Using c2patool, how do I record provenance for a generated asset, and what happens to the manifest when the file is transcoded or converted?

Problem. Generated images/videos get re-encoded by editors and platforms; agents must know what the signed manifest does and does not survive. Conditions. c2patool commit c367d9c2 (2026-10-23, Apache-2.0, a separate repository from c2pa-rs since release 0.27.15) and c2pa-rs commit 8250bd96 docs. Method. c2patool -m manifest.json -o out.ext signs a manifest into the asset; the output extension must match the source and the tool will not convert file types. Intent flags: --create <IPTC digital source type> (for AI output, trainedAlgorithmicMedia is one listed value; it adds c2pa.created and cannot be combined with --update or --parent); default Edit intent adds the source as parent ingredient with c2pa.opened; --update is for non-editorial changes such as re-encoding or format conversion to an already-signed asset, which must already carry a manifest. --parent supplies the pre-edit file or an ingredient folder made with --ingredient. --sidecar writes a .c2pa file beside the output, --remote embeds a URL to a manifest hosted over HTTP, and --external-manifest validates an asset against a separate .c2pa, overriding embedded and remote manifests. c2pa-rs documentation states the signed (source) asset can be output from an editing application that has not preserved the manifest store, in which case the application must extract a parent ingredient and add it to the manifest definition; hash-binding assertions (c2pa.hash.*) cannot be redacted. Failure modes. Inference from the binding model: re-encoding with a tool that does not carry or re-sign the manifest leaves a file without (or with an invalid) manifest, so keep the .c2pa sidecar or remote URL and re-sign after the final transcode, using --update or --parent to keep history. Limitations. Docs state the mechanisms; the survival behaviour per platform (social sites, ffmpeg versions) was not tested and the docs give no empirical survival rates. Prior items cover supported formats and assertion labels. Version and date. c2patool c367d9c2; c2pa-rs 8250bd96. Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Limitations: Transcode consequences are inferred from the binding model; no transcoding was executed. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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      "note": "Adding a manifest to an asset file; Update intent; Source asset versus parent asset; restrictions table"
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      "note": "Adding a manifest to an asset file; Update intent; Source asset versus parent asset; restrictions table"
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