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🧠 Cognitive Memory

Persona, Dream, Wander, Decide, Express are experimental β€” see Experimental pathways.

The Founding Distinction (MF-001)

A database returns what was written. A memory engine reconstructs what is reachable from a cue at this moment β€” under decay, association, and tier physics β€” without losing a live trace because the first index was the wrong one.

As formalized in the Memory Fundamentals Specification, the identity of a memory engine is its recall algebra, not its storage topology. Spector implements this model as a single off-heap engram substrate with multiple access paths.


The 4-Tier Memory Architecture

Rather than treating memory as an undifferentiated vector store, Spector organizes traces across four cognitive tiers to address distinct operational retention windows, access frequencies, and consolidation dynamics:

Volatile, limited-capacity buffer for the current task context. Operates as a circular buffer where the oldest entries are automatically evicted when capacity is reached.

  • Capacity: Configurable (default: 100 records)
  • Storage: In-memory segment (volatile)
  • Use case: "What was the user just talking about?"

Time-stamped event records representing autobiographical history. Partitioned by day and backed by memory-mapped files for persistence across restarts. Supports Reflect consolidation into semantic memory.

  • Capacity: Scalable via time-partitioning (benchmarked at 100k, 1M, 10M engrams; bounded recall fan-out)
  • Storage: High-performance memory-mapped partitions (persistent)
  • Use case: "What error did we debug yesterday?"

Distilled, permanent world knowledge and facts. Created by consolidation (Reflect cycles) from episodic clusters, or directly by the user. Supports two modes:

  • Partitioned Mode (default): Rolling partition files with parallel retrieval.
  • Single-File Mode: In-memory slab for light deployments.

  • Capacity: Scalable in partitioned mode (configurable per-partition, default: 10,000 records; multi-partition scaling tested to 10M)

  • Recall: Parallel scan across partitions using virtual threads
  • Compaction: Per-partition rebuilds performed live during operation
  • Use case: "The user prefers dark mode."

Learned procedures, rules, and behavioral guidelines. A small, append-only store for rules that shape the agent's reasoning.

  • Capacity: Configurable (default: 500 records)
  • Storage: In-memory segment (persistent via write-ahead log replay)
  • Use case: "Always use exponential backoff for retries."

🧭 Which Memory Tier & Pathway Do I Need?

Choosing the right memory tier ensures optimal signal-to-noise ratio, hardware cache efficiency, and retention physics. Use this interactive decision tree and comparison matrix to select the right tier and retrieval pathway for your agent:

flowchart TD
    START(["🧠 Ingesting or Recalling Knowledge"]) --> Q1{"What is the operational lifecycle of this trace?"}

    Q1 -->|"Current prompt / dialogue turn<br/>(Volatile buffer)"| T_WM["πŸ§ͺ Working Memory<br/><b>rememberWorking(...)</b><br/>β€’ Circular volatile buffer<br/>β€’ Sub-microsecond seek<br/>β€’ Auto-evicts oldest entries"]
    Q1 -->|"Timestamped event / agent action<br/>(Autobiographical journal)"| T_EM["πŸ“ Episodic Memory<br/><b>rememberEpisodic(...)</b><br/>β€’ Daily memory-mapped partition<br/>β€’ Power-law temporal decay<br/>β€’ Consolidated during sleep"]
    Q1 -->|"Distilled fact / user preference<br/>(Permanent world knowledge)"| T_SE["🧬 Semantic Memory<br/><b>rememberSemantic(...)</b><br/>β€’ Zero-GC off-heap partitions<br/>β€’ Parallel SIMD vector scan<br/>β€’ Enduring cross-session facts"]
    Q1 -->|"Operational rule / tool constraint<br/>(Behavioral guidelines)"| T_PR["βš™οΈ Procedural Memory<br/><b>rememberProcedural(...)</b><br/>β€’ Append-only WAL store<br/>β€’ Deterministic constraint check<br/>β€’ Pinned across all sessions"]

    T_WM --> P_SELECT{"How will this trace be queried?"}
    T_EM --> P_SELECT
    T_SE --> P_SELECT
    T_PR --> P_SELECT

    P_SELECT -->|"Associative cue + temporal context"| PW_FUSED["⚑ 6-Phase Fused Recall<br/>Bloom filter + valence + decay + SIMD distance"]
    P_SELECT -->|"Direct pointer / known Engram ID"| PW_DIRECT["🎯 Direct Engram Seek<br/>Zero-allocation offset seek (~150ns)"]
    P_SELECT -->|"Entity relationship or causal flow"| PW_GRAPH["πŸ•ΈοΈ Cognitive Graph Recall<br/>Hebbian association + Temporal chains"]
    P_SELECT -->|"Corroboration from multiple events"| PW_MULTI["πŸ” Multi-Evidence Recall<br/>Cross-episode fact synthesis & clustering"]

    classDef working fill:#2563eb18,stroke:#3b82f6,stroke-width:1.5px
    classDef episodic fill:#10b98118,stroke:#10b981,stroke-width:1.5px
    classDef semantic fill:#8b5cf618,stroke:#8b5cf6,stroke-width:1.5px
    classDef procedural fill:#f59e0b18,stroke:#f59e0b,stroke-width:1.5px

    class T_WM working
    class T_EM episodic
    class T_SE semantic
    class T_PR procedural

