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.



26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 26

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.



24
25
26
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 24

def mcp_server
  @mcp_server
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



24
25
26
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 24

def name
  @name
end

#prompts ⇒ Object (readonly)

Returns the value of attribute prompts.



24
25
26
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 24

def prompts
  @prompts
end

#resources ⇒ Object (readonly)

Returns the value of attribute resources.



24
25
26
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 24

def resources
  @resources
end

#tools ⇒ Object (readonly)

Returns the value of attribute tools.



24
25
26
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 24

def tools
  @tools
end

#version ⇒ Object (readonly)

Returns the value of attribute version.



24
25
26
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 24

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



78
79
80
81
82
83
84
85
86
87
88
89
90
91
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 78

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



140
141
142
143
144
145
146
147
148
149
150
151
152
153
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 140

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



55
56
57
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 55

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



126
127
128
129
130
131
132
133
134
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 126

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



95
96
97
98
99
100
101
102
103
104
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 95

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



61
62
63
64
65
66
67
68
69
70
71
72
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 61

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[:_meta] = tool.meta if tool.meta
    entry
  end
end

#read_resource(uri) ⇒ Hash

Read a resource by URI (for backward compatibility)

Parameters:

  • uri (String) —

    Resource URI

Returns:

  • (Hash) —

    Resource content



109
110
111
112
113
114
115
116
117
118
119
120
121
122
 
# File 'lib/claude_agent_sdk/sdk_mcp_server.rb', line 109

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