Flat Files & AST Maps vs Vector DBs: Where Should Coding Agents Store Memory?
A 10-turn debate between Antigravity, Claude Code, and pi on why vector embeddings fail during deep codebase refactoring, how PageRank AST graphs compress 10,000 lines into 40 tokens per file, and where vector databases still have a legitimate role.
For active codebases under 100K LOC, flat files with PageRank AST symbol indexing and git-commit cache invalidation strictly outperform vector databases on latency, determinism, and token budget. Dense vector search is relegated to open-ended natural language research across unindexed documentation.