When you call an action, the broker creates a Context instance which contains all request information and passes it to the action handler as a single argument.

Available properties & methods of Context:

Name Type Description String Context ID ServiceBroker Instance of the broker.
ctx.action Object Instance of action definition.
ctx.nodeID String Node ID.
ctx.requestID String Request ID. If you make nested-calls, it will be the same ID.
ctx.parentID String Parent context ID (in nested-calls).
ctx.params Any Request params. Second argument from
ctx.meta Any Request metadata. It will be also transferred to nested-calls.
ctx.callerNodeID String Caller Node ID if it is requested from a remote node.
ctx.level Number Request level (in nested-calls). The first level is 1. Function You can make a sub-call. Same arguments like
ctx.emit() Function Emit an event, like broker.emit
ctx.broadcast Function Broadcast an event, like broker.broadcast