feat(rag): support Redis vector search as a VDBStore backend

[DavdGao]

Discussed in #2164

^{Originally posted by izualzhy July 23, 2026}

Feature Request

It would be great if AgentScope could support Redis Vector Search as a VDBStore backend.

Many users already have Redis deployed in production. Supporting Redis would allow them to build small and medium-sized RAG applications without introducing an additional vector database such as Qdrant or Milvus.

Redis Vector Search provides native support for vector indexing (HNSW/FLAT), similarity search, and metadata filtering, making it a good fit for the existing KnowledgeBase + VDBStore abstraction.

From my understanding of the current design, this could fit naturally into the existing architecture as another VDBStore implementation:

                     KnowledgeBase
                           │
                           ▼
                     VectorStoreBase
                           │
          ┌────────────────┴────────────────┐
          │                │                │
     QdrantStore          ...        RedisVectorStore (new)
                                            │
                                            ├── create collection / index
                                            ├── insert documents
                                            ├── vector search
                                            ├── delete documents
                                            ├── list documents
                                            └── (metadata_filter)

This would provide a lightweight deployment option while keeping the current architecture unchanged.

If this feature aligns with the project roadmap, I'd be happy to contribute an implementation.

[iamroylim]

I’d like to take this on. Before implementation, I’ll map the existing VDBStore contract and propose a focused Redis backend covering index creation, insert, similarity search, metadata filtering, delete, and list operations. I’ll keep Redis as an optional lazy-loaded dependency, add contract-focused tests that skip cleanly when the extra is unavailable, and update the companion docs. Please assign it to me if this scope aligns.

[xu-suping]

I'd like to give this a shot! Could it be assigned to me? @DavdGao

[izualzhy]

Hi maintainers,

Thanks for converting this discussion(#2164) into an issue.

I have read the contribution guidelines:
https://github.com/agentscope-ai/agentscope/blob/main/CONTRIBUTING_zh.md

I would like to take this issue and work on the implementation. Could you please assign it to me?

Looking forward to contributing. Thanks!