ruby-sdk/lib/mcp/tool/input_schema.rb
Tyler Rowsell 600c96f66a Validate ToolCall Args against Schema
(cherry picked from commit eeb287117535dfb43785704171625323f01d5bda)
2025-06-04 15:19:05 -04:00

57 lines
1.6 KiB
Ruby

# frozen_string_literal: true
require "json-schema"
module MCP
class Tool
class InputSchema
class ValidationError < StandardError; end
attr_reader :properties, :required
def initialize(properties: {}, required: [])
@properties = properties
@required = required.map(&:to_sym)
validate_schema!
end
def to_h
{ type: "object", properties:, required: }
end
def missing_required_arguments?(arguments)
missing_required_arguments(arguments).any?
end
def missing_required_arguments(arguments)
(required - arguments.keys.map(&:to_sym))
end
def validate_arguments(arguments)
errors = JSON::Validator.fully_validate(to_h, arguments)
if errors.any?
raise ValidationError, "Invalid arguments: #{errors.join(", ")}"
end
end
private
def validate_schema!
schema = to_h
begin
schema_reader = JSON::Schema::Reader.new(
accept_uri: false,
accept_file: ->(path) { path.to_s.start_with?(Gem.loaded_specs["json-schema"].full_gem_path) },
)
metaschema = JSON::Validator.validator_for_name("draft4").metaschema
errors = JSON::Validator.fully_validate(metaschema, schema, schema_reader: schema_reader)
if errors.any?
raise ArgumentError, "Invalid JSON Schema: #{errors.join(", ")}"
end
rescue StandardError => e
raise ArgumentError, "Invalid JSON Schema: #{e.message}"
end
end
end
end
end