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

# Anomaly Detection

> How Muster detects and alerts on unusual agent behaviour.

Muster automatically detects anomalies in agent cost and quality patterns without requiring you to configure thresholds.

## Anomaly types

| Type                     | Trigger                                                   |
| ------------------------ | --------------------------------------------------------- |
| **Cost spike**           | Daily cost > 1.3× 30-day baseline for 3+ consecutive days |
| **Frequency change**     | Job frequency drops or spikes by >50% vs baseline         |
| **Error surge**          | Failed jobs exceed 20% of total jobs                      |
| **Endpoint unreachable** | Agent's endpoint fails health probe 3× in a row           |
| **Model change**         | Agent starts using a different model than registered      |

## Anomaly lifecycle

```
Detected → Active → Acknowledged → Resolved
```

* **Active** — anomaly is ongoing, shown in the Executive Summary
* **Acknowledged** — a team member has noted it (adds name + timestamp)
* **Resolved** — anomaly condition no longer met

## Acknowledging anomalies

Click any anomaly in the Executive Summary or agent detail to acknowledge it. This removes it from the active count but keeps it in the history.

## Cost spike example

If your `invoice-processor-v2` normally costs $14/day but starts costing $21/day:

* Spike ratio: 1.41×
* Baseline: \$15.13 (30-day average)
* Observed: \$21.33 (10-day average)
* Status: Active anomaly, severity HIGH