Where are the specifications/XSDs for Amazon MWS feed XML processing reports?

The MWS XML schemata are documented within the Selling on Amazon Guide to XML linked from the Developer Guides section in the Amazon Marketplace Web Service (Amazon MWS) Documentation.

I'm omitting a direct link to the PDF, as this might change once in a while. For the same reason the XSD files you are looking for are not publicly linked by Amazon as well, rather you'll find the links to the most current schema documents within the respective sections of the Selling on Amazon Guide to XML.

You might also be interested in the Amazon MWS Developer Guide, the Feeds API Reference and the guide for the Amazon MWS Scratchpad, which are all available there as well.

Good luck!

I know this is a rather old question but I just wanted to look at the actual XML schema files myself today.

There is an XML Documentation PDF hosted on images-na.ssl-images-amazon.com which I assume will stay there for a while. This PDF contains links to the core schema files amzn-envelope.xsd, amzn-header.xsd, and amzn-base.xsd and some other API schemas like Product.xsd which all appear to be relative to https://images-na.ssl-images-amazon.com/images/G/01/rainier/help/xsd/release_1_9/.

The PDF explicitly states that

The XSD samples shown on the Help pages may not reflect the latest XSDs. We recommend using the provided XSD links to obtain the latest [ve]rsions.

However, the official MWS Feeds API documentation also links to some XSDs but these are relative to https://images-na.ssl-images-amazon.com/images/G/01/rainier/help/xsd/release_4_1/ now, e.g. Price.xsd. Schema references also seem to be relative to this path. For example, Price.xsd includes amzn-base.xsd via <xsd:include schemaLocation="amzn-base.xsd"/> and sure enough there it is.

Unfortunately, I have no idea whether release_4_1 is the latest release of the schemas but the link from the MWS API documentation is a good indicator to me.