--- title: Concepts description: The small set of primitives that make CodeSpar make sense — sessions, tools, projects, triggers, authentication. Read these once and the rest of the docs clicks into place. --- import { Callout } from "fumadocs-ui/components/callout"; # Concepts CodeSpar is built around a handful of primitives. Most of the API surface, every framework adapter, and every cookbook can be explained by reference to the concepts on this page. Read them in order the first time — you won't need to come back. --- ## Runtime primitives The objects your code holds references to. ## Tenancy & isolation How CodeSpar keeps your customers' data, credentials, and usage separate. ## Events & economics What happens after the request returns. --- ## The mental model, in one paragraph Your application holds a `CodeSpar` client. For each end user it creates a **Session** scoped to a set of servers. The session exposes 14 meta-tools (plus optional server-specific ones). When the agent calls a tool, the **Tool Router** on the CodeSpar backend picks the right provider, injects the credentials (from **Service Auth** for your own keys, or **Connect Links** for end-user OAuth), and runs the call. Successful settled transactions fire **Triggers** back to your app. **Projects** isolate one customer from another. **Billing** meters what settled. That's the whole system. Everything else is framework-specific wiring or provider-specific fields. Read the concepts in the order above the first time — each one builds on the previous. Skim back in any order after that. ## Next steps