tiangong-pcr-library

An immutable, indexed snapshot of TianGong LCA product category rules (PCRs) and data-production methodology for fully offline use. This is a content package: use tiangong-pcr to browse, resolve, read guidance, and verify the snapshot.

Contents

| File | Purpose | | --- | --- | | library.sqlite | Indexed catalog, PCR and module content, classification coverage, mappings, and compatibility aliases | | library.sqlite.json | Snapshot version, source commit, source fingerprint, format version, and integrity hashes | | README.md, LICENSE, NOTICE.md | Usage instructions, MIT license, and source notices |

The snapshot contains English Markdown and structured YAML. Original manifests retain source language metadata, but installed document availability is en-US only. Selected document bodies are read on demand; catalog browsing uses indexes. The package has no JavaScript API, executable install scripts, runtime dependencies, or automatic downloads.

Install and verify

The CLI requires Node.js 24.19 or later, on Linux x64, Windows x64, or macOS ARM64. In a project directory:

npm install tiangong-pcr tiangong-pcr-library
./node_modules/.bin/tiangong-pcr library info --library ./node_modules/tiangong-pcr-library/library.sqlite --format json
./node_modules/.bin/tiangong-pcr library verify --library ./node_modules/tiangong-pcr-library/library.sqlite --format json
./node_modules/.bin/tiangong-pcr list --library ./node_modules/tiangong-pcr-library/library.sqlite --format json

On Windows, use node_modules/.bin/tiangong-pcr.cmd. Explicit --library selection makes the chosen snapshot unambiguous. PCR_LIBRARY can also select it; outside a PCR source checkout the CLI otherwise discovers the installed content package.

Move to an offline machine

Download the required versions on a connected machine:

npm pack [email protected]
npm pack [email protected]

Transfer both tarballs and a suitable Node.js runtime. Then install without registry access:

npm install --offline --ignore-scripts --no-audit --no-fund ./tiangong-pcr-0.1.1.tgz ./tiangong-pcr-library-0.1.1.tgz
./node_modules/.bin/tiangong-pcr library verify --format json

You can also extract library.sqlite and library.sqlite.json and copy them together to any directory. Keep the pair intact and select the database with --library /path/to/library.sqlite. No source repository checkout is needed.

Pinning and updates

The content version is independent of the CLI version; compatibility is checked through the snapshot format version. Keep old snapshots when reproducibility matters, install a new version alongside them, verify it, and explicitly select it for new work. Do not edit the database or its sidecar in place.

Record the content version, tool version, source commit, and snapshot SHA-256 from library info / library verify. Use --library-sha256 sha256:<digest> with a hash obtained from trusted release metadata to pin exact database bytes. Integrity checks do not establish trust in an unknown publisher.

PCR lifecycle and readiness are preserved. Candidate methodology remains review-required, legacy identifiers may redirect to coverage information, and an unmapped classification does not imply an available PCR.

Documentation and license

• PCR documentation
• Source and issues
• Offline format and release contract

TianGong-authored content is licensed under the MIT License; see the included LICENSE. Source citations and third-party notices remain applicable. This license does not relicense external standards or publications referenced by the methodology.