Is there any policy or process in AMT that would prevent an ExternalQuestion from requesting that the worker download an application to perform their task on? i.e. a desktop application rather than a web application? The assignments and so on could be handled from the API as far as I can tell.
The answer to this question is "yes, kinda". While the policy itself doesn't explicitly prohibit it, the FAQ gives this as an example of a question that will be rejected. I contacted the AMT team, and they confirmed verbally that it's prohibited.