AgentDB Advanced Features

Enable QUIC sync by setting enableQUICSync to true in createAgentDBAdapter, then specify syncPort and syncPeers with peer addresses. Alternatively, set the AGENTDB_QUIC_SYNC, AGENTDB_QUIC_PORT, and AGENTDB_QUIC_PEERS environment variables before starting each node.

Use retrieveWithReasoning with a filters object supporting operators like $gte, $lte, $in, and $contains alongside the query embedding. You can also set hybridWeights to balance vector similarity against metadata match scores.

Cosine similarity works best for normalized text embeddings and semantic search, Euclidean distance suits spatial data and image embeddings, and dot product is fastest for pre-normalized vectors. Choose based on whether vector magnitude matters for your data.

QUIC sync commonly fails when the firewall blocks UDP traffic on port 4433, so allow it with a rule like ufw allow 4433/udp. Verify peers are reachable via ping and enable debug logging with DEBUG=agentdb:quic to diagnose further.

MMR (Maximal Marginal Relevance) diversifies retrieved results to reduce redundancy among similar matches. The mmrLambda parameter controls the trade-off: 0 maximizes relevance, 1 maximizes diversity, and 0.5 provides a balanced default.