Class: ClaudeAgentSDK::Client

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

Overview

Client for bidirectional, interactive conversations with Claude Code

This client provides full control over the conversation flow with support for streaming, hooks, permission callbacks, and dynamic message sending. The Client class always uses streaming mode for bidirectional communication.

Examples:

Basic usage

Async do
  client = ClaudeAgentSDK::Client.new
  client.connect  # No arguments needed - automatically uses streaming mode

  client.query("What is the capital of France?")
  client.receive_response do |msg|
    puts msg if msg.is_a?(ClaudeAgentSDK::AssistantMessage)
  end

  client.disconnect
end

With hooks

options = ClaudeAgentOptions.new(
  hooks: {
    'PreToolUse' => [
      HookMatcher.new(
        matcher: 'Bash',
        hooks: [
          ->(input, tool_use_id, context) {
            # Return hook output
            {}
          }
        ]
      )
    ]
  }
)
client = ClaudeAgentSDK::Client.new(options: options)

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options: nil) ⇒ Client

Returns a new instance of Client.



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# File 'lib/claude_agent_sdk.rb', line 124

def initialize(options: nil)
  @options = options || ClaudeAgentOptions.new
  @transport = nil
  @query_handler = nil
  @connected = false
  ENV['CLAUDE_CODE_ENTRYPOINT'] = 'sdk-rb-client'
end

Instance Attribute Details

#query_handler ⇒ Object (readonly)

Returns the value of attribute query_handler.



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# File 'lib/claude_agent_sdk.rb', line 122

def query_handler
  @query_handler
end

Instance Method Details

#connect(prompt = nil) ⇒ Object

Connect to Claude with optional initial prompt

Parameters:

  • prompt (String, Enumerator, nil) (defaults to: nil) —

    Initial prompt or message stream



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# File 'lib/claude_agent_sdk.rb', line 134

def connect(prompt = nil)
  return if @connected

  # Validate and configure permission settings
  configured_options = @options
  if @options.can_use_tool
    # can_use_tool requires streaming mode
    if prompt.is_a?(String)
      raise ArgumentError, 'can_use_tool callback requires streaming mode'
    end

    # can_use_tool and permission_prompt_tool_name are mutually exclusive
    if @options.permission_prompt_tool_name
      raise ArgumentError, 'can_use_tool callback cannot be used with permission_prompt_tool_name'
    end

    # Set permission_prompt_tool_name to stdio for control protocol
    configured_options = @options.dup_with(permission_prompt_tool_name: 'stdio')
  end

  # Auto-connect with empty enumerator if no prompt is provided
  # This matches the Python SDK pattern where ClaudeSDKClient always uses streaming mode
  # An empty enumerator keeps stdin open for bidirectional communication
  actual_prompt = prompt || [].to_enum
  @transport = SubprocessCLITransport.new(actual_prompt, configured_options)
  @transport.connect

  # Extract SDK MCP servers
  sdk_mcp_servers = {}
  if configured_options.mcp_servers.is_a?(Hash)
    configured_options.mcp_servers.each do |name, config|
      sdk_mcp_servers[name] = config[:instance] if config.is_a?(Hash) && config[:type] == 'sdk'
    end
  end

  # Convert hooks to internal format
  hooks = convert_hooks_to_internal_format(configured_options.hooks) if configured_options.hooks

  # Create Query handler
  @query_handler = Query.new(
    transport: @transport,
    is_streaming_mode: true,
    can_use_tool: configured_options.can_use_tool,
    hooks: hooks,
    sdk_mcp_servers: sdk_mcp_servers
  )

  # Start query handler and initialize
  @query_handler.start
  @query_handler.initialize_protocol

  @connected = true
end

#disconnect ⇒ Object

Disconnect from Claude



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# File 'lib/claude_agent_sdk.rb', line 254

def disconnect
  return unless @connected

  @query_handler&.close
  @query_handler = nil
  @transport = nil
  @connected = false
end

#interrupt ⇒ Object

Send interrupt signal

Raises:



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# File 'lib/claude_agent_sdk.rb', line 228

def interrupt
  raise CLIConnectionError, 'Not connected. Call connect() first' unless @connected
  @query_handler.interrupt
end

#query(prompt, session_id: 'default') ⇒ Object

Send a query to Claude

Parameters:

  • prompt (String) —

    The prompt to send

  • session_id (String) (defaults to: 'default') —

    Session identifier

Raises:



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# File 'lib/claude_agent_sdk.rb', line 191

def query(prompt, session_id: 'default')
  raise CLIConnectionError, 'Not connected. Call connect() first' unless @connected

  message = {
    type: 'user',
    message: { role: 'user', content: prompt },
    parent_tool_use_id: nil,
    session_id: session_id
  }
  @transport.write(JSON.generate(message) + "\n")
end

#receive_messages {|Message| ... } ⇒ Object

Receive all messages from Claude

Yields:

  • (Message) —

    Each message received

Raises:



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# File 'lib/claude_agent_sdk.rb', line 205

def receive_messages(&block)
  return enum_for(:receive_messages) unless block

  raise CLIConnectionError, 'Not connected. Call connect() first' unless @connected

  @query_handler.receive_messages do |data|
    message = MessageParser.parse(data)
    block.call(message)
  end
end

#receive_response {|Message| ... } ⇒ Object

Receive messages until a ResultMessage is received

Yields:

  • (Message) —

    Each message received



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# File 'lib/claude_agent_sdk.rb', line 218

def receive_response(&block)
  return enum_for(:receive_response) unless block

  receive_messages do |message|
    block.call(message)
    break if message.is_a?(ResultMessage)
  end
end

#server_info ⇒ Hash?

Get server initialization info

Returns:

  • (Hash, nil) —

    Server info or nil



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# File 'lib/claude_agent_sdk.rb', line 249

def server_info
  @query_handler&.instance_variable_get(:@initialization_result)
end

#set_model(model) ⇒ Object

Change the AI model during conversation

Parameters:

  • model (String, nil) —

    Model name or nil for default

Raises:



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# File 'lib/claude_agent_sdk.rb', line 242

def set_model(model)
  raise CLIConnectionError, 'Not connected. Call connect() first' unless @connected
  @query_handler.set_model(model)
end

#set_permission_mode(mode) ⇒ Object

Change permission mode during conversation

Parameters:

  • mode (String) —

    Permission mode (‘default’, ‘acceptEdits’, ‘bypassPermissions’)

Raises:



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# File 'lib/claude_agent_sdk.rb', line 235

def set_permission_mode(mode)
  raise CLIConnectionError, 'Not connected. Call connect() first' unless @connected
  @query_handler.set_permission_mode(mode)
end