---
title: exceptions
sidebarTitle: exceptions
---

# `fastmcp.exceptions`


Custom exceptions for FastMCP.

## Classes

### `FastMCPError`


Base error for FastMCP.


### `ValidationError`


Error in validating parameters or return values.


### `ResourceError`


Error in resource operations.


### `ToolError`


Error in tool operations.


### `PromptError`


Error in prompt operations.


### `InvalidSignature`


Invalid signature for use with FastMCP.


### `ClientError`


Error in client operations.


### `NotFoundError`


Object not found.


### `DisabledError`


Object is disabled.

