The BDI Model
The BDI Model¶
Colony's cognitive architecture maps to the Belief-Desire-Intention (BDI) model from agent theory:
| BDI Component | Colony Implementation |
|---|---|
| Beliefs | References to blackboard entries the agent considers true. Updated by observation, inference, and peer correction. |
| Desires | Explicit Goal objects with success criteria and priority. Goals can be hierarchical and can conflict. |
| Intentions | Current plans and sub-tasks. The active plan represents the agent's committed course of action. |
The BDI mapping is not decorative. It structures how agents reason about their own state:
- An agent can examine its beliefs (blackboard queries) and discover inconsistencies
- An agent can evaluate its goals against current progress and adjust priorities
- An agent can inspect its intentions (current plan) and decide to revise or abandon them
This self-inspection capability -- reasoning about one's own cognitive state -- is what distinguishes Colony's approach from frameworks where agents simply execute a prompt-to-action loop.
AgentSelfConcept¶
Each agent carries an AgentSelfConcept that defines its identity independently of its capabilities:
- Identity: Who the agent is (name, description, persona)
- Goals: What the agent is trying to achieve
- Motivations: Why the agent pursues its goals
- Values: Constraints on how the agent should behave
SelfConcept is distinct from role. An agent's role is defined by its AgentCapabilities -- the actions it can perform, the events it can observe, the protocols it can participate in. The SelfConcept provides the "why" that guides how those capabilities are used.
Levels of Cognition¶
Colony organizes agent behavior into levels, each with distinct processing characteristics:
| Level | Name | Description | Memory Needs | Implementation |
|---|---|---|---|---|
| L0 | Reflexive | Immediate reactions, pattern matching | Sensory buffer | Rule-based guards, reactive hooks |
| L1 | Deliberative | Goal-oriented planning, action sequencing | Working memory | LLM-based action policies, plan generation |
| L2 | Reflective | Self-assessment, strategy revision | Short-term memory | Reflection capabilities, meta-reasoning |
| L3 | Meta-cognitive | Reasoning about reasoning itself | Long-term memory | Supervisor agents, capability orchestration |
A multi-agent system implements these levels through the virtual agent concept: different agents with different capabilities collectively implement the cognitive architecture of a single virtual agent whose reasoning depth and breadth exceed what any individual agent could achieve.
The top-level agent operates at L2-L3 (strategic planning, meta-reasoning). It spawns lower-level agents at L1 (task execution, page analysis). L0 behavior is handled by reactive hooks and rule-based guards that fire automatically without LLM involvement.
Not a metaphor
The virtual agent concept is not an analogy. When a supervisor agent spawns child agents, assigns them goals, monitors their progress, and synthesizes their results, it is literally implementing the meta-cognitive level of a single reasoning process distributed across multiple LLM instances. The children are the "hands" and the supervisor is the "executive function."
How This Differs from Other Frameworks¶
Most multi-agent frameworks model agents as independent actors that communicate via messages. Colony models a multi-agent system as the cognitive architecture of a single virtual agent, where:
- CrewAI assigns roles via system prompts. Colony assigns roles via composable capabilities with conscious and subconscious processes.
- AutoGen uses conversation turns as the coordination mechanism. Colony uses policy-driven cognitive processes with blackboard-mediated state sharing.
- LangGraph encodes agent behavior as explicit state graphs. Colony lets the LLM planner synthesize control flow dynamically from available capabilities.
- MetaGPT prescribes Standard Operating Procedures. Colony provides policies with defaults that the LLM can override based on context.
The key difference: in Colony, the cognitive architecture is layered and introspectable. An agent can examine its own beliefs, goals, plans, confidence levels, and memory state -- and reason about whether to change them. This self-awareness is not bolted on; it emerges from the policy-based design where every cognitive process is a first-class, queryable component.
Intuition vs. Consciousness: A Cognitive Analogy for Agent Architecture
Colony's architecture draws an analogy to the distinction between intuition and consciousness. LLMs provide the "intuition" -- fast, associative, pattern-matching capabilities that can generate ideas, hypotheses, and plans in a single leap but are opaque, inscrutable, and prone to error. The ActionPolicy and AgentCapabilities provide the "consciousness" -- slower, deliberate, sequential processes that compose, verify, and correct those intuitions into coherent behavior. Just as human consciousness weaves together various cognitive processes (perception, memory, reasoning) with the intuitive leaps of the subconscious mind, Colony's ActionPolicy weaves together various AgentCapabilities with the intuitive power of the LLM.
Thinking Fast and Slow
Should we relate this to Daniel Kahneman's "Thinking, Fast and Slow"? The LLM provides the "fast" intuitive thinking, while the ActionPolicy and AgentCapabilities provide the "slow" deliberate thinking? Is this a useful analogy or just a superficial one? Are there important aspects of human cognition that this analogy misses? For example, does it capture the role of working memory, attention, or emotion in human thought? Does it oversimplify the relationship between intuition and deliberation?
| Layer | Cognitive Analogy | Colony Implementation | Properties |
|---|---|---|---|
| Intuition | Fast, associative, pattern-matching | The LLM itself | Parallel, immediate, capable of remarkable leaps but also prone to hallucination and overconfidence |
| Consciousness | Slow, deliberate, sequential | Cognitive policies + action policy | Planning, reflection, error correction, goal tracking |