# 🔵 Expert

**Agent rooms, transactions, checkpoints, research, and governed structural change.**

The Expert level explains how an operator can work with a live object world:
inspect it, operate within a room's authority, preserve its structure, and
reason about changes before applying them.

## What you will learn

- Read the package's architecture, component, and graph documents.
- Use capability and codegen rooms, workstations, and command surfaces.
- Follow code generation from validation to live objects.
- Check agent-supplied references and annotate registered Spells with bind hooks.
- Understand transaction admission and concurrent structural change.
- Record checkpoints, restore worlds, and integrate external storage.
- Discover named scopes through Nexus and restore their structure without restoring prior object state.
- Work with research sets, lanes, compositions, diffs, and impact views.
- Preview, stage, promote, and retire implementations deliberately.

## Choose a route

Use [Full Contents](../contents.md) to enter at a specific subject, or follow a
complete [example](../examples/index.md). Each operational lesson states its
prerequisites and the outcome it demonstrates.

[Advanced](../advanced/index.md) · [Architecture](../reference/architecture.md)


## Runnable examples

[Browse all 38 expert lessons](../examples/expert/index.md).

## Level contents

- [The runtime documents itself](self-documents.md)
- [Agent rooms and explicit authority](agent-rooms.md)
- [Build a working system from generated code](codegen.md)
- [Review agent proposals with bind hooks](bind-hooks.md)
- [Structural transactions and admission](transactions.md)
- [Persistence, profiles, and source custody](persistence.md)
- [Restore and cold boot](restore.md)
- [External storage integration](external-storage.md)
- [Research sets, lanes, residency, and recorded source](research.md)
- [Compositions, synthesis, and impact](compositions.md)
- [Preview, stage, and governed change](governed-change.md)
- [Several rooms and shared worlds](concurrency.md)
- [Complete operational walkthroughs](walkthroughs.md)


```{toctree}
:hidden:

The runtime documents itself <self-documents>
Agent rooms and explicit authority <agent-rooms>
Build a working system from generated code <codegen>
Review agent proposals with bind hooks <bind-hooks>
Structural transactions and admission <transactions>
Persistence, profiles, and source custody <persistence>
Restore and cold boot <restore>
External storage integration <external-storage>
Research sets, lanes, residency, and recorded source <research>
Compositions, synthesis, and impact <compositions>
Preview, stage, and governed change <governed-change>
Several rooms and shared worlds <concurrency>
Complete operational walkthroughs <walkthroughs>
```