Home › Architecture › 4-Layer Context Schema

4-Layer Enterprise Context Schema

The 4-Layer Enterprise Context Schema is an Engram-original architecture pattern designed to solve the fundamental problem of stateless AI.

Overview

Every interaction in Engram flows through a structured context object with four layers:

Layer Question System Component
Layer 1: Security WHO is making the request? WHAT can they access? Azure Entra ID + RBAC
Layer 2: Episodic WHAT happened recently in this conversation? Rolling window + summary
Layer 3: Semantic WHAT do we know from long-term memory? Zep knowledge graph
Layer 4: Operational WHAT are we doing right now? Temporal workflow state

Documentation

Layer Details

Layer 1: SecurityContext

Identity & Permissions

  • user_id, tenant_id, session_id
  • roles, scopes
  • email, display_name

Why: Multi-tenancy, RBAC enforcement, audit trail

Layer 2: EpisodicState

Short-Term Working Memory

  • Rolling window of recent turns
  • Compressed narrative of history
  • Prevents “Lost in the Middle”

Why: Continuity, context window management

Layer 3: SemanticKnowledge

Long-Term Memory Pointers

  • Facts from knowledge graph
  • Entity context and relationships
  • Relevance scoring

Why: Long-term memory, provenance, relevance

Layer 4: OperationalState

Workflow & Execution State

  • Temporal workflow IDs
  • Plan steps and tool state
  • Human-in-the-loop support
  • Cost tracking

Why: Durable execution, cost tracking, resumability

Enterprise Security

The SecurityContext (Layer 1) is the foundation of enterprise security:

  • ✅ Consistent Identity: Same user_id across all systems
  • ✅ Enterprise Boundaries: Tenant isolation, project scoping
  • ✅ Agent Attribution: Marcus’s work is attributable to him
  • ✅ Access Control: Employees only see their current project data

See: Security Context Architecture

Related: Brain + Spine, Authentication