Quick context: I'm currently working on a multidatabase data agent (PostgreSQL + MongoDB + DuckDB) for the DataAgentBench benchmark, so I scanned your list through that lens.

Two things that stood out:

• Seeing genai-toolbox (Google MCP Toolbox) listed we're using this as our standard interface layer and it's been solid for abstracting query dialects across DB types.

• The RAG section has good coverage, but I'd love to see more tools focused on evaluation of RAG/agent pipelines (e.g., tools that trace tool calls, score pass@1 against held-out queries, or detect silent join failures). We built a lightweight harness using the Sentinel pattern from a prior project, but curious if others have open-sourced something more general.

One question for you / the community:

Have you come across any OSS tools that specifically help with ill-formatted join key resolution across heterogeneous databases? (e.g., auto-detecting that customer_id = 12345 in PostgreSQL should match "CUST-00123" in MongoDB). This is a huge pain point in enterprise data work and most benchmarks gloss over it but it's where agents silently fail in production.

Suggestion for the repo:

Consider adding a small "Evaluation & Testing" category. Tools like:

DataAgentBench (arxiv.org/html/2603.20576) benchmark for realistic multiDB agent workloads

promptfoo or langsmith for trace-based evaluation

Simple harness templates that output {answer, query_trace, confidence}

Happy to PR a few additions if helpful. Also, if anyone's working on multidatabase agent tooling and wants to compare notes on failure modes, I'm around.