# ADR-003: Memory-Centric Architecture

## Status

Accepted

## Context

The MCP ADR Analysis Server requires persistent storage and retrieval of architectural knowledge, analysis results, and learning experiences. Based on the project analysis and memories, the system implements a sophisticated memory system with knowledge graphs, entity storage, and intelligent querying capabilities. This architecture needs to support both short-term caching and long-term knowledge retention.

## Decision

We will implement a memory-centric architecture using JSON-based storage with knowledge graph capabilities, entity relationship management, and intelligent memory retrieval systems.

Key components:

- **Knowledge Graph Storage**: Structured storage of architectural decisions and relationships
- **Entity Management**: Persistent storage of analysis entities with metadata
- **Intelligent Querying**: Context-aware memory retrieval with relevance scoring
- **Cache Infrastructure**: Multi-layer caching for performance optimization
- **Memory Integration**: Seamless integration across all MCP tools
- **Snapshot System**: Historical tracking of architectural evolution

## Consequences

**Positive:**

- Persistent knowledge retention across analysis sessions
- Intelligent context-aware retrieval of relevant past experiences
- Knowledge graph enables relationship discovery and pattern recognition
- Performance optimization through multi-layer caching
- Historical tracking enables architectural evolution analysis
- Seamless integration provides consistent memory access across tools

**Negative:**

- Increased storage requirements for comprehensive memory retention
- Complexity in managing entity relationships and knowledge graph consistency
- Potential performance impact from memory operations during analysis
- Need for sophisticated cache invalidation and consistency management
- Risk of memory corruption affecting analysis quality
- Dependency on file system reliability for persistent storage

## Related ADRs

- ADR-001: MCP Protocol Implementation Strategy (foundation)
- ADR-011: ADR Timeline Tracking and Context-Aware Analysis (extends memory concepts)
- ADR-014: CE-MCP Architecture (sandbox state management leverages memory patterns)
