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exceptions

Custom exceptions for MCPServer.

MCPServerError

Bases: Exception

Base error for MCPServer.

Source code in src/mcp/server/mcpserver/exceptions.py 
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class MCPServerError(Exception):
    """Base error for MCPServer."""

ValidationError

Bases: MCPServerError

Error in validating parameters or return values.

Source code in src/mcp/server/mcpserver/exceptions.py 
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class ValidationError(MCPServerError):
    """Error in validating parameters or return values."""

ResourceError

Bases: MCPServerError

Error in resource operations.

Source code in src/mcp/server/mcpserver/exceptions.py 
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class ResourceError(MCPServerError):
    """Error in resource operations."""

ResourceNotFoundError

Bases: ResourceError

Resource does not exist.

Raise this from a resource template handler to signal that the requested instance does not exist; clients receive -32602 (invalid params) per SEP-2164.

Source code in src/mcp/server/mcpserver/exceptions.py 
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class ResourceNotFoundError(ResourceError):
    """Resource does not exist.

    Raise this from a resource template handler to signal that the requested instance does not exist;
    clients receive `-32602` (invalid params) per
    [SEP-2164](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2164).
    """

ToolError

Bases: MCPServerError

Error in tool operations.

Source code in src/mcp/server/mcpserver/exceptions.py 
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class ToolError(MCPServerError):
    """Error in tool operations."""

InvalidSignature

Bases: Exception

Invalid signature for use with MCPServer.

Source code in src/mcp/server/mcpserver/exceptions.py 
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class InvalidSignature(Exception):
    """Invalid signature for use with MCPServer."""