- Fix Anthropic cache token cost formula: input_tokens, cache_read, and
cache_write are all separate (not overlapping), so don't subtract
cache_write from input_tokens
- Default memory user ID to "default" when x-headroom-user-id header is
not provided, removing the need for client configuration
- Update CLI help text and tests to reflect new default behavior
Implement comprehensive memory system supporting:
- Local backend (SQLite + FTS5 + HNSW) for zero-dependency operation
- Mem0 backends (Neo4j + Qdrant) for production graph memory
- DirectMem0Adapter for optimized pre-extracted data (bypasses LLM)
- Memory extraction with facts, entities, and relationships
- Proxy integration with --memory flag for automatic memory injection
Key components:
- headroom/memory/backends/: LocalBackend, Mem0Backend, DirectMem0Adapter
- headroom/memory/system.py: MemorySystem with tool-based interface
- headroom/memory/extraction.py: Entity and relationship extraction
- headroom/proxy/memory_handler.py: Proxy integration layer
- headroom/prediction/feature_extractor.py: Content analysis features
Testing:
- 217 new memory system tests covering all backends
- LoCoMo evaluation framework for memory quality assessment
- Integration tests for proxy memory functionality
Also removes deprecated example files in favor of focused test coverage.
