Four vector stores, four nearly identical feature lists — ANN, filters, hybrid search, all of it. The thing that actually decides which one survives the agentic-RAG stack at scale is invisible there: where the index sits relative to your primary data.
All four ship traces, datasets, and evaluators — the feature lists nearly match. What separates them is which feedback loop they were built to close: the dev loop, CI, the production gateway, or model-monitoring drift.
Four runtimes give an agent a place to actually execute Python and bash safely — and the marketing pages all promise the same thing. The thing that decides which one survives production is who owns the sandbox lifecycle.