Class: ClaudeAgentSDK::SdkMcpServer

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

Overview

SDK MCP Server - runs in-process within your Ruby application

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.

Supports:

  • Tools: Executable functions that Claude can call

  • Resources: Data sources that can be read (files, databases, APIs, etc.)

  • Prompts: Reusable prompt templates with arguments

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
  @tool_map = tools.each_with_object({}) { |tool, hash| hash[tool.name] = tool }
  @resource_map = resources.each_with_object({}) { |res, hash| hash[res.uri] = res }
  @prompt_map = prompts.each_with_object({}) { |prompt, hash| hash[prompt.name] = prompt }
end

Instance Attribute Details

#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

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 44

def call_tool(name, arguments)
  tool = @tool_map[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

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 106

def get_prompt(name, arguments = {})
  prompt = @prompt_map[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

#list_prompts ⇒ Array<Hash>

List all available prompts

Returns:

  • (Array<Hash>) —

    Array of prompt definitions



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 92

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

Returns:

  • (Array<Hash>) —

    Array of resource definitions



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 61

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

Returns:

  • (Array<Hash>) —

    Array of tool definitions



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 30

def list_tools
  @tools.map do |tool|
    {
      name: tool.name,
      description: tool.description,
      inputSchema: convert_input_schema(tool.input_schema)
    }
  end
end

#read_resource(uri) ⇒ Hash

Read a resource by URI

Parameters:

  • uri (String) —

    Resource URI

Returns:

  • (Hash) —

    Resource content



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# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 75

def read_resource(uri)
  resource = @resource_map[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