Summary

Add explicit MongoDBConfig interface to DatabaseConfig type to give MongoDB first-class typing parity with Pinecone, PgVector, and Chroma in RAG configuration.

Problem

Currently, MongoDB is supported for RAG/vector operations but lacks dedicated typing in the DatabaseConfig type definition. The type at packages/rag/src/tools/types.ts#L78-L83 has explicit keys for:

• pinecone: PineconeConfig
• pgvector: PgVectorConfig
• chroma: ChromaConfig

But MongoDB has no corresponding mongodb: MongoDBConfig key. This makes MongoDB:

• Less discoverable (doesn't appear in IDE autocomplete)
• Harder to configure correctly (no type hints)
• Perceived as second-class compared to other vector stores

Acceptance Criteria

• TBD
• Update Mastra documentation to reflect this change

Implementation Notes

File to modify: packages/rag/src/tools/types.ts

Reference implementations: Look at PineconeConfig, PgVectorConfig, ChromaConfig for structure and patterns