Tier Decision Matrix

Tier Substrate & Storage Retention & Eviction Latency (p50) Ingestion Verb Best-Fit Agent Scenarios
πŸ§ͺ Working Volatile off-heap circular ring FIFO eviction on capacity overflow ~100ns rememberWorking Multi-turn chat context, scratchpads, intermediate plan steps
πŸ“ Episodic Mapped binary partition files (.seg) Time-partitioned (empirically benchmarked to 10M engrams), Reflect consolidation <1ms rememberEpisodic Interaction logs, tool execution traces, temporal user events
🧬 Semantic Partitioned zero-GC off-heap slabs Permanent, compacted during offline/online cycles 1.01ms rememberSemantic User preferences, distilled facts, codebase knowledge, ontology
βš™οΈ Procedural Persistent append-only WAL segment Permanent, deterministic ordering, high salience <200ns rememberProcedural System prompt constraints, tool policies, safety guidelines

Cognitive Architecture Mapping

As established in the Memory Fundamentals Specification (MF-001), Spector models cognitive subsystems as concrete operational mechanisms addressing specific retrieval and retention requirements:

graph TB
    subgraph "🧠 Spector Memory"
        SM[SpectorMemory<br/>FaΓ§ade]:::core --> CT[RememberPathway<br/>Pathway: Remember]:::core
        SM --> RP[RecallPathway<br/>Pathway: Recall]:::core

        subgraph "Cortex β€” Tier Stores"
            NK[NamespaceKernel<br/>EngramMemory]:::core --> WM[Working<br/>Working tier]:::working
            NK --> EM[Episodic<br/>Episodic tier]:::episodic
            NK --> SE[Semantic<br/>Semantic tier]:::semantic
            NK --> PR[Procedural<br/>Procedural tier]:::procedural
        end

        subgraph "Synapse β€” Scoring"
            CS[CognitiveScorer<br/>6-phase SIMD]:::synapse --> STE[SynapticTagEncoder<br/>Bloom Filter]:::synapse
            CS --> DS[DecayStrategy<br/>Temporal Decay]:::synapse
        end

        subgraph "Neuromodulators"
            SD[SurpriseDetector<br/>Dopamine]:::synapse --> FP[FlashbulbPolicy]:::synapse
            VT[ValenceTracker<br/>Amygdala]:::synapse
            HP[HabituationPenalty<br/>Anti-filter bubble]:::synapse
            SS[SuppressionSet<br/>Inhibition]:::synapse
        end

        subgraph "3-Layer Cognitive Graph"
            HG[HebbianGraph<br/>Layer 1: Association]:::core
            TC[TemporalChain<br/>Layer 2: Causal]:::core
            HEG[HyperEntityGraph<br/>Layer 3: Event-Episode]:::core
            ED[EntityDirectory<br/>Identity Registry]:::core
            CA[CoActivationMemory<br/>STDP Learning]:::core
        end

        subgraph "Consolidation"
            RD[ReflectDaemon<br/>Reflect Consolidation]:::core
            TCC[VacuumCompactor<br/>Tombstone census only]:::core
        end

        CT --> NK
        RP --> CS
        RP --> NK
        RP --> HG
        RP --> TC
        RP --> ED
        RP --> HEG
    end

What Makes This Different

Every AI memory solution today wraps a scripting layer around Postgres/pgvector or a standard vector database. They suffer from:

  • Network latency: 50-200ms per query (HTTP β†’ DB β†’ HTTP)
  • Global Interpreter Lock: Sequential embedding and scoring under a lock
  • The truncation trap: Candidate generation by a single signal (typically cosine top-K) followed by post-filtering, permanently dropping high-importance or emotionally salient memories with lower initial cosine similarity.

Spector Memory collapses the entire cognitive stack onto a zero-overhead, off-heap memory store with hardware-accelerated scoring. The result:

Metric Traditional Python Layer Spector Memory
Query latency 50-200ms Ultra-low latency †
GC pauses Unpredictable ≀0.01% (100% off-heap) †
Scoring pipeline Post-filter (lossy) Fused SIMD (lossless)
Concurrent queries Lock-limited 61,000 QPS (Virtual Threads) †
Memory per record ~500B (Object wrappers) Compact binary header + vector

† Measured on Intel Core Ultra 9 285K, Java 25, AVX2. See Benchmarks.


Explore the Documentation

  • System Architecture


    Package hierarchy, data flow diagrams, and extensibility model

    Architecture

  • Recall Pathway & 6-Phase Scoring


    Deep dive into the SIMD hot-loop: tombstone β†’ tags β†’ valence β†’ importance β†’ L2 β†’ fused score

    Scoring Engine

  • 3-Layer Cognitive Graph


    Hebbian association, temporal causal chains, and event-episode hyperedges β€” three graph structures that augment vector recall with multi-hop reasoning, integrated with a central EntityDirectory

    Cognitive Graph

  • Cognitive Subsystems


    Principled cognitive subsystems mapped to code: Cortex, Hippocampus, Synapse, Dopamine, Amygdala, Habituation, Inhibition

    Start with Cortex

  • Performance & SIMD


    Benchmark results, SIMD kernel throughput, optimization techniques, virtual thread scaling

    Performance

  • Off-Heap Panama Design


    Zero-GC architecture, MemorySegment lifecycle, mmap partitions, 64-byte CognitiveRecord binary format

    Panama Design

  • Cognitive Evaluation


    Detailed test methodology, evaluation results, statistical comparisons, and the Mike Thompson dataset

    Evaluation & Results

  • API Reference


    SpectorMemory.Builder, RecallOptions, CognitiveResult, MemoryType β€” full method signatures

    API Reference