Reproducible synthetic release capsules¶

build_release_capsule bundles actual controlled generator configurations, versions, seed commitments, provenance digests, privacy/utility evidence outcomes, permissive SPDX declarations and artifact hashes/sizes in canonical JSON. Artifact content, raw prompts, private paths and reference records are not embedded. Equivalent generator/artifact ordering produces identical bytes.

verify_release_capsule requires the matching local artifact bytes, reconstructs the strict canonical capsule and refuses missing, extra, changed or unlicensed assets and altered metadata. Verification is offline. Failed or unevaluated checks remain explicit and never become a passing qualification.

The verifier distinguishes external_model_required from a recipe whose dependencies are declared locally. It always reports generation_reproduced=false: verifying commitments does not regenerate a corpus. Retain local seed material, generator code, pinned runtime and authorized dependencies to perform independent regeneration. Commitments are not signatures or proof that declarations are true. Passing integrity checks does not authorize publication or establish privacy, clinical utility, source rights or a release gate.

Each capsule has bounded generators, artifacts and scalar configuration options. String options must be controlled codes; approved vocabularies and independent provenance review remain caller responsibilities. Only explicitly synthetic corpora belong in this workflow; metadata checks cannot identify real records.