# Research References

All papers, repositories, and prior art that informed this design.

---

## Core Papers

### Pichay — Demand Paging for LLM Context Windows (PRIMARY)
- **Paper:** [The Missing Memory Hierarchy: Demand Paging for LLM Context Windows](https://arxiv.org/abs/2603.09023)
- **Author:** Tony Mason (UBC / Georgia Tech)
- **Date:** March 2026, accepted ACM SIGOPS
- **Repo:** https://github.com/fsgeek/pichay (tag: v0.1.0-paper, commit b56701a)
- **Archival:** https://doi.org/10.5281/zenodo.18930122
- **Key findings:** 21.8% structural waste across 857 sessions / 4.45B tokens.
  93% context reduction in live deployment. 0.0254% fault rate over 1.4M evictions.
  Cooperative eviction via phantom tools and cleanup tags. FIFO eviction with
  pressure zones. Transparent HTTP proxy architecture.
- **Used in:** Phase 1 (fork baseline), Phase 2 (pressure zones, cleanup tags),
  Phase 3 (phantom tools)

### MemGPT / Letta — Virtual Memory for LLMs
- **Paper:** [MemGPT: Towards LLMs as Operating Systems](https://arxiv.org/abs/2310.08560)
- **Authors:** Charles Packer, Sarah Wooders, Kevin Lin, Vivian Fang, Shishir G. Patil,
  Ion Stoica, Joseph E. Gonzalez (UC Berkeley)
- **Date:** October 2023 (revised February 2024)
- **Repo:** https://github.com/letta-ai/letta (SHA: 4cb2f21c)
- **Key findings:** Three-tier memory hierarchy (core/recall/archival). Agent-initiated
  paging via tool calls. PostgreSQL + pgvector for archival storage. Partial-evict
  summarization (30% oldest messages). LLM-driven retrieval is surprisingly effective.
- **Used in:** Object Store design (SCHEMA.md), multi-fidelity concept, backing store
  architecture (Phase 3)

### xMemory — Hierarchical Structured Retrieval
- **Paper:** [Beyond RAG for Agent Memory: Retrieval by Decoupling and Aggregation](https://arxiv.org/abs/2602.02007)
- **Venue:** ICML 2026
- **Key findings:** Standard RAG on agent memory fails due to correlated content.
  Hierarchical retrieval (messages -> episodes -> semantics -> themes) prevents
  redundant retrieval. Sparsity-semantics objective for segmentation. Top-down
  retrieval reduces retrieved tokens while improving relevance.
- **Used in:** Phase 6 (xMemory hierarchy), Phase 4a (segmentation concept)

### L-RAG — Entropy-Based Lazy Context Loading
- **Paper:** [L-RAG: Balancing Context and Retrieval with Entropy-Based Lazy Loading](https://arxiv.org/abs/2601.06551)
- **Date:** January 2026
- **Key findings:** Token entropy reliably predicts model uncertainty (H=1.72 correct
  vs H=2.20 errors, p<0.001). 26% retrieval reduction at balanced threshold.
  Training-free. Works with any model.
- **Used in:** Phase 4e (entropy-gated faulting)

### A-MAC — Adaptive Memory Admission Control
- **Paper:** [Adaptive Memory Admission Control for LLM Agents](https://arxiv.org/abs/2603.04549)
- **Authors:** Workday AI
- **Date:** March 2026
- **Repo:** https://github.com/GuilinDev/Adaptive_Memory_Admission_Control_LLM_Agents
- **Key findings:** 5-factor admission scorer (Utility, Confidence, Novelty, Recency,
  TypePrior). TypePrior is most influential factor. Uses local LLM (Ollama/qwen2.5)
  for utility scoring. F1=0.583 on LoCoMo. 31% faster than LLM-native memory.
- **Used in:** Phase 4d (admission control)

---

## Supporting Papers

### Factory — Anchored Iterative Summarization
- **Source:** Factory's evaluation across 36,000 engineering sessions
- **Key findings:** Anchored summarization (persistent state with intent/changes/decisions/
  next_steps) outperforms rolling reconstruction. Scores: Factory 4.04 vs Anthropic 3.74
  vs OpenAI 3.43 on accuracy/completeness/continuity.
- **Used in:** Phase 2 (multi-fidelity compression design)

### SWE-Pruner — Neural Context Pruning for Coding
- **Authors:** Wang et al., 2026
- **Key findings:** 0.6B-parameter neural skimmer for task-aware pruning. 23-54% token
  reduction on SWE-bench. Maintains solve rates.
- **Referenced for:** Alternative approach to context reduction (learned pruning vs
  semantic objects)

