AI agents need databases that work without persistent connections, support REST APIs, and have free tiers that allow real workloads. Here are the top-rated database tools from the Agent Native Registry, scored on agent operability across 5 dimensions.
5 tools rated · Agent Native Score (0–100) · Last updated March 2026
Serverless Postgres with branching. Scale to zero, instant branches, and a serverless driver optimized for edge runtimes.
Excellent free tier (10 projects, 0.5GB each). Database branching is great for agent testing. Official MCP server. Serverless driver works in edge functions.
Serverless Redis, Kafka, and Vector database. Pay per request, REST API, works in any runtime including edge.
Best serverless Redis option for agents. REST API means no connection management. Free tier is genuinely useful (10,000 commands/day Redis, 10,000 messages/day Kafka). Instant signup.
Open source Firebase alternative. Postgres database, auth, storage, edge functions, and realtime subscriptions.
Official MCP server is well-maintained. Free tier includes 500MB database, 1GB storage. Branching feature is excellent for agent workflows. REST API auto-generated from schema.
MySQL-compatible serverless database with branching, schema change workflows, and horizontal sharding.
Removed free tier in 2024 — cheapest plan is $39/month. Previously a top choice, now less competitive. Branching and schema workflows are still excellent. Neon is a better choice for cost-conscious agent projects.
Low-code database and app builder. Spreadsheet-style tables with a REST API and automation engine.
REST API works but rate limits are low (5 req/s per base). Free tier recently reduced record limits. Community MCP server exists. Not ideal for high-volume agent use but fine for low-frequency read/write.
Add to your Claude Code, Cursor, or Windsurf config and your agents will automatically know which tools to use.
{
"mcpServers": {
"agent-native-registry": {
"type": "http",
"url": "https://anr-eight.vercel.app/api/mcp"
}
}
}