Conversion Receipt Builder

Binds one file-conversion event into a canonical receipt tying the input digest to the converter identity, the parameters, and the output digest. binding_sha256 is SHA-256 over the JCS-canonical receipt with binding_sha256 removed. Any external converter, including the heavy WASM Conversion Lab tools, can feed it digests, and it is the documented hand-off point for BrowserChain anchoring. This binds a transformation edge between two digests, which is a different job from anchor_document_integrity (art-121, existence and timestamp of one document). Returns the receipt plus checks for hex validity, converter identity completeness, and self-conversion. Zero network, zero PII.

Tool URL: https://ainumbers.co/chaingraph/art-191-conversion-receipt-builder.html