docs/python-sdk/fastmcp-settings.mdx

---
title: settings
sidebarTitle: settings
---

# `fastmcp.settings`

## Classes

### `ExtendedEnvSettingsSource`


A special EnvSettingsSource that allows for multiple env var prefixes to be used.

Raises a deprecation warning if the old `FASTMCP_SERVER_` prefix is used.


**Methods:**

#### `get_field_value`

```python
get_field_value(self, field: FieldInfo, field_name: str) -> tuple[Any, str, bool]
```

### `ExtendedSettingsConfigDict`

### `Settings`


FastMCP settings.


**Methods:**

#### `settings_customise_sources`

```python
settings_customise_sources(cls, settings_cls: type[BaseSettings], init_settings: PydanticBaseSettingsSource, env_settings: PydanticBaseSettingsSource, dotenv_settings: PydanticBaseSettingsSource, file_secret_settings: PydanticBaseSettingsSource) -> tuple[PydanticBaseSettingsSource, ...]
```

#### `settings`

```python
settings(self) -> Self
```

This property is for backwards compatibility with FastMCP < 2.8.0,
which accessed fastmcp.settings.settings


#### `setup_logging`

```python
setup_logging(self) -> Self
```

Finalize the settings.