Yeah, finding SugarCRM API examples isn't an easy task. What helps me a lot is to "watch" what the SugarCRM interface does as it uses its own API. Use your browser's "Developer Tools" to capture traffic and you'll see live examples of calls. For example, clicking on a product in the catalog will give you a call like this:
Likewise, saving changes to a product will result in something like:
The request's body will be the JSON structure with the product's data. Looking at real data is better than any documentation.
I hope this helps.
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