---
title: tool_injection
sidebarTitle: tool_injection
---

# `fastmcp.server.middleware.tool_injection`


A middleware for injecting tools into the MCP server context.

## Functions

### `list_prompts` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/server/middleware/tool_injection.py#L57" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
list_prompts(context: Context) -> list[Prompt]
```


List prompts available on the server.


### `get_prompt` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/server/middleware/tool_injection.py#L67" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
get_prompt(context: Context, name: Annotated[str, 'The name of the prompt to render.'], arguments: Annotated[dict[str, Any] | None, 'The arguments to pass to the prompt.'] = None) -> mcp.types.GetPromptResult
```


Render a prompt available on the server.


### `list_resources` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/server/middleware/tool_injection.py#L102" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
list_resources(context: Context) -> list[mcp.types.Resource]
```


List resources available on the server.


### `read_resource` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/server/middleware/tool_injection.py#L112" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
read_resource(context: Context, uri: Annotated[AnyUrl | str, 'The URI of the resource to read.']) -> ResourceResult
```


Read a resource available on the server.


## Classes

### `ToolInjectionMiddleware` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/server/middleware/tool_injection.py#L24" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


A middleware for injecting tools into the context.


**Methods:**

#### `on_list_tools` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/server/middleware/tool_injection.py#L35" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
on_list_tools(self, context: MiddlewareContext[mcp.types.ListToolsRequest], call_next: CallNext[mcp.types.ListToolsRequest, Sequence[Tool]]) -> Sequence[Tool]
```

Inject tools into the response.


#### `on_call_tool` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/server/middleware/tool_injection.py#L44" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
on_call_tool(self, context: MiddlewareContext[mcp.types.CallToolRequestParams], call_next: CallNext[mcp.types.CallToolRequestParams, ToolResult]) -> ToolResult
```

Intercept tool calls to injected tools.


### `PromptToolMiddleware` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/server/middleware/tool_injection.py#L83" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


A middleware for injecting prompts as tools into the context.

.. deprecated::
    Use ``fastmcp.server.transforms.PromptsAsTools`` instead.


### `ResourceToolMiddleware` <sup><a href="https://github.com/PrefectHQ/fastmcp/blob/main/src/fastmcp/server/middleware/tool_injection.py#L125" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


A middleware for injecting resources as tools into the context.

.. deprecated::
    Use ``fastmcp.server.transforms.ResourcesAsTools`` instead.

