fastmcp/docs/python-sdk/fastmcp-resources-resource.mdx
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---
title: resource
sidebarTitle: resource
---
# `fastmcp.resources.resource`
Base classes and interfaces for FastMCP resources.
## Classes
### `ResourceContent` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L36" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
Wrapper for resource content with optional MIME type and metadata.
Accepts any value for content - strings and bytes pass through directly,
other types (dict, list, BaseModel, etc.) are automatically JSON-serialized.
**Methods:**
#### `to_mcp_resource_contents` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L91" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
to_mcp_resource_contents(self, uri: AnyUrl | str) -> mcp.types.TextResourceContents | mcp.types.BlobResourceContents
```
Convert to MCP resource contents type.
**Args:**
- `uri`: The URI of the resource (required by MCP types)
**Returns:**
- TextResourceContents for str content, BlobResourceContents for bytes
### `ResourceResult` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L118" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
Canonical result type for resource reads.
Provides explicit control over resource responses: multiple content items,
per-item MIME types, and metadata at both the item and result level.
**Methods:**
#### `to_mcp_result` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L193" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
to_mcp_result(self, uri: AnyUrl | str) -> mcp.types.ReadResourceResult
```
Convert to MCP ReadResourceResult.
**Args:**
- `uri`: The URI of the resource (required by MCP types)
**Returns:**
- MCP ReadResourceResult with converted contents
### `Resource` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L209" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
Base class for all resources.
**Methods:**
#### `from_function` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L234" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
from_function(cls, fn: Callable[..., Any], uri: str | AnyUrl) -> FunctionResource
```
#### `set_default_mime_type` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L273" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
set_default_mime_type(cls, mime_type: str | None) -> str
```
Set default MIME type if not provided.
#### `set_default_name` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L280" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
set_default_name(self) -> Self
```
Set default name from URI if not provided.
#### `read` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L290" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
read(self) -> str | bytes | ResourceResult
```
Read the resource content.
Subclasses implement this to return resource data. Supported return types:
- str: Text content
- bytes: Binary content
- ResourceResult: Full control over contents and result-level meta
#### `convert_result` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L302" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
convert_result(self, raw_value: Any) -> ResourceResult
```
Convert a raw result to ResourceResult.
This is used in two contexts:
1. In _read() to convert user function return values to ResourceResult
2. In tasks_result_handler() to convert Docket task results to ResourceResult
Handles ResourceResult passthrough and converts raw values using
ResourceResult's normalization.
#### `to_mcp_resource` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L358" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
to_mcp_resource(self, **overrides: Any) -> SDKResource
```
Convert the resource to an SDKResource.
#### `key` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L381" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
key(self) -> str
```
The globally unique lookup key for this resource.
#### `register_with_docket` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L386" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
register_with_docket(self, docket: Docket) -> None
```
Register this resource with docket for background execution.
#### `add_to_docket` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L392" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
add_to_docket(self, docket: Docket, **kwargs: Any) -> Execution
```
Schedule this resource for background execution via docket.
**Args:**
- `docket`: The Docket instance
- `fn_key`: Function lookup key in Docket registry (defaults to self.key)
- `task_key`: Redis storage key for the result
- `**kwargs`: Additional kwargs passed to docket.add()
#### `get_span_attributes` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/resources/resource.py#L413" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>
```python
get_span_attributes(self) -> dict[str, Any]
```