> ## Documentation Index
> Fetch the complete documentation index at: https://docs.9thprotocol.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Sub-agents

> Parallel agents with their own context for search and unattended work.

9p can spawn sub-agents through its `task` tool. Each gets a **fresh context
window**, does its job, and returns only its findings, which is the point: a
wide search doesn't fill the main conversation with file dumps.

## Two kinds

| Type      | Tools                              | Typical use                    |
| --------- | ---------------------------------- | ------------------------------ |
| `explore` | read-only (`read`, `glob`, `grep`) | "find everywhere we do X"      |
| `general` | all tools                          | a self-contained chunk of work |

## Parallelism

Multiple `task` calls issued in one response run **concurrently**. Asking a
question that spans several subsystems usually produces several explorers at
once, then a single synthesis.

```
⚙ task(explore): auth middleware
⚙ task(explore): session storage
⚙ task(explore): token refresh paths
```

## Cost

Sub-agent usage rolls up into your session totals, and spend rows are tagged so
the [dashboard](/credits) can separate main-loop cost from fan-out cost.

Explore agents are always routed to **economy models**, whatever the parent is
using. Three parallel explorers on a frontier model would cost more than the
answer is worth.

## Limits

* **Depth cap of 2**: a sub-agent's sub-agent cannot spawn further.
* **Spawning is permission-gated**, since a sub-agent runs unattended.
* Sub-agents run in `bypass` mode internally; the gate was the spawn itself, and
  `explore` agents have no write tools regardless.

## Getting good results

A sub-agent cannot see your conversation. Its prompt must be self-contained and
say what to return:

<CodeGroup>
  ```text Good theme={null}
  Search the repo for every place we construct a JWT. For each, return
  file:line, which library is used, and whether an expiry is set.
  ```

  ```text Bad theme={null}
  Look into the auth thing we discussed and report back.
  ```
</CodeGroup>

You rarely invoke sub-agents directly, 9p decides when a task is wide enough to
fan out. Asking for something explicitly broad ("check the whole codebase for…")
is what tends to trigger it.