### ACON — Failure-Driven Compression Optimization
- **Paper:** arXiv, October 2025
- **Key findings:** Unified history + observation compression. 26-54% peak context
  reduction. Gradient-free, works with API models. Iteratively refines compression
  prompt based on failure cases.
- **Referenced for:** Compression strategy comparison

### Neural Paging — Learned Page Controller
- **Paper:** [Neural Paging: Learning Context Management Policies for Turing-Complete Agents](https://arxiv.org/abs/2603.02228)
- **Date:** February 2026
- **Key findings:** Differentiable page controller. Semantic Belady's optimality.
  Reduces O(N^2) to O(N*K^2) complexity. Theoretical framework.
- **Referenced for:** Future work (learned eviction policy)

### CMV — DAG-Based Session History Trimming
- **Author:** Santoni, 2026
- **Key findings:** DAG-based session history structure. Structurally lossless trimming.
  Up to 86% reduction for tool-heavy sessions.
- **Referenced for:** Alternative structural approach

### MemOS — Memory Operating System for AGI
- **Authors:** Li et al., 2025
- **Key findings:** Full "Memory OS" with lifecycle control and persistent representations.
- **Referenced for:** Long-term architecture vision

### SideQuest — KV Cache Eviction via Parallel Reasoning
- **Authors:** Kariyappa & Suh, 2026
- **Key findings:** Fine-tuned parallel reasoning thread for KV cache eviction.
  56-65% peak memory reduction. Irreversible eviction.
- **Referenced for:** KV-cache-level optimization (complementary to our message-level approach)

### Quest — Query-Aware KV Cache Sparsity
- **Paper:** [Quest: Query-Aware Sparsity for Efficient Long-Context LLM Inference](https://arxiv.org/abs/2406.10774)
- **Venue:** ICML 2024, MIT Han Lab
- **Repo:** https://github.com/mit-han-lab/Quest
- **Key findings:** 2.23x self-attention speedup, 7.03x inference latency reduction.
  Query-aware page selection within KV cache.
- **Referenced for:** Within-model context selection (different layer than our system)

### SpeContext — Speculative Context Sparsity
- **Paper:** [SpeContext: Enabling Efficient Long-context Reasoning](https://arxiv.org/abs/2512.00722)
- **Authors:** SJTU / Infinigence-AI, November 2025
- **Key findings:** Small draft model predicts important KV cache tokens before main
  model runs. Analogous to speculative decoding but for context selection.
- **Referenced for:** Helper model concept (similar philosophy at different layer)

### SoK: Agentic RAG
- **Paper:** [SoK: Agentic RAG: Taxonomy, Architectures, Evaluation](https://arxiv.org/abs/2603.07379)
- **Date:** March 2026
- **Key findings:** Definitive 2026 survey. Taxonomy of planning, retrieval, memory,
  and tool coordination patterns. Identifies risks: compounding hallucination,
  memory poisoning, retrieval misalignment.
- **Referenced for:** Taxonomy and risk awareness

### Mem0 — Fact Extraction + Merge Pipeline
- **Paper:** [Mem0: Building Production-Ready AI Agents with Scalable Long-Term Memory](https://arxiv.org/abs/2504.19413)
- **Repo:** https://github.com/mem0ai/mem0 (49,561 stars)
- **Key findings:** 2-LLM-call pipeline (extract facts -> diff/merge with existing).
  +26% accuracy over OpenAI Memory on LOCOMO. 91% faster, 90% fewer tokens.
  20+ vector store backends.
- **Referenced for:** Future cross-session memory (Phase 6+)

---

## Key Repositories

### Direct Dependencies
| Repo | What We Use | Phase |
|---|---|---|
| [fsgeek/pichay](https://github.com/fsgeek/pichay) | Fork as starting point for proxy | Phase 1 |
| [pgvector/pgvector](https://github.com/pgvector/pgvector) | PostgreSQL vector similarity | Phase 3+ |
| [sentence-transformers](https://github.com/UKPLab/sentence-transformers) | all-MiniLM-L6-v2 embeddings | Phase 3+ |

