Brea vs GAIA

Brea

Brea is an iMessage assistant with a free plan that needs no card, approval by reply before it sends, deletes or pays, and one-time Link cards for purchases. No outside agent can call it, paid prices sit inside the app, and no changelog or subprocessor list was found.

GAIA

GAIA's source is public, so its approval gate, memory store and token handling can be read. Three approval modes and per-tool overrides exist, but the default mode in the source runs every action unasked, which the privacy policy and release notes do not say. Pro costs $30 a month and self-hosting is limited to noncommercial use.

Brea

1. Don't plan to call Brea from another agent. It answers only the owner's iMessage thread.
2. Tell the owner that replying ALWAYS stops Brea asking again for that action.

GAIA

1. Set Settings > Approvals to Always ask or Auto before connecting mail. The default in the source runs every action, including send and delete, without asking.
2. Expect no public API on the hosted service. The backend turns off its OpenAPI document in production, so reach GAIA through its apps, bots or CLI.
3. Check the plan before relying on the hosted service. The README and docs describe a Free plan, and the pricing page says GAIA is a paid product.
4. For self-hosting, prepare Docker, Node.js 20, a WorkOS account and a model key first, and confirm the use is noncommercial under the licence.
5. Add outside tools as MCP servers by URL on the Integrations page. GAIA asks before adding a server in every approval mode.