Knowledge Interchange Format

First-order-logic-based language (Genesereth) used as a neutral content language for KQML and Ontolingua.

In this vault

Backlinks

Knowledge Representation line 8
Ontolingua line 7
Translation Approach line 7
Content Languages line 7
KQML as an Agent Communication Language line 32
Ontolingua Portable Ontology Specifications line 29
Ontolingua Portable Ontology Specifications line 21
concept-map line 25
The State of the Art in Agent Communication Languages line 35
KQML Language And Protocol line 30
KQML Overview line 35
KQML Overview line 28
Knowledge Representation Language line 8
Knowledge Sharing Effort line 7
Frame Logic line 8
KQML - A Language And Protocol For Knowledge And Information Exchange line 34
Content Language line 8

Linked Pages

Ontolingua Portable Ontology Specifications

A Translation Approach to Portable Ontology Specifications

Reference: Thomas R. Gruber (1993). Knowledge Acquisition, 5(2):199-220 (KSL Technical Report KSL-92-71). Source file: ontolingua-kaj-1993.pdf. URL

Summary

Gruber’s landmark paper defines an ontology as “an explicit specification of a conceptualization” — a formal vocabulary of classes, relations, functions, and axioms that captures the intended meaning of terms shared among knowledge-based systems. He addresses the portability problem: ontologies need to be reused across applications built in different representation languages (frame-based, description-logic, relational, Prolog), which would otherwise each need bespoke versions.

The solution is Ontolingua, a system that specifies ontologies in a standard declarative form (predicate calculus extended with KIF and frame-ontology idioms) and translates them into the forms required by specific target representation systems. The approach accommodates stylistic differences across representations while preserving declarative content, and handles translation from an expressive source into restricted targets. The paper articulates criteria for good ontology design (clarity, coherence, extendibility, minimal encoding bias, minimal ontological commitment) that still guide knowledge-engineering practice today.

Key Ideas

Ontology = explicit specification of a conceptualization.
Ontological commitments as agreements about shared vocabulary.
Translation approach: one source language → many target representations.
Ontolingua built atop KIF and a frame ontology.
Design criteria: clarity, coherence, extendibility, minimal encoding bias.

Connections

Conceptual Contribution

Claim: Shared knowledge among heterogeneous AI systems requires explicit, portable specifications of conceptualisations — ontologies — that can be defined once in a neutral declarative form and mechanically translated into many target representation systems while preserving declarative content.
Mechanism: Defines “ontology” as explicit specification of a conceptualisation; introduces ontological commitments as vocabulary-sharing agreements at the knowledge level (Newell); implements Ontolingua in KIF (Lisp-like predicate calculus with equality) with a Frame Ontology capturing class/relation/function/axiom idioms; provides translators to LOOM, Epikit, Express, and pure KIF. Proposes design criteria: clarity, coherence, extendibility, minimal encoding bias, minimal ontological commitment.
Concepts introduced/used: Ontology, Conceptualization, Ontological Commitment, KIF, Frame Ontology, Ontolingua, Knowledge-Level Specification, Translation Approach, Ontology Design Criteria
Stance: foundational / engineering
Relates to: Solves the content-language side of the problem that KQML Overview splits into content/message/communication layers; cited by virtually all agent-communication work needing shared vocabulary including FIPA-ACL, A Common Ontology Of ACLs, and Handbook On Ontologies; design criteria still guide modern ontology engineering.

KQML - A Language and Protocol for Knowledge and Information Exchange

Reference: Finin, Fritzson, McKay, McEntire (1994). AAAI Technical Report WS-94-02 (ARPA Knowledge Sharing Effort). Source file: 741.pdf. URL

Summary

This paper describes the design of the Knowledge Query and Manipulation Language (KQML), an agent communication language developed under the ARPA Knowledge Sharing Effort. KQML is both a message format and a message-handling protocol supporting run-time knowledge sharing among cooperating intelligent agents. Its core contribution is an extensible set of performatives (speech-act-style operations such as tell, ask-if, ask-all, subscribe, advertise, broker, recruit) that define what an agent may do with another agent’s knowledge and goal stores.

KQML is organised as three layers - content, message, and communication - where the message layer carries a performative and metadata while the content layer is treated as opaque (often KIF). The paper introduces facilitators - special agents that coordinate others via content-based routing, brokering, recruiting, and matchmaking - and describes KRILs (KQML Router Interface Libraries) for embedding KQML into Lisp, Prolog, C, and SQL applications.

