BDI Mental State Modeling
Transform external RDF context into agent mental states (beliefs, desires, intentions) using formal BDI ontology patterns. This skill enables agents to reason about context through cognitive architecture, supporting deliberative reasoning, explainability, and semantic interoperability within multi-agent systems.
When to Activate
Activate this skill when:
- Processing external RDF context into agent beliefs about world states
- Modeling rational agency with perception, deliberation, and action cycles
- Enabling explainability through traceable reasoning chains
- Implementing BDI frameworks (SEMAS, JADE, JADEX)
- Augmenting LLMs with formal cognitive structures (Logic Augmented Generation)
- Coordinating mental states across multi-agent platforms
- Tracking temporal evolution of beliefs, desires, and intentions
- Linking motivational states to action plans
Do not activate this skill for adjacent work owned by other skills:
- General context-window explanations or attention mechanics:
context-fundamentals. - Persistent user, entity, or conversation memory without formal BDI state:
memory-systems. - Supervisor, swarm, or handoff topology decisions:
multi-agent-patterns. - General agent evaluation rubrics or quality gates:
evaluation.
Core Concepts
Mental Reality Architecture
Separate mental states into two ontological categories because BDI reasoning requires distinguishing what persists from what happens:
Mental States (Endurants) -- model these as persistent cognitive attributes that hold over time intervals:
Belief: Represent what the agent holds true about the world. Ground every belief in a world state reference.Desire: Represent what the agent wishes to bring about. Link each desire back to the beliefs that motivate it.Intention: Represent what the agent commits to achieving. An intention must fulfil a desire and specify a plan.
Mental Processes (Perdurants) -- model these as events that create or modify mental states, because tracking causal transitions enables explainability:
BeliefProcess: Triggers belief formation/update from perception. Always connect to a generating world state.DesireProcess: Generates desires from existing beliefs. Preserves the motivational chain.IntentionProcess: Commits to selected desires as actionable intentions.
Cognitive Chain Pattern
Wire beliefs, desires, and intentions into directed chains using bidirectional properties (motivates/isMotivatedBy, fulfils/isFulfilledBy) because this enables both forward reasoning (what should the agent do?) and backward tracing (why did the agent act?):
:Belief_store_open a bdi:Belief ;
rdfs:comment "Store is open" ;
bdi:motivates :Desire_buy_groceries .
:Desire_buy_groceries a bdi:Desire ;
rdfs:comment "I desire to buy groceries" ;
bdi:isMotivatedBy :Belief_store_open .
:Intention_go_shopping a bdi:Intention ;
rdfs:comment "I will buy groceries" ;
bdi:fulfils :Desire_buy_groceries ;
bdi:isSupportedBy :Belief_store_open ;
bdi:specifies :Plan_shopping .
World State Grounding
Always ground mental states in world state references rather than free-text descriptions, because ungrounded beliefs break semantic querying and cross-agent interoperability:
:Agent_A a bdi:Agent ;
bdi:perceives :WorldState_WS1 ;
bdi:hasMentalState :Belief_B1 .
:WorldState_WS1 a bdi:WorldState ;
rdfs:comment "Meeting scheduled at 10am in Room 5" ;
bdi:atTime :TimeInstant_10am .
:Belief_B1 a bdi:Belief ;
bdi:refersTo :WorldState_WS1 .
Goal-Directed Planning
Connect intentions to plans via bdi:specifies, and decompose plans into ordered task sequences using bdi:precedes, because this separation allows plan reuse across different intentions while keeping execution order explicit:
:Intention_I1 bdi:specifies :Plan_P1 .
:Plan_P1 a bdi:Plan ;
bdi:addresses :Goal_G1 ;
bdi:beginsWith :Task_T1 ;
bdi:endsWith :Task_T3 .
:Task_T1 bdi:precedes :Task_T2 .
:Task_T2 bdi:precedes :Task_T3 .
T2B2T Paradigm
Implement Triples-to-Beliefs-to-Triples as a bidirectional pipeline because agents must both consume external RDF context and produce new RDF assertions. Structure every T2B2T implementation in two explicit phases:
Phase 1: Triples-to-Beliefs -- Translate incoming RDF triples into belief instances. Use bdi:triggers to connect the external world state to a BeliefProcess, and bdi:generates to produce the resulting belief. This preserves provenance from source data through to internal cognition:
:WorldState_notification a bdi:WorldState ;
rdfs:comment "Push notification: Payment request $250" ;
bdi:triggers :BeliefProcess_BP1 .
:BeliefProcess_BP1 a bdi:BeliefProcess ;
bdi:generates :Belief_payment_request .
Phase 2: Beliefs-to-Triples -- After BDI deliberation selects an intention and executes a plan, project the results back into RDF using bdi:bringsAbout. This closes the loop so downstream systems can consume agent outputs as standard linked data:
:Intention_pay a bdi:Intention ;
bdi:specifies :Plan_payment .
:PlanExecution_PE1 a bdi:PlanExecution ;
bdi:satisfies :Plan_payment ;
bdi:bringsAbout :WorldState_payment_complete .
Notation Selection by Level
Choose notation based on the C4 abstraction level being modeled, because mixing notations at the wrong level obscures rather than clarifies the cognitive architecture:
| C4 Level | Notation | Mental State Representation |
|---|---|---|
| L1 Context | ArchiMate | Agent boundaries, external perception sources |
| L2 Container | ArchiMate | BDI reasoning engine, belief store, plan executor |
| L3 Component | UML | Mental state managers, process handlers |
| L4 Code | UML/RDF | Belief/Desire/Intention classes, ontology instances |
Justification and Explainability
Attach bdi:Justification instances to every mental entity using bdi:isJustifiedBy, because unjustified mental states make agent reasoning opaque and untraceable. Each justification should capture the evidence or rule that produced the mental state:
:Belief_B1 a bdi:Belief ;
bdi:isJustifiedBy :Justification_J1 .
:Justification_J1 a bdi:Justification ;
rdfs:comment "Official announcement received via email" .
:Intention_I1 a bdi:Intention ;
bdi:isJustifiedBy :Justification_J2 .
:Justification_J2 a bdi:Justification ;
rdfs:comment "Location precondition satisfied" .
Temporal Dimensions
Assign validity intervals to every mental state using bdi:hasValidity with TimeInterval instances, because beliefs without temporal bounds cannot be garbage-collected or conflict-checked during diachronic reasoning:
:Belief_B1 a bdi:Belief ;
bdi:hasValidity :TimeInterval_TI1 .
:TimeInterval_TI1 a bdi:TimeInterval ;
bdi:hasStartTime :TimeInstant_9am ;
bdi:hasEndTime :TimeInstant_11am .
Query mental states active at a specific moment using SPARQL temporal filters. Use this pattern to resolve conflicts when multiple beliefs about the same world state overlap in time:
SELECT ?mentalState WHERE {
?mentalState bdi:hasValidity ?interval .
?interval bdi:hasStartTime ?start ;
bdi:hasEndTime ?end .
FILTER(?start <= "2025-01-04T10:00:00"^^xsd:dateTime &&
?end >= "2025-01-04T10:00:00"^^xsd:dateTime)
}
Compositional Mental Entities
Decompose complex beliefs into constituent parts using bdi:hasPart relations, because monolithic beliefs force full replacement on partial updates. Structure composite beliefs so that each sub-belief can be independently updated, queried, or invalidated:
:Belief_meeting a bdi:Belief ;
rdfs:comment "Meeting at 10am in Room 5" ;
bdi:hasPart :Belief_meeting_time , :Belief_meeting_location .
# Update only location componen