Re: [webpayments] How are payment instruments registered? (#14)

I have a preference for considering [The Rule of Least Power](http://www.w3.org/2001/tag/doc/leastPower.html) here. What that means to me is that payment instruments should either be data-only or their self-description (in manifest form for example) must provide enough information for user agents to retrieve and automatically install the software necessary to make use of them from the Web.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webpayments/issues/14#issuecomment-161660985