Hermes is the only one of the six that is not primarily a coding agent. It is a personal agent: Home Assistant, Spotify, Google Meet, image and video generation, TTS and wake words, a kanban board, a cron scheduler — alongside file editing, a persistent shell and three browser backends. Its 104 built-in tools are sliced into ~60 named toolsets so each surface presents a different, narrower schema.
The architectural centrepiece is a real learning loop. Every tenth turn, a forked AIAgent runs on a daemon thread, inherits the parent's exact runtime so it reuses the same prompt cache, is restricted at dispatch level to memory and skill tools, auto-denies dangerous commands, and asks itself whether anything should be written down. A separate curator then acts as librarian — consolidating, pinning and archiving skills, never deleting.
Memory is deliberately unfashionable: two markdown files with a § delimiter and character budgets, edited by substring match, injected wholesale as a frozen snapshot at session start. No vectors, no embeddings. The searchable half of memory is a SQLite/FTS5 conversation store; the procedural half is the skill library. Vector backends exist only as swappable plugins, capped at one at a time.
And the surface layer is as large as the agent itself. A single gateway process runs 31 chat platforms — Telegram, Discord, Slack, WhatsApp, Signal, Matrix, email, SMS and more — with turn leases, a delivery ledger, drain control and scale-to-zero. It is closer to a message-broker runtime than a chat REPL.