The Minimum Information about a Biosynthetic Gene cluster (MIBiG) specification provides a robust community standard for annotations and metadata on biosynthetic gene clusters and their molecular products.
MIBiG is a Genomic Standards Consortium project that builds on the Minimum Information about any Sequence (MIxS) framework.

MIBiG will facilitate the standardized deposition and retrieval of biosynthetic gene cluster data as well as the development of comprehensive comparative analysis tools. It will empower next-generation research on the biosynthesis, chemistry and ecology of broad classes of societally relevant bioactive secondary metabolites, guided by robust experimental evidence and rich metadata components.

The JSON specifications of the MIBiG schema and options are freely available for download and can be used to validate MIBiG data from other sources.
Also, a tarball with all MIBiG entries in raw JSON format is available for download.

To get an idea of what kind of information is included in MIBiG entries, please have a look at the visualized entries for erythromycin, actinorhodin, calcium-dependent antibiotic, microbisporicin and marneral. They can be downloaded in JSON format by clicking the corresponding button (down-pointing arrow) at the top right of their page.

Here you can find a Standard Operating Procedure (published in Standards in Genomic Sciences), which provides a detailed workflow/tutorial on submitting an entry to MIBiG. This includes a video tutorial, which explains the procedure in detail.