Exception: MCPClient::Errors::InsufficientScopeError

Inherits:

ConnectionError

• Object
• StandardError
• MCPError
• ConnectionError
• MCPClient::Errors::InsufficientScopeError

Defined in:

lib/mcp_client/errors.rb

Overview

Raised for an HTTP 403 with a WWW-Authenticate insufficient_scope challenge (MCP 2025-11-25 / SEP-835). Exposes the challenge parameters so hosts can run a step-up authorization flow with the required scopes.

Instance Attribute Summary

• #error_description ⇒ String^? readonly

  The challenge's human-readable error description.

• #scope ⇒ String^? readonly

  The scopes required by the server's challenge.

Instance Method Summary

• #initialize(message, scope: nil, error_description: nil) ⇒ InsufficientScopeError constructor

  A new instance of InsufficientScopeError.

Constructor Details

#initialize(message, scope: nil, error_description: nil) ⇒ InsufficientScopeError

Returns a new instance of InsufficientScopeError.

Parameters:

• message (String) —

  error message

• scope (String, nil) (defaults to: nil) —

  scopes from the challenge's scope parameter

• error_description (String, nil) (defaults to: nil) —

  challenge error_description

# File 'lib/mcp_client/errors.rb', line 50

def initialize(message, scope: nil, error_description: nil)
  super(message)
  @scope = scope
  @error_description = error_description
end

Instance Attribute Details

#error_description ⇒ String^? (readonly)

Returns the challenge's human-readable error description.

Returns:

• (String, nil) —

  the challenge's human-readable error description

# File 'lib/mcp_client/errors.rb', line 45

def error_description
  @error_description
end

#scope ⇒ String^? (readonly)

Returns the scopes required by the server's challenge.

Returns:

• (String, nil) —

  the scopes required by the server's challenge

# File 'lib/mcp_client/errors.rb', line 43

def scope
  @scope
end