Making stronger promise on runtime values that platform provides

Author: Luka Stojanovic

v1.0/concepts.md

@@ -281,7 +281,7 @@ be provided:
     filled in by the platform after processing the Tool but before actual
     execution.  Parameter references and expressions may only use the
     literal string value of the field and must not perform computation on
-    the contents.
+    the contents, except where noted otherwise.
 
 If the value of a field has no leading or trailing non-whitespace
 characters around a parameter reference, the effective value of the field

v1.0/invocation.md

@@ -111,6 +111,10 @@ not perform computation on the contents.
   * `runtime.outdirSize`: reserved storage space available in the designated output directory
   * `runtime.tmpdirSize`: reserved storage space available in the designated temporary directory
 
+For `cores`, `ram`, `outdirSize` and `tmpdirSize`, if an implementation can't
+provide the actual number of reserved cores during the expression evaluation time,
+it should report back the minimal requested amount.
+
 See [ResourceRequirement](#ResourceRequirement) for details on how to
 describe the hardware resources required by a tool.