That doesn't make sense. Annotations are specific concepts to AcroJS, you can't pass them to and from a server as if they were generic JS code blocks, nor does AcroJS support the idea of JSON.
I have html which communicate with pdf document (sendmessage html to pdf / pdf to html)
How can I send my annotation object from document pdf to html document?
I send string and it works
I don't think you can convert your document to JSON from Acrobat but there are some good open source tools out there for this
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