Minimum
512MB RAM can work for a simple bot; 1GB RAM is a safer baseline.
A small bot does not need a big server. The useful baseline is a cheap 1GB VPS with reliable restarts, clean logs, HTTPS if you use webhooks, and enough headroom for a small database.
512MB RAM can work for a simple bot; 1GB RAM is a safer baseline.
1 vCPU / 1GB RAM / 20GB+ SSD for a bot plus logs and updates.
Upgrade when the bot adds queues, databases, image work, or many concurrent users.
Bots are usually light until they add media processing, queues, databases, or many users. The boring parts matter most: process restarts, logging, API limits, and a provider region close enough for responsive commands.
Use 1GB RAM for a real bot. Use 512MB only for a simple hobby bot that you can redeploy quickly.