### Reference Implementations
| Repo | What We Learn From | Stars |
|---|---|---|
| [letta-ai/letta](https://github.com/letta-ai/letta) | 3-tier memory architecture, archival search | 15k+ |
| [mem0ai/mem0](https://github.com/mem0ai/mem0) | Fact extraction pipeline, multi-backend vector store | 49k+ |
| [alibaizhanov/mengram](https://github.com/alibaizhanov/mengram) | 3-memory-type system (semantic/episodic/procedural) | 86 |
| [PavanVkAlapati/memory_orchestration](https://github.com/PavanVkAlapati/memory_orchestration) | Layered memory with Qdrant + Redis + MongoDB | - |
| [GuilinDev/Adaptive_Memory_Admission_Control_LLM_Agents](https://github.com/GuilinDev/Adaptive_Memory_Admission_Control_LLM_Agents) | A-MAC admission scoring | - |
| [vivek-tiwari-vt/agmem](https://github.com/vivek-tiwari-vt/agmem) | Git-like version control for agent memories | - |
| [lm-sys/RouteLLM](https://github.com/lm-sys/RouteLLM) | BERT classifier router for model selection | - |

### MCP Servers (reference for Phase 5)
| Repo | What It Does |
|---|---|
| [adamrdrew/agent-memory-mcp](https://github.com/adamrdrew/agent-memory-mcp) | Hybrid BM25 + vector search, local embeddings, 12 memory categories |
| [Parswanadh/memory-mcp-server](https://github.com/Parswanadh/memory-mcp-server) | 3-tier hierarchical memory (working/short-term/long-term) |
| [vbcherepanov/claude-total-memory](https://github.com/vbcherepanov/claude-total-memory) | 4-tier search, 20 tools, ChromaDB + SQLite |
| [van-reflect/Reflect-Memory](https://github.com/van-reflect/Reflect-Memory) | Cross-agent memory, vendor-neutral |

---

## OpenCode / Oh-My-OpenCode Integration Points

### OpenCode Plugin Hooks (from sst/opencode)
| Hook | Location | Purpose for Mnemosyne |
|---|---|---|
| `experimental.chat.messages.transform` | `packages/opencode/src/session/prompt.ts:652` | Modify message array before LLM call (context assembly) |
| `experimental.session.compacting` | `packages/opencode/src/session/compaction.ts:169` | Custom compaction prompt/context |
| `experimental.chat.system.transform` | `packages/opencode/src/session/llm.ts:84` | Modify system prompt (inject memory instructions) |
| `tool.execute.before` | `packages/plugin/src/index.ts:184` | Intercept tool args before execution |
| `tool.execute.after` | `packages/plugin/src/index.ts:192` | Process tool results for object creation |
| `chat.params` | `packages/opencode/src/session/llm.ts:114` | Modify temperature, options |

### Oh-My-OpenCode Hooks (from omc-sh/oh-my-opencode)
| Hook | Purpose for Mnemosyne |
|---|---|
| `context-window-monitor` | Existing hook -- can extend or replace |
| `preemptive-compaction` | Existing hook -- integrate with our pressure system |
| `tool-output-truncator` | Existing hook -- our fidelity system supersedes this |
| `compaction-context-injector` | Inject our memory state into compaction prompt |

---

## Benchmark Datasets

For evaluating memory quality:

| Dataset | What It Tests | URL |
|---|---|---|
| LoCoMo | Long-conversation memory (QA over multi-session chat) | https://github.com/letta-ai/letta/tree/main/tests |
| PerLTQA | Personalized long-term QA | Referenced in xMemory paper |
| SWE-bench | Coding task completion (for measuring quality impact) | https://github.com/princeton-nlp/SWE-bench |
| Terminal-Bench | CLI agent task completion | Referenced in Letta Code evaluation |

---

## Key Metrics from Literature

| System | Context Reduction | Quality Impact | Cost |
|---|---|---|---|
| Pichay (baseline eviction) | 37% token, up to 93% extreme | 0.0254% fault rate | Zero (proxy only) |
| SWE-Pruner | 23-54% | Maintains solve rates | Training cost for 0.6B model |
| ACON | 26-54% peak | 95%+ task accuracy preserved | Multiple LLM calls for training |
| Factory summarization | High | 4.04/5 accuracy score | 1 LLM call per eviction |
| Cursor lazy MCP loading | 46.9% | No degradation | Zero (lazy loading) |
| Cline file deduplication | Variable | None (lossless) | Zero (dedup only) |
| Simple observation masking | ~50% | Matches LLM summarization | Zero |
| L-RAG entropy gating | 26% retrieval reduction | Marginal impact | Logprob monitoring |
| RouteLLM model routing | 85% cost reduction | 95% quality maintained | <10ms per route |