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

# mime

# `fastmcp.utilities.mime`

MIME type constants and helpers for MCP Apps UI resources.

This module has no dependencies on the server or resource packages,
so it can be safely imported from anywhere.

## Functions

### `resolve_ui_mime_type` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/utilities/mime.py#L10" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}}
resolve_ui_mime_type(uri: str, explicit_mime_type: str | None) -> str | None
```

Return the appropriate MIME type for a resource URI.

For `ui://` scheme resources, defaults to `UI_MIME_TYPE` when no
explicit MIME type is provided.

**Args:**

* `uri`: The resource URI string
* `explicit_mime_type`: The MIME type explicitly provided by the user

**Returns:**

* The resolved MIME type (explicit value, UI default, or None)