FIPA Query Ref Communicative Act Specification


Document title

FIPA Query Ref Communicative Act Specification

Document number


Document source


Document status


Date of this status





Change history


Deprecated by FIPA00037


Line numbering added











2000 Foundation for Intelligent Physical Agents -

Geneva, Switzerland


Use of the technologies described in this specification may infringe patents, copyrights or other intellectual property rights of FIPA Members and non-members. Nothing in this specification should be construed as granting permission to use any of the technologies described. Anyone planning to make use of technology covered by the intellectual property rights of others should first obtain permission from the holder(s) of the rights. FIPA strongly encourages anyone implementing any part of this specification to determine first whether part(s) sought to be implemented are covered by the intellectual property of others, and, if so, to obtain appropriate licenses or other permission from the holder(s) of such intellectual property prior to implementation. This specification is subject to change without notice. Neither FIPA nor any of its Members accept any responsibility whatsoever for damages or liability, direct or consequential, which may result from the use of this specification.


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1 Scope. 3

2 Query Ref3

3 References. 3

1         Scope

This document specifies the Query Ref communicative act that is compliant to [FIPA00037] requirements.


2         Query Ref


The action of asking another agent for the object referred to by an referential expression.


A descriptor (a referential expression).


Query-ref is the act of asking another agent to inform the requestor of the object identified by a descriptor. The sending agent is requesting the receiver to perform an inform act (see [FIPA00046]), containing the object that corresponds to the descriptor.


The agent performing the query-ref act:


         does not know which object or set of objects corresponds to the descriptor, and,


         believes that the other agent does know which object or set of objects corresponds to the descriptor.

Formal Model

<i, query-ref(j, Ref x d(x))

<i, request(j, <j, inform-ref(i, Ref x d(x))>)>

FP: Brefi(Ref x d(x))Urefi(Ref x d(x))

Bi Ij Done(<j, inform-ref(i, Ref x d(x))>)

RE: Done(<i, Inform(j, Ref x d(x) = r1)>|...|

<i, Inform(j, Ref x d(x) = rk)>)


Note: Ref xd(x) is one of the referential expressions: ix d(x), any x d(x) or all x d(x).


Agent i asks agent j for its available services:



:sender i

:receiver j


(all ?x

(available-services j ?x))



j replies that it can reserve trains, planes and automobiles:



:sender j

:receiver i



(all ?x

(available-services j ?x))

(set (reserve-ticket train)

(reserve-ticket plane)

(reserve automobile)))


3         References

[FIPA00037] FIPA Communicative Act Library Specification. Foundation for Intelligent Physical Agents, 2000.

[FIPA00046] FIPA Inform Communicative Act Specification. Foundation for Intelligent Physical Agents, 2000.