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+The following are guidelines for bmcweb's use of DBus to construct Redfish
+schemas:
+
+- Do not require (ie set 500 internal error on) an implementation present a
+  property that wasn't in the first commit of the interface unless it can be
+  verified that _all_ OpenBMC implementers of the interface support that
+  property.
+- If an implementation presents a property that doesn't match the type specified
+  by the interface at any version, it shall be repored as a 500 error.
+- If the DBus interface definition has an "unknown" or "unspecified" value,
+  detecting these will omit the property from the Redfish tree, in line with the
+  Redfish specification.
+- All DBus interfaces on all object paths are optional.  An object missing an
+  interface is never an error, and shall simply omit the relevant properties
+  and/or actions from that Redfish Resource.
+- bmcweb will code to the DBus interface itself.  This means that daemons are
+  expected to handle functionally bad, but DBus-correct input in their own
+  process, and return appropriate return codes.  This is done to reduce the
+  duplication in input processing between the various user-facing daemons.
+- There are interfaces for which there is an expectation that there will only
+  ever be one producer in the project (ex bmc networking, user management).  In
+  these cases, it is desirable to call the daemon by well known name directly.
+  Bmcweb APIs should call the mapper in cases where it's reasonably expected
+  that multiple implementations exist (ex, CPU management, Sensors).