Class: MCP::Elicitation::EnumSchema

Inherits:
Object
  • Object
show all
Defined in:
lib/mcp/elicitation/enum_schema.rb

Overview

Builds the four enum schema variants defined by MCP 2025-11-25 (SEP-1330) plus the legacy enumNames form retained for backward compatibility.

Each class method returns an EnumSchema instance; call to_h to get the property-value Hash and pass it through requested_schema to ServerSession#create_form_elicitation.

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(type:, extras:, default: nil, title: nil, description: nil) ⇒ EnumSchema

Returns a new instance of EnumSchema.



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# File 'lib/mcp/elicitation/enum_schema.rb', line 104

def initialize(type:, extras:, default: nil, title: nil, description: nil)
  @type = type
  @extras = extras
  @default = default
  @title = title
  @description = description
end

Class Method Details

.legacy_titled(values:, value_titles:, default: nil, title: nil, description: nil) ⇒ Object

Legacy single-select retained for backward compatibility with clients implementing the pre-SEP-1330 form: { enum, enumNames }.



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# File 'lib/mcp/elicitation/enum_schema.rb', line 68

def legacy_titled(values:, value_titles:, default: nil, title: nil, description: nil)
  validate_values!(values)
  unless value_titles.is_a?(Array) && value_titles.length == values.length
    raise ArgumentError, "value_titles must be an Array of the same length as values"
  end

  new(
    type: "string",
    extras: { enum: values, enumNames: value_titles },
    default: default,
    title: title,
    description: description,
  )
end

.titled_multi_select(options:, default: nil, title: nil, description: nil) ⇒ Object

Multi-select with display titles per option: { type: "array", items: { anyOf: [{ const, title }, ...] } }.



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# File 'lib/mcp/elicitation/enum_schema.rb', line 53

def titled_multi_select(options:, default: nil, title: nil, description: nil)
  validate_titled_options!(options)

  items_anyof = options.map { |o| { const: o[:value], title: o[:title] } }
  new(
    type: "array",
    extras: { items: { anyOf: items_anyof } },
    default: default,
    title: title,
    description: description,
  )
end

.titled_single_select(options:, default: nil, title: nil, description: nil) ⇒ Object

Single-select with display titles per option: { type: "string", oneOf: [{ const, title }, ...] }. options is an Array of { value:, title: } hashes.



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# File 'lib/mcp/elicitation/enum_schema.rb', line 27

def titled_single_select(options:, default: nil, title: nil, description: nil)
  validate_titled_options!(options)

  new(
    type: "string",
    extras: { oneOf: options.map { |o| { const: o[:value], title: o[:title] } } },
    default: default,
    title: title,
    description: description,
  )
end

.untitled_multi_select(values:, default: nil, title: nil, description: nil) ⇒ Object

Multi-select with plain string values: { type: "array", items: { type: "string", enum: [...] } }.



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# File 'lib/mcp/elicitation/enum_schema.rb', line 40

def untitled_multi_select(values:, default: nil, title: nil, description: nil)
  validate_values!(values)

  new(
    type: "array",
    extras: { items: { type: "string", enum: values } },
    default: default,
    title: title,
    description: description,
  )
end

.untitled_single_select(values:, default: nil, title: nil, description: nil) ⇒ Object

Single-select with plain string values: { type: "string", enum: [...] }.



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# File 'lib/mcp/elicitation/enum_schema.rb', line 13

def untitled_single_select(values:, default: nil, title: nil, description: nil)
  validate_values!(values)

  new(
    type: "string",
    extras: { enum: values },
    default: default,
    title: title,
    description: description,
  )
end

Instance Method Details

#to_h ⇒ Object 



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# File 'lib/mcp/elicitation/enum_schema.rb', line 112

def to_h
  hash = { type: @type }.merge(@extras)
  hash[:title] = @title if @title
  hash[:description] = @description if @description
  hash[:default] = @default unless @default.nil?
  hash
end