Class: ActionMCP::OutputSchemaBuilder

Inherits:
Object
  • Object
show all
Includes:
SchemaHelpers
Defined in:
lib/action_mcp/output_schema_builder.rb

Overview

DSL builder for creating output JSON Schema from Ruby-like syntax Unlike SchemaBuilder, this preserves nested structure for validation

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ OutputSchemaBuilder

Returns a new instance of OutputSchemaBuilder.



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# File 'lib/action_mcp/output_schema_builder.rb', line 14

def initialize
  @properties = {}
  @required = []
end

Instance Attribute Details

#properties ⇒ Object (readonly)

Returns the value of attribute properties.



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# File 'lib/action_mcp/output_schema_builder.rb', line 12

def properties
  @properties
end

#required ⇒ Object (readonly)

Returns the value of attribute required.



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# File 'lib/action_mcp/output_schema_builder.rb', line 12

def required
  @required
end

Instance Method Details

#additional_properties(enabled = nil) ⇒ Object

Set additionalProperties for the root schema

Parameters:

  • enabled (Boolean, Hash) (defaults to: nil) —

    true to allow any additional properties, false to disallow them, or a Hash for typed additional properties



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# File 'lib/action_mcp/output_schema_builder.rb', line 166

def additional_properties(enabled = nil)
  if enabled.nil?
    @additional_properties
  else
    @additional_properties = enabled
  end
end

#array(name, description: nil, min_items: nil, max_items: nil, items: nil, &block) ⇒ Object

Define an array property

Parameters:

  • name (Symbol) —

    Array property name

  • description (String) (defaults to: nil) —

    Property description

  • min_items (Integer) (defaults to: nil) —

    Minimum number of items

  • max_items (Integer) (defaults to: nil) —

    Maximum number of items

  • items (Hash) (defaults to: nil) —

    Items schema (if not using block)

  • block (Proc) —

    Block defining item schema



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# File 'lib/action_mcp/output_schema_builder.rb', line 91

def array(name, description: nil, min_items: nil, max_items: nil, items: nil, &block)
  schema = { "type" => "array" }
  schema["description"] = description if description
  schema["minItems"] = min_items if min_items
  schema["maxItems"] = max_items if max_items

  if block_given?
    # Create nested builder for items
    item_builder = OutputSchemaBuilder.new
    result = item_builder.instance_eval(&block)

    # If the block returned a schema directly (e.g., from string()),
    # use that. Otherwise, build an object schema from properties.
    if result.is_a?(Hash) && result["type"]
      schema["items"] = result
    elsif item_builder.properties.empty?
      # Block didn't define properties, assume string items
      schema["items"] = { "type" => "string" }
    else
      # Block defined object properties
      item_schema = {
        "type" => "object",
        "properties" => item_builder.properties
      }
      item_schema["required"] = item_builder.required if item_builder.required.any?
      schema["items"] = item_schema
    end
  elsif items
    schema["items"] = items
  else
    # Default to string items
    schema["items"] = { "type" => "string" }
  end

  @properties[name.to_s] = schema

  name.to_s
end

#boolean(name, required: false, description: nil, default: nil) ⇒ Object

Define a boolean property



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# File 'lib/action_mcp/output_schema_builder.rb', line 73

def boolean(name, required: false, description: nil, default: nil)
  schema = { "type" => "boolean" }
  schema["description"] = description if description
  schema["default"] = default unless default.nil?

  @properties[name.to_s] = schema
  @required << name.to_s if required

  name.to_s
end

#number(name, required: false, description: nil, minimum: nil, maximum: nil, default: nil) ⇒ Object

Define a number property



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# File 'lib/action_mcp/output_schema_builder.rb', line 58

def number(name, required: false, description: nil, minimum: nil,
           maximum: nil, default: nil)
  schema = { "type" => "number" }
  schema["description"] = description if description
  schema["minimum"] = minimum if minimum
  schema["maximum"] = maximum if maximum
  schema["default"] = default if default

  @properties[name.to_s] = schema
  @required << name.to_s if required

  name.to_s
end

#object(name = nil, required: false, description: nil, additional_properties: nil, &block) ⇒ Object

Define an object property

Parameters:

  • name (Symbol, nil) (defaults to: nil) —

    Object property name. If nil, returns schema directly (for array items)

  • required (Boolean) (defaults to: false) —

    Whether the object is required

  • description (String) (defaults to: nil) —

    Property description

  • additional_properties (Boolean, Hash) (defaults to: nil) —

    Whether to allow additional properties

  • block (Proc) —

    Block defining object properties

Raises:

  • (ArgumentError) 


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# File 'lib/action_mcp/output_schema_builder.rb', line 136

def object(name = nil, required: false, description: nil, additional_properties: nil, &block)
  raise ArgumentError, "Object definition requires a block" unless block_given?

  # Create nested builder for object properties
  object_builder = OutputSchemaBuilder.new
  object_builder.instance_eval(&block)

  schema = {
    "type" => "object",
    "properties" => object_builder.properties
  }
  schema["description"] = description if description
  schema["required"] = object_builder.required if object_builder.required.any?

  # Add additionalProperties if specified
  add_additional_properties_to_schema(schema, additional_properties)

  if name
    @properties[name.to_s] = schema
    @required << name.to_s if required
    name.to_s
  else
    # Return schema directly for use in array items
    schema
  end
end

#property(name, type: "string", required: false, description: nil, **options) ⇒ Object

Define a property with specified type

Parameters:

  • name (Symbol) —

    Property name

  • type (String) (defaults to: "string") —

    JSON Schema type

  • required (Boolean) (defaults to: false) —

    Whether the property is required

  • description (String) (defaults to: nil) —

    Property description

  • options (Hash) —

    Additional JSON Schema options



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# File 'lib/action_mcp/output_schema_builder.rb', line 25

def property(name, type: "string", required: false, description: nil, **options)
  schema = { "type" => type }
  schema["description"] = description if description
  schema.merge!(options) if options.any?

  @properties[name.to_s] = schema
  @required << name.to_s if required

  name.to_s
end

#string(name = nil, required: false, description: nil, format: nil, enum: nil, default: nil, min_length: nil, max_length: nil) ⇒ Object

Define a string property



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# File 'lib/action_mcp/output_schema_builder.rb', line 37

def string(name = nil, required: false, description: nil, format: nil, enum: nil,
           default: nil, min_length: nil, max_length: nil)
  schema = { "type" => "string" }
  schema["description"] = description if description
  schema["format"] = format if format
  schema["enum"] = enum if enum
  schema["default"] = default if default
  schema["minLength"] = min_length if min_length
  schema["maxLength"] = max_length if max_length

  if name
    @properties[name.to_s] = schema
    @required << name.to_s if required
    name.to_s
  else
    # Return schema for use in array items or other contexts
    schema
  end
end

#to_json_schema ⇒ Object

Generate the final JSON Schema



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# File 'lib/action_mcp/output_schema_builder.rb', line 175

def to_json_schema
  schema = {
    "$schema" => SchemaValidator::DEFAULT_DIALECT,
    "type" => "object",
    "properties" => @properties
  }

  schema["required"] = @required.uniq if @required.any?

  # Add additionalProperties if configured
  add_additional_properties_to_schema(schema, @additional_properties)

  schema
end