# SubAgentCallMode

> Tracon documentation. Tracon is a .NET package family that adds a control
> plane on Microsoft Agent Framework, published as NuGet packages that run
> inside your own ASP.NET Core application.
>
> Page: https://tracon.dev/api/tracon.subagentcallmode/
> Summary: SubAgentCallMode: How an agent calls the agents it may call (CallableAgents).

<div class="api-provenance">Namespace Tracon · Assembly <code>Tracon.Abstractions.dll</code></div>

How an agent calls the agents it may call (`CallableAgents`).

```csharp
[JsonConverter(typeof(JsonStringEnumConverter<SubAgentCallMode>))]
public enum SubAgentCallMode
```

## Fields

`Background = 0` 

The agent starts a background task, waits for it and reads its result with the Microsoft
Agent Framework task tools. Several sub-agents run in parallel. The default.

`Tool = 1` 

Each callable agent is one tool, named after the agent. One call runs the sub-agent and
returns its answer. The model sees one tool per agent instead of the task tools, so a
single delegation costs fewer model calls and fewer prompt tokens; the calling agent does
not start sub-agents in parallel on its own account.