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

# Topics automation idle timeout and trace update behavior

> [!NOTE]
>
> **Applies to:**
>
> * Plan - Any
> * Deployment - Any
> *
> * Use case: Understanding when Topics automation runs and how trace updates affect topic generation timing

## Summary

**Goal:** Control when Topics automation processes a trace by configuring the idle timeout setting.

**Features:** Topics automation, idle timeout, sampling rate, Evaluators tab

## How Topics automation is triggered

Topics does not support a manual trigger or per-trace flag for incoming traces. Processing is controlled by two settings:

* **Sampling rate** — which traces are eligible for topic generation
* **Idle timeout** — how long a trace must be idle before Topics processes it (default: 600 seconds, minimum: 10 seconds)

Topics batch-processes all traces that have been idle beyond the configured threshold.

## Idle timeout reset behavior

The idle timeout resets whenever a trace becomes active again. This means Topics automation will re-run on traces that have already been processed:

1. Topics runs on a trace after the idle timeout elapses
2. You update the trace (e.g., append human actions, mark it closed)
3. The idle timeout resets
4. Topics re-runs on the updated trace after the timeout elapses again

This allows topic generation to include both AI and human portions of a conversation after the trace is closed.

## Configuration

To minimize delay between trace completion and topic generation, reduce the idle timeout to its minimum value.

**Location:** Topics automation settings → **Idle timeout (seconds)**

Set to `10` for near-immediate processing after a trace becomes idle.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.