"database" matching MCP connectors:

A portable knowledge-graph memory you pass in and get back. No database. 4 of 6 free.

AzquoA

ai.azquo

Exact, shared memory for multiple AI agents. Azquo is a hierarchical database: each fact is stored once in hierarchies that always total correctly, every write is attributed to the agent and person behind it, and any figure can be traced back to the file and cell it came from. There is no schema to design first - agents build and reorganise the structure themselves - and people work with the same data live in Microsoft Excel. Suited to finance and insurance work, where figures must stand up to review.

CWI Discovery Engine is the sync-licensing discovery layer for AI agents: natural-language brief in, licensable tracks with verified ISRCs and one-signature clearance out. 29 MCP tools (find_tracks_for_brief leads). For general ISRC metadata lookup, we defer to MusicBrainz — we are the licensable-track discovery layer, not a general database.

CobrainBOAuth

space.cobrain

Cobrain is a hosted Markdown brain your AIs share. Connect Claude, ChatGPT, Claude Code, Codex or any MCP client once (remote MCP with OAuth, no API keys to paste) and they all read and write the same notes. Share one folder with a teammate, read-only or read-write, and their AI reads it too. Permissions are enforced in the database, the same for the web app and for AIs; writes are version-checked so two AIs can't silently overwrite each other. Plain .md, exportable, EU-hosted. Free plan available.

Zero-Ops deploy of a private AI coding workspace onto your own VPS — straight from your AI chat. Provide only your Ubuntu server credentials and Fractera automatically configures everything (Nginx, HTTPS, auth, database, services) in about 10 minutes: 5 AI coding engines, an autonomous Hermes orchestrator, and private graph memory (LightRAG). No terminal, no DevOps. IP-first and free; a custom domain with HTTPS is an optional later step.

busabaseC

com.busabase

Database for your AI agent. Turn its output into data, docs, skills, and apps you can actually use.

A personal RAG database you build from chat, so AI creates work that sounds like you.

Zero-key temporary JSON database for agents: one tool call, no signup, no OAuth, no API keys.

D&D and TTRPG campaign manager for GMs: your AI reads and writes a live, typed campaign database.

AI Incident Database (AIID) MCP

Grimoire turns your TTRPG campaign into a structured, queryable database and knowledge graph and exposes it to any MCP-compatible AI client. Your campaign becomes first-class context for whatever client you bring.

Memory, reflection and safety for AI agents. Hosted or local, no vector database.

Provenance-first database for teams and agents: every value carries sources, rules and coverage.

StateyOAuth

ai.statey

An agent-native database over MCP: shared, validated, structured records in every AI chat.

Semantic search over MINDSET's brand strategy topic database, plus its system prompt.