Class: ClaudeAgentSDK::SdkMcpServer

Inherits:
Object
  • Object
show all
Defined in:
lib/claude_agent_sdk/sdk_mcp_server.rb

Overview

SDK MCP Server - wraps official MCP::Server with block-based API

Unlike external MCP servers that run as separate processes, SDK MCP servers run directly in your application’s process, providing better performance and simpler deployment.

This class wraps the official MCP Ruby SDK and provides a simpler block-based API for defining tools, resources, and prompts.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name:, version: '1.0.0', tools: [], resources: [], prompts: []) ⇒ SdkMcpServer

Returns a new instance of SdkMcpServer.



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 17

def initialize(name:, version: '1.0.0', tools: [], resources: [], prompts: [])
  @name = name
  @version = version
  @tools = tools
  @resources = resources
  @prompts = prompts

  # Create dynamic Tool classes from tool definitions
  tool_classes = create_tool_classes(tools)

  # Create dynamic Resource classes from resource definitions
  resource_classes = create_resource_classes(resources)

  # Create dynamic Prompt classes from prompt definitions
  prompt_classes = create_prompt_classes(prompts)

  # Create the official MCP::Server instance
  @mcp_server = MCP::Server.new(
    name: name,
    version: version,
    tools: tool_classes,
    resources: resource_classes,
    prompts: prompt_classes
  )
end

Instance Attribute Details

#mcp_server ⇒ Object (readonly)

Returns the value of attribute mcp_server.



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 15

def mcp_server
  @mcp_server
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 15

def name
  @name
end

#prompts ⇒ Object (readonly)

Returns the value of attribute prompts.



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 15

def prompts
  @prompts
end

#resources ⇒ Object (readonly)

Returns the value of attribute resources.



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 15

def resources
  @resources
end

#tools ⇒ Object (readonly)

Returns the value of attribute tools.



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 15

def tools
  @tools
end

#version ⇒ Object (readonly)

Returns the value of attribute version.



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 15

def version
  @version
end

Instance Method Details

#call_tool(name, arguments) ⇒ Hash

Execute a tool by name (for backward compatibility)

Parameters:

  • name (String) —

    Tool name

  • arguments (Hash) —

    Tool arguments

Returns:

  • (Hash) —

    Tool result



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 68

def call_tool(name, arguments)
  tool = @tools.find { |t| t.name == name }
  raise "Tool '#{name}' not found" unless tool

  # Call the tool's handler
  result = tool.handler.call(arguments)

  # Ensure result has the expected format
  unless result.is_a?(Hash) && result[:content]
    raise "Tool '#{name}' must return a hash with :content key"
  end

  result
end

#get_prompt(name, arguments = {}) ⇒ Hash

Get a prompt by name (for backward compatibility)

Parameters:

  • name (String) —

    Prompt name

  • arguments (Hash) (defaults to: {}) —

    Arguments to fill in the prompt template

Returns:

  • (Hash) —

    Prompt with filled-in arguments



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 130

def get_prompt(name, arguments = {})
  prompt = @prompts.find { |p| p.name == name }
  raise "Prompt '#{name}' not found" unless prompt

  # Call the prompt's generator
  result = prompt.generator.call(arguments)

  # Ensure result has the expected format
  unless result.is_a?(Hash) && result[:messages]
    raise "Prompt '#{name}' must return a hash with :messages key"
  end

  result
end

#handle_json(json_string) ⇒ String

Handle a JSON-RPC request

Parameters:

  • json_string (String) —

    JSON-RPC request

Returns:

  • (String) —

    JSON-RPC response



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 46

def handle_json(json_string)
  @mcp_server.handle_json(json_string)
end

#list_prompts ⇒ Array<Hash>

List all available prompts (for backward compatibility)

Returns:

  • (Array<Hash>) —

    Array of prompt definitions



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 116

def list_prompts
  @prompts.map do |prompt|
    {
      name: prompt.name,
      description: prompt.description,
      arguments: prompt.arguments
    }.compact
  end
end

#list_resources ⇒ Array<Hash>

List all available resources (for backward compatibility)

Returns:

  • (Array<Hash>) —

    Array of resource definitions



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 85

def list_resources
  @resources.map do |resource|
    {
      uri: resource.uri,
      name: resource.name,
      description: resource.description,
      mimeType: resource.mime_type
    }.compact
  end
end

#list_tools ⇒ Array<Hash>

List all available tools (for backward compatibility)

Returns:

  • (Array<Hash>) —

    Array of tool definitions



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 52

def list_tools
  @tools.map do |tool|
    entry = {
      name: tool.name,
      description: tool.description,
      inputSchema: convert_input_schema(tool.input_schema)
    }
    entry[:annotations] = tool.annotations if tool.annotations
    entry
  end
end

#read_resource(uri) ⇒ Hash

Read a resource by URI (for backward compatibility)

Parameters:

  • uri (String) —

    Resource URI

Returns:

  • (Hash) —

    Resource content



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 99

def read_resource(uri)
  resource = @resources.find { |r| r.uri == uri }
  raise "Resource '#{uri}' not found" unless resource

  # Call the resource's reader
  content = resource.reader.call

  # Ensure content has the expected format
  unless content.is_a?(Hash) && content[:contents]
    raise "Resource '#{uri}' must return a hash with :contents key"
  end

  content
end