---
title: "Supervisors"
description: "Supervisors monitor agents and automatically restart them on failure. Inspired by Erlang/OTP supervision trees, they provide fault tolerance for your agent systems. Strategy Behavior one for one Restart only the failed a"
resource: https://www.aiagents.nexus/docs/orchestration/supervisors
generated: { by: "process:nexus-agent-assets", at: 2026-09-07T09:13:03Z }
status: stable
---

# Supervisors

Supervisors monitor agents and automatically restart them on failure. Inspired by Erlang/OTP supervision trees, they provide fault tolerance for your agent systems.

## Strategies

| Strategy | Behavior |
|---|---|
| `one-for-one` | Restart only the failed agent |
| `one-for-all` | Restart all children if one fails |
| `rest-for-one` | Restart failed agent and all agents started after it |

## Creating a Supervisor

```bash
# Create supervisor with strategy
naos supervisor create main --strategy one-for-one --max-restarts 3

# Add child agents
naos supervisor add main researcher
naos supervisor add main analyzer

# Start the supervisor (starts all children)
naos supervisor start main
```

## Supervisor Tree

View the supervision tree:

```bash
naos supervisor status main
```

Output:

```
SUPERVISOR: main
Strategy: one-for-one | Max Restarts: 3 | Status: running

CHILDREN:
  ├── researcher  running   4h 12m
  └── analyzer    running   4h 12m

RESTARTS: 0/3
```

## Configuration

Define supervisors in `nexus.config.yaml`:

```yaml
supervisors:
  main:
    strategy: one-for-one
    maxRestarts: 3
    children:
      - researcher
      - analyzer
  pipeline:
    strategy: rest-for-one
    maxRestarts: 5
    children:
      - fetcher
      - processor
      - writer
```

## Restart Behavior

When an agent fails:

1. Supervisor detects the failure
2. Applies the restart strategy
3. Increments the restart counter
4. If max restarts exceeded, supervisor itself fails
5. Parent supervisor (if any) handles the failure

## Nested Supervisors

Supervisors can supervise other supervisors:

```bash
naos supervisor create root --strategy one-for-one
naos supervisor add root main
naos supervisor add root pipeline
naos supervisor start root
```