> ## Documentation Index
> Fetch the complete documentation index at: https://docs.usefused.com/llms.txt
> Use this file to discover all available pages before exploring further.

# SubAgents

> Choose flat, folder-owned, portable, or native SubAgent composition.

SubAgents use the same managed `Agent` definition as the root. Their location defines ownership and capability access.

| Shape                 | Use it when                                                    | Private capabilities |
| --------------------- | -------------------------------------------------------------- | -------------------: |
| Flat SubAgent         | The agent needs only a definition                              |                   No |
| Folder-owned SubAgent | The agent owns instructions, tools, MCP, skills, or sandboxing |                  Yes |
| Portable graph node   | The multi-agent flow must move between frameworks              | Defined by the graph |
| Advanced SubAgent     | The child requires a native framework target                   |      Framework-owned |

<CardGroup cols={2}>
  <Card title="Flat SubAgents" icon="file" href="/harnest/build/subagents/flat-subagents">
    Add a small SubAgent definition with no private bundle.
  </Card>

  <Card title="Folder-owned SubAgents" icon="folder" href="/harnest/build/subagents/folder-subagents">
    Give a SubAgent its own instructions and capabilities.
  </Card>

  <Card title="Framework behavior" icon="code-branch" href="/harnest/build/subagents/framework-behavior">
    Choose portable graph composition or a framework-specific child.
  </Card>

  <Card title="Agents and graphs" icon="diagram-project" href="/harnest/build/agents-and-graphs">
    Compose SubAgents into deterministic portable flows.
  </Card>
</CardGroup>

## Ownership rule

Parent capabilities do not flow into a child automatically. Child capabilities do not leak back to the parent. The filesystem location is the access boundary.