Module: ActionMCP::Content::Validation

Defined in:
lib/action_mcp/content/validation.rb

Overview

Stable MCP wire-shape validation shared by content and response value objects.

Constant Summary collapse

META_PROPERTY = 
{
  "_meta" => { "type" => "object" }
}.freeze
ANNOTATIONS = 
{
  "type" => "object",
  "properties" => {
    "audience" => {
      "type" => "array",
      "items" => { "type" => "string", "enum" => %w[assistant user] }
    },
    "lastModified" => { "type" => "string" },
    "priority" => { "type" => "number", "minimum" => 0, "maximum" => 1 }
  }
}.freeze
ICON = 
{
  "type" => "object",
  "required" => [ "src" ],
  "properties" => {
    "src" => { "type" => "string", "format" => "uri" },
    "mimeType" => { "type" => "string" },
    "sizes" => { "type" => "array", "items" => { "type" => "string" } },
    "theme" => { "type" => "string", "enum" => %w[dark light] }
  }
}.freeze
DEFINITIONS = 
{
  "Annotations" => ANNOTATIONS,
  "Icon" => ICON,
  "TextContent" => {
    "type" => "object",
    "required" => %w[text type],
    "properties" => META_PROPERTY.merge(
      "annotations" => { "$ref" => "#/$defs/Annotations" },
      "text" => { "type" => "string" },
      "type" => { "type" => "string", "const" => "text" }
    )
  },
  "ImageContent" => {
    "type" => "object",
    "required" => %w[data mimeType type],
    "properties" => META_PROPERTY.merge(
      "annotations" => { "$ref" => "#/$defs/Annotations" },
      "data" => { "type" => "string", "format" => "byte" },
      "mimeType" => { "type" => "string" },
      "type" => { "type" => "string", "const" => "image" }
    )
  },
  "AudioContent" => {
    "type" => "object",
    "required" => %w[data mimeType type],
    "properties" => META_PROPERTY.merge(
      "annotations" => { "$ref" => "#/$defs/Annotations" },
      "data" => { "type" => "string", "format" => "byte" },
      "mimeType" => { "type" => "string" },
      "type" => { "type" => "string", "const" => "audio" }
    )
  },
  "TextResourceContents" => {
    "type" => "object",
    "required" => %w[text uri],
    "properties" => META_PROPERTY.merge(
      "mimeType" => { "type" => "string" },
      "text" => { "type" => "string" },
      "uri" => { "type" => "string", "format" => "uri" }
    )
  },
  "BlobResourceContents" => {
    "type" => "object",
    "required" => %w[blob uri],
    "properties" => META_PROPERTY.merge(
      "blob" => { "type" => "string", "format" => "byte" },
      "mimeType" => { "type" => "string" },
      "uri" => { "type" => "string", "format" => "uri" }
    )
  },
  "EmbeddedResource" => {
    "type" => "object",
    "required" => %w[resource type],
    "properties" => META_PROPERTY.merge(
      "annotations" => { "$ref" => "#/$defs/Annotations" },
      "resource" => {
        "anyOf" => [
          { "$ref" => "#/$defs/TextResourceContents" },
          { "$ref" => "#/$defs/BlobResourceContents" }
        ]
      },
      "type" => { "type" => "string", "const" => "resource" }
    )
  },
  "ResourceLink" => {
    "type" => "object",
    "required" => %w[name type uri],
    "properties" => META_PROPERTY.merge(
      "annotations" => { "$ref" => "#/$defs/Annotations" },
      "description" => { "type" => "string" },
      "icons" => { "type" => "array", "items" => { "$ref" => "#/$defs/Icon" } },
      "mimeType" => { "type" => "string" },
      "name" => { "type" => "string" },
      "size" => { "type" => "integer" },
      "title" => { "type" => "string" },
      "type" => { "type" => "string", "const" => "resource_link" },
      "uri" => { "type" => "string", "format" => "uri" }
    )
  },
  "ContentBlock" => {
    "anyOf" => %w[TextContent ImageContent AudioContent ResourceLink EmbeddedResource].map do |name|
      { "$ref" => "#/$defs/#{name}" }
    end
  },
  "Resource" => {
    "type" => "object",
    "required" => %w[name uri],
    "properties" => META_PROPERTY.merge(
      "annotations" => { "$ref" => "#/$defs/Annotations" },
      "description" => { "type" => "string" },
      "icons" => { "type" => "array", "items" => { "$ref" => "#/$defs/Icon" } },
      "mimeType" => { "type" => "string" },
      "name" => { "type" => "string" },
      "size" => { "type" => "integer" },
      "title" => { "type" => "string" },
      "uri" => { "type" => "string", "format" => "uri" }
    )
  },
  "PromptMessage" => {
    "type" => "object",
    "required" => %w[content role],
    "properties" => {
      "content" => { "$ref" => "#/$defs/ContentBlock" },
      "role" => { "type" => "string", "enum" => %w[assistant user] }
    }
  },
  "GetPromptResult" => {
    "type" => "object",
    "required" => [ "messages" ],
    "properties" => META_PROPERTY.merge(
      "description" => { "type" => "string" },
      "messages" => { "type" => "array", "items" => { "$ref" => "#/$defs/PromptMessage" } }
    )
  },
  "CallToolResult" => {
    "type" => "object",
    "required" => [ "content" ],
    "properties" => META_PROPERTY.merge(
      "content" => { "type" => "array", "items" => { "$ref" => "#/$defs/ContentBlock" } },
      "isError" => { "type" => "boolean" },
      "structuredContent" => { "type" => "object" }
    )
  }
}.freeze
FORMAT_VALIDATORS = 
{
  "byte" => lambda do |value, _format|
    Base64.strict_decode64(value)
    true
  rescue ArgumentError
    false
  end,
  "uri" => lambda do |value, _format|
    Addressable::URI.parse(value).absolute?
  rescue Addressable::URI::InvalidURIError, TypeError
    false
  end
}.freeze
SCHEMERS = 
%w[Annotations ContentBlock Resource GetPromptResult CallToolResult].to_h do |name|
  schema = {
    "$schema" => "https://json-schema.org/draft/2020-12/schema",
    "$ref" => "#/$defs/#{name}",
    "$defs" => DEFINITIONS
  }
  [ name, JSONSchemer.schema(schema, formats: FORMAT_VALIDATORS) ]
end.freeze

