Upstash Redis — Serverless Cache and Queue for Agent State

Pros

• –HTTP/REST API works in edge environments (Cloudflare Workers, Vercel Edge) where TCP Redis does not
• –Per-request pricing model — zero cost at zero traffic, scales linearly
• –Global replication option reduces latency for multi-region deployments
• –QStash (message queue built on Upstash) integrates natively for reliable task queuing

Cons

• –REST API latency (~20–40ms) is 5–10× higher than TCP Redis — unsuitable for tight hot-path loops
• –Max item size 1MB per key — large agent state objects require chunking or external storage reference
• –No Lua scripting via REST API — complex atomic operations require workarounds
• –Free tier has 10k commands/day — barely adequate for testing, not production