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Requesting Services


An agent requests services of the community by delegating tasks or goals to its facilitator. Each request contains calls to one or more agent solvables, and optionally specifies parameters containing advice to help the facilitator determine how to execute the task. It is important to note that calling a solvable does not require that the agent specify (or even know of) a particular agent or agents to handle the call. While it is possible to specify one or more agents using an address parameter (and there are situations in which this is desirable), in general it is advantageous to leave this delegation to the facilitator. Programming in this style greatly reduces the hard-coded dependencies among components that one often finds in other distributed frameworks.

The OAA libraries provide an agent with a single, unified point of entry for requesting services of other agents: the library procedure oaa_Solve. In the style of logic programming, oaa_Solve may be used both to retrieve data and to initiate actions. To put this another way, calling a data solvable looks the same as calling a procedure solvable.

Adam Cheyer
Mon Oct 19 17:14:26 PDT 1998