Class Method Summary collapse

Class Method Details

.copy_content_block!(content) ⇒ Object 



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# File 'lib/action_mcp/content/validation.rb', line 229

def copy_content_block!(content)
  copy = copy_object!(content, "content")
  validate_content_block!(copy)
  copy
end

.copy_object!(value, label) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/action_mcp/content/validation.rb', line 212

def copy_object!(value, label)
  source =
    if value.is_a?(Hash)
      value
    elsif value.is_a?(Array)
      nil
    elsif value.respond_to?(:to_hash)
      value.to_hash
    elsif value.respond_to?(:to_h)
      value.to_h
    end

  raise ArgumentError, "#{label} must be a JSON object" unless source.is_a?(Hash)

  source.deep_dup.tap { |copy| ensure_json!(copy, label) }
end

.ensure_json!(value, label) ⇒ Object 



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# File 'lib/action_mcp/content/validation.rb', line 235

def ensure_json!(value, label)
  JSON.generate(value)
rescue JSON::GeneratorError, JSON::NestingError => e
  raise ArgumentError, "#{label} must be JSON-serializable: #{e.message}"
end

.validate_annotations!(annotations) ⇒ Object 



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# File 'lib/action_mcp/content/validation.rb', line 190

def validate_annotations!(annotations)
  return if annotations.nil?

  validate!(SCHEMERS.fetch("Annotations"), annotations, "annotations")
end

.validate_content_block!(content) ⇒ Object 



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# File 'lib/action_mcp/content/validation.rb', line 196

def validate_content_block!(content)
  validate!(SCHEMERS.fetch("ContentBlock"), content, "content")
end

.validate_prompt_result!(result) ⇒ Object 



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# File 'lib/action_mcp/content/validation.rb', line 204

def validate_prompt_result!(result)
  validate!(SCHEMERS.fetch("GetPromptResult"), result, "prompt result")
end

.validate_resource!(resource) ⇒ Object 



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# File 'lib/action_mcp/content/validation.rb', line 200

def validate_resource!(resource)
  validate!(SCHEMERS.fetch("Resource"), resource, "resource")
end

.validate_tool_result!(result) ⇒ Object 



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# File 'lib/action_mcp/content/validation.rb', line 208

def validate_tool_result!(result)
  validate!(SCHEMERS.fetch("CallToolResult"), result, "tool result")
end