Key Ideas

Performative-based messaging grounded in speech act theory.
Three-layer architecture: content, message, communication.
Facilitators for content-based routing, brokering, recruiting.
KRILs as embedding libraries for existing systems.
Prototype uses: ARPA Rome Planning Initiative, CAD/CAM, intelligent databases.

Connections

Conceptual Contribution

Claim: Knowledge sharing among heterogeneous intelligent agents is best realised by a layered, performative-based message protocol whose content is opaque and whose routing is mediated by special facilitator agents.
Mechanism: Defines a three-layer architecture (content / message / communication), a set of extensible performatives grounded in Speech Act Theory, facilitators for brokering/recruiting/matchmaking, and KRIL embedding libraries for Lisp/Prolog/C/SQL.
Concepts introduced/used: KQML, Performatives, Facilitators, Content Languages, KIF, Speech Act Theory, Ontologies, Multi-Agent Systems, Agent Communication Languages
Stance: foundational / engineering
Relates to: Direct philosophical descendant of Foundations Of Illocutionary Logic and sibling proposal to Common Business Communication Language; becomes the ancestor that FIPA-ACL, Agent Communication And Institutional Reality, A Common Ontology Of ACLs, and the modern surveys (Survey Of AI Agent Protocols, Survey Of Agent Interoperability Protocols) all build on or critique.

An Overview of KQML: A Knowledge Query and Manipulation Language

Reference: KQML Advisory Group — Tim Finin, Don McKay, Rich Fritzson (and Hans Chalupsky, Stuart Shapiro, Gio Wiederhold) (1992/1993). Technical report, DARPA Knowledge Sharing Effort. Source file: kqmloverview.pdf. URL

Summary

This foundational technical report introduces KQML, the language and protocol designed under the DARPA-sponsored Knowledge Sharing Effort to enable interoperability among heterogeneous intelligent agents and knowledge-based systems. It identifies the canonical module types — End User Applications (EUAs), Knowledge-Based Systems (KBs), Knowledge Base Repositories (KBRs), Databases (DBs), and Active Sensors (ASs) — and enumerates the fifteen possible interfaces between them, selecting KB-to-KB knowledge interchange as the central target.

KQML is organized as three layers: a content layer (domain content in KIF or other logic), a message layer (performatives like tell, ask-one, subscribe, advertise, register), and a communication layer (sender, receiver, reply-ids, transport). The report details performatives, facilitators/routers (SKTP), ontology/topic matching, and a Prolog-based implementation. It set the vocabulary and architectural template for nearly all subsequent agent-communication work.

Key Ideas

Three-layer design: content, message, communication.
Performatives as named speech-act-like primitives (tell, ask, subscribe, advertise).
Facilitators/mediators (SKTP) for routing and knowledge-based-service discovery.
Module taxonomy: EUA, KB, KBR, DB, AS.
Separation of content language (KIF) from communication language (KQML).

Connections

KQML
FIPA-ACL
Agent Communication Languages
Ontologies
Speech Act Theory
Performatives
Facilitators
KQML Language And Protocol — journal companion
KQML as an Agent Communication Language — tutorial companion
KQML - A Language And Protocol For Knowledge And Information Exchange — 1994 workshop original
KIF
Mentalistic Semantics
Conceptualization

Conceptual Contribution

Claim: Large heterogeneous knowledge-based systems need a standard high-level language and protocol for interchange that separates domain content (ontologies/KIF) from communicative intent (performatives) and from transport — KQML provides this missing middle layer.
Mechanism: Defines module taxonomy (EUA, KB, KBR, DB, AS) and their 15 interfaces; proposes KQML’s three-layer architecture (content / message / communication); specifies performatives (tell, ask-one/all, stream, subscribe, advertise, register, broker, recruit, recommend) inspired by speech acts; specifies SKTP (facilitator) protocol for routing, ontology matching, and service discovery; gives a Prolog reference implementation.
Concepts introduced/used: KQML, Performatives, Facilitator, SKTP, Content Language, KIF, Knowledge Sharing Effort, Ontology Matching, Speech Acts
Stance: engineering / foundational
Relates to: The language critiqued in ACL Rethinking Principles and Verifiable Semantics for ACLs for its mentalistic informal semantics; its performatives are inherited by FIPA-ACL and the conversation work in Coordinating Agents Using ACL Conversations; its ontology-sharing aspirations are addressed by Ontolingua Portable Ontology Specifications.