This code system http://hl7.org/fhir/contract-action defines the following codes:

CodeDisplayDefinition
action-a Action ADefinition for Action A
action-b Action BDefinition for Action B
<status value="draft"/><experimental value="false"/><description value="This value set includes sample Contract Action codes."/><copyright value="This is an example set."/><caseSensitive value="true"/><content value="complete"/><concept><code value="action-a"/><display value="Action A"/><definition value="Definition for Action A"/></concept><concept><code value="action-b"/><display value="Action B"/><definition value="Definition for Action B"/></concept></CodeSystem>