---
title: function_prompt
sidebarTitle: function_prompt
---

# `fastmcp.prompts.function_prompt`


Standalone @prompt decorator for FastMCP.

## Functions

### `prompt` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/prompts/function_prompt.py#L433" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
prompt(name_or_fn: str | Callable[..., Any] | None = None) -> Any
```


Standalone decorator to mark a function as an MCP prompt.

Returns the original function with metadata attached. Register with a server
using mcp.add_prompt().


## Classes

### `DecoratedPrompt` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/prompts/function_prompt.py#L54" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


Protocol for functions decorated with @prompt.


### `PromptMeta` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/prompts/function_prompt.py#L63" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


Metadata attached to functions by the @prompt decorator.


### `FunctionPrompt` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/prompts/function_prompt.py#L79" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


A prompt that is a function.


**Methods:**

#### `from_function` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/prompts/function_prompt.py#L85" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
from_function(cls, fn: Callable[..., Any]) -> FunctionPrompt
```

Create a Prompt from a function.

**Args:**
- `fn`: The function to wrap
- `metadata`: PromptMeta object with all configuration. If provided,
individual parameters must not be passed.
- `name, title, etc.`: Individual parameters for backwards compatibility.
Cannot be used together with metadata parameter.

The function can return:
- str: wrapped as single user Message
- list\[Message | str]: converted to list\[Message]
- PromptResult: used directly


#### `render` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/prompts/function_prompt.py#L318" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
render(self, arguments: dict[str, Any] | None = None) -> PromptResult
```

Render the prompt with arguments.


#### `register_with_docket` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/prompts/function_prompt.py#L370" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
register_with_docket(self, docket: Docket) -> None
```

Register this prompt with docket for background execution.


#### `add_to_docket` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/prompts/function_prompt.py#L376" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
add_to_docket(self, docket: Docket, arguments: dict[str, Any] | None, **kwargs: Any) -> Execution
```

Schedule this prompt for background execution via docket.

FunctionPrompt splats the arguments dict since .fn expects **kwargs.

**Args:**
- `docket`: The Docket instance
- `arguments`: Prompt arguments
- `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()

