Hermes runs Home Assistant

An evening to wire Hermes into Home Assistant, then a few weeks while it learns how your household lives.

CLI: hermes MIT · model-agnostic v0.19.0 · July 2026 219k GitHub stars

Hermes is Nous Research’s open-source agent: a terminal agent plus a gateway daemon that talks over Telegram, Discord, Signal and about twenty other platforms. Home Assistant is one of them. Hermes subscribes to state changes over HA’s WebSocket and acts with four REST tools: ha_list_entities, ha_get_state, ha_list_services and ha_call_service. The names list_entities, read_state and call_services that show up in AI answers are wrong.

That gives you judgment on fuzzy rules, which HA automations can’t do. “Lamps on around sunset, unless we’re out.” “Nudge me if the garage stays open, but not every time.” The agent watches events, keeps a small memory of the household’s patterns, and asks on Telegram before touching anything you’ve marked sensitive.

The HA add-on promises “zero to working agent in less than five minutes”; the token path took me closer to an hour. After that, give it two to three weeks before its memory is worth much. Hermes is free, but every watched event is a model turn, so route the gateway to a cheap model. The HA tools need only HASS_TOKEN.

The plan, in six parts

1What you getone evening at home: sensor events on the left, agent decisions on the right 2Product specwho it’s for, a day three weeks in, and what it won’t do 3ArchitectureWebSocket events in, four tools out, a 2,200-character memory in between 4Set it upadd-on or HASS_TOKEN, event filters, approvals, the nightly cron 5The promptsfive to paste in order, from mapping the house to letting the household check the rules 6The trapsadmin tokens, event floods that eat your model budget, the wrong lamp

Is this for you?

It’s for you if you run HA and the rules you want now are conditional and a bit vague, and you’d like Telegram nudges instead of another dashboard. Skip it if you don’t run HA yet, or if a cloud model reading your motion sensors is a dealbreaker. Voice and per-person profiles aren’t covered; profiles are in the family assistant plan.