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

# Subagents

> Context isolation by delegation: a parent hands a self-contained subtask to a child agent and gets back one concise result.

A subagent runs a self-contained subtask in an **isolated context** (a fresh
graph on a namespaced thread, with its own persona, empty message history, and a
restricted toolset) and folds back only a compact result. Subagents are defined
as single files, `packages/ziro-core/src/ziro/agents/.subagents/<id>.agent.md`, where YAML frontmatter
carries the name, model, tool surface, and scoped skills, and the Markdown body
becomes the system prompt. The `.subagents/` folder is dot-prefixed so subagents
never appear in the interactive agent picker: they are spawn-only. A child's
tool rights are the **intersection** of its own declared tools and the parent's
current rights: inherit, never widen. Eight children ship: `scout`
(source-grounded research), `solver` (drives a problem to a verified result),
`reflector` (reflection coach), `reviewer` (read-only code review), `tester`
(runs and writes tests), `doc_writer`, `fact_checker` (read plus web), and
`summarizer` (read-only).

<Note>
  This page is in progress. It will cover `subagent_policy.yaml` in full (allowed
  children, depth and spawn caps, parallel fan-out, and model failover), plus skill
  scoping and the human-in-the-loop boundary rule that a gated parent must not
  allow a shell- or write-capable child.
</Note>

<Columns cols={3}>
  <Card title="Agents" icon="boxes" href="/concepts/agents">
    The parent side of the relationship.
  </Card>

  <Card title="Tools" icon="wrench" href="/concepts/tools">
    Namespaces and the rights intersection.
  </Card>

  <Card title="Agent files" icon="folder" href="/reference/agent-files">
    The `*.agent.md` frontmatter schema.
  </Card>
</Columns>