# Concepts

> The ideas LightHouse and the engine are built from, and how they fit together.

LightHouse and the engine are built from a small set of ideas. Each has a page; this one shows how they fit.

```text
 Your tenant  (https://<tenant id>.atlanticagenticlabs.com)        Atlantic's account
 ┌──────────────────────────────────────────────────────────────┐
 │ LightHouse: people, roles, keys, approvals, limits, billing  │
 │ API  ·  MCP  ·  portal                                       │
 └──────────────▲──────────────────────────────┬────────────────┘
                │ operational telemetry         │ signed commands
                │ (counts and timings)          │ (pause, approve, caps)
 ┌──────────────┴──────────────────────────────▼────────────────┐
 │ Your deployment: the Atlantic Agentic Engine                 │  Your account
 │ gateway ── models          orchestrator ── agents (cards)    │
 │ knowledge bases ── your sources     content reader           │
 └──────────────────────────────────────────────────────────────┘
```

- **[Tenants](/concepts/tenants/).** One client: its own address, its own people and keys, its data isolated by row-level security.
- **[Agents](/concepts/agents/).** An agent is a card: its job, its tools, its budget, its effect and its autonomy. Its ID is `<pack>:<card>`.
- **[Handlers](/concepts/handlers/).** The people who pause agents, set caps, grant pre-approvals and decide on outputs.
- **[Knowledge bases](/concepts/knowledge-bases/).** Your sources, indexed in your account and read in place.
- **[Evidence](/concepts/evidence/).** What an answer was grounded in, and how strong that evidence is.
- **[Approvals](/concepts/approvals/).** A person signs off an output before it counts; never an agent, never a key.
- **[Runs](/concepts/runs/).** One execution of a pack’s agents: its steps, calls, cost and outcome.
- **[The gateway](/concepts/gateway/).** The only thing that calls a model, where caps, the kill switch and the tool gate are enforced.
- **[Deployment profiles](/concepts/deployment-profiles/).** Ephemeral or always-on: whether the engine’s services sleep when nothing is asked of them.
- **[The telemetry contract](/concepts/telemetry-contract/).** What crosses from your account to LightHouse: counts and timings, never content.

Source: https://docs.atlanticagenticlabs.com/concepts/