Release Notes: Vector Retriever

These release notes describe the Vector Retriever microservice. For sample-application integration context, see the Video Search and Summarization release notes.

Version 2026.2.0

Release Date: August 4, 2026

New (initial release):

• Multi-backend retriever support (vdms, milvus, pgvector, faiss)

• Backend-centric folder structure under src/retriever/backends/

• Registry-based backend dispatch and filter translation

• Primary where filter grammar with compatibility aliases (tags, time_filter, filters)

• Filter capability discovery endpoint (GET /capabilities/filters)

• Batch query API with partial error handling

• Image query modality: send an image (base64 or URL) instead of text for visual similarity search, with mutually exclusive query/image fields

• Developer template and guide for adding new backends

• Docker Compose overlays for running the retriever against a selected backend

Improved:

• Hardened the VDMS over-fetch floor so fetch_k is always greater than k, improving recall when filters discard candidates.

• Backend registry, middleware, and VDMS backend fixes with expanded test coverage.

• Refreshed the OpenAPI specification.

• Resolved a copyleft licensing issue in the service dependencies.

• Documentation fixes and corrections.