> Documentation index: [/llms.txt](/llms.txt). Every page as one file: [/llms-full.txt](/llms-full.txt).

# Sub-agents

Sub-agents [#sub-agents]

An agent can hand a self-contained task to another agent, a sub-agent, which works in the background and reports back in the same chat.

A coordinator such as a **Finance Team Lead** can send an invoice to the **Invoice Checker** and a claim to the **Expense Policy Advisor**, then sum up what each found. You talk to one agent; the specialists do their part.

Let an agent call other agents [#let-an-agent-call-other-agents]

Both sides need a setting in the agent editor; see [Configure an agent](/docs/platform/agents/configure).

| On the agent that delegates                               | On the agent that receives work                                |
| --------------------------------------------------------- | -------------------------------------------------------------- |
| **Sub-agents** pane: **Let this agent call other agents** | **General** pane: **Other agents can hand work to this agent** |

<img alt="The Sub-agents pane of Finance Team Lead with Let this agent call other agents on, Only selected agents chosen and three finance agents selected" src="__img0" />

With **Let this agent call other agents** on, choose which agents it can reach:

| Option                   | The agent can call                                                                                                  |
| ------------------------ | ------------------------------------------------------------------------------------------------------------------- |
| **Any callable agent**   | Every agent in the workspace that accepts work from other agents, including built-in agents added to the workspace. |
| **Only selected agents** | Only the agents you select. Saving with none selected leaves it unrestricted.                                       |

* Only agents with **Other agents can hand work to this agent** on are listed, and only published agents can be called.
* An agent without a description is marked **No description — hard to route to**: the delegating agent picks sub-agents by their description.
* Each person only gets the sub-agents they could use themselves, so the list can be shorter for them than in the editor.
* Even with no sub-agents to call, a delegating agent can split work off to two built-in helpers that use its own tools and skills.

What you see in the chat [#what-you-see-in-the-chat]

1. The agent shows a **Delegated to agent** step with the sub-agent's name and the task it sent.

   <img alt="A chat where Finance Team Lead delegated invoice 4471 to the Invoice Checker, showing the task sent and the reply that it will report back" src="__img1" />

2. While the sub-agent works, a strip above the composer shows its name, **working in the background** and the time so far. You can keep chatting.

   <img alt="The strip above the composer: Invoice Checker working in the background, See activity" src="__img2" />

3. **See activity** opens what the sub-agent is doing: its steps, the skills it reads and the tools it calls. **Stop agent** cancels it.

   <img alt="The Invoice Checker activity window, working, with a Read skill invoice-matching-rules step and a Stop agent button" src="__img3" />

4. When the sub-agent finishes, the agent you are chatting with picks up its report and answers in the chat. Files the sub-agent created appear in that answer.

   <img alt="Finance Team Lead's answer with the Invoice Checker's findings, a financial impact table and the matching report file" src="__img4" />

Rules [#rules]

| Rule                                   | Value                                                          |
| -------------------------------------- | -------------------------------------------------------------- |
| Delegation depth                       | A sub-agent can delegate once more; below that it works alone. |
| Sub-agents running at once in one chat | Up to 5                                                        |
| Files an agent can hand to a sub-agent | Up to 3, each up to 25 MB                                      |

* A sub-agent cannot ask you questions; it makes a reasonable assumption and says so in its report.
* If a sub-agent needs your approval for an action, the approval card appears in your chat.
* A sub-agent works with the files of the chat it was called from.
* A sub-agent runs its own published version, on its own model, and its usage counts toward yours. Changes in its draft reach the delegating agent only once they are published.
* While you test a draft in the editor's **Test** tab, the draft delegates, but the sub-agents it calls still run their published versions.

Sub-agents and @ mentions [#sub-agents-and--mentions]

Typing &#x2A;*@** and an agent's name sends your message to that agent yourself; the agent answers in the chat. Delegation is the agent deciding to pass work on. See [Mentions and commands](/docs/platform/chat/mentions-and-commands).