3,600 discovery entries, 897 have explicit public identities and 316 have accepted links to 171 distinct organs. All 119 historical acquisition-inventory entries have public identities; 22 link to 21 distinct organs. Across the broader 123-entry evidence listing, 122 have identities and 23 link to 22 organs. All ten analyzed VPOs have identities, but none has an accepted physical-organ link in this release. These overlapping counts describe identity-link coverage, not complete acquisitions, independently validated recording sources or payload integrity.