Class: MCP::ServerContext

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

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(context, progress:, notification_target:, related_request_id: nil, cancellation: nil) ⇒ ServerContext

Returns a new instance of ServerContext.



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# File 'lib/mcp/server_context.rb', line 7

def initialize(context, progress:, notification_target:, related_request_id: nil, cancellation: nil)
  @context = context
  @progress = progress
  @notification_target = notification_target
  @related_request_id = related_request_id
  @cancellation = cancellation
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(name, *args, **kwargs, &block) ⇒ Object

Forward arguments explicitly with *args, **kwargs, &block rather than the ... forwarding syntax. The gem supports Ruby 2.7.0 (see required_ruby_version), but RuboCop's Parser backend only runs on Ruby 2.7.8, so leading-argument forwarding like def method_missing(name, ...) is allowed by the linter even though it raises a SyntaxError on Ruby 2.7.0 through 2.7.2 (it was added in Ruby 2.7.3). Explicit forwarding keeps this method loadable on Ruby 2.7.0.



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# File 'lib/mcp/server_context.rb', line 160

def method_missing(name, *args, **kwargs, &block)
  if @context.respond_to?(name)
    @context.public_send(name, *args, **kwargs, &block)
  else
    super
  end
end

Instance Attribute Details

#cancellation ⇒ Object (readonly)

Returns the value of attribute cancellation.



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# File 'lib/mcp/server_context.rb', line 5

def cancellation
  @cancellation
end

Instance Method Details

#cancelled? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/mcp/server_context.rb', line 15

def cancelled?
  !!@cancellation&.cancelled?
end

#create_form_elicitation(**kwargs) ⇒ Object

Delegates to the session so the request is scoped to the originating client. Falls back to @context (via method_missing) when @notification_target does not support elicitation. The originating request id is stamped as a non-overridable related_request_id, as with create_sampling_message (SEP-2260).



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# File 'lib/mcp/server_context.rb', line 120

def create_form_elicitation(**kwargs)
  if @notification_target.respond_to?(:create_form_elicitation)
    @notification_target.create_form_elicitation(**kwargs, related_request_id: @related_request_id)
  elsif @context.respond_to?(:create_form_elicitation)
    @context.create_form_elicitation(**kwargs, related_request_id: @related_request_id)
  else
    raise NoMethodError, "undefined method 'create_form_elicitation' for #{self}"
  end
end

#create_sampling_message(**kwargs) ⇒ Object

Deprecated.

MCP Sampling (sampling/createMessage) is deprecated as of MCP protocol version 2026-07-28 (SEP-2577). Use direct LLM provider APIs instead.

Delegates to the session so the request is scoped to the originating client. Falls back to @context (via method_missing) when @notification_target does not support sampling.

The originating request id is stamped as related_request_id and cannot be overridden by callers (the literal keyword after **kwargs wins), satisfying SEP-2260's requirement that server-to-client requests be associated with the client request being processed.



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# File 'lib/mcp/server_context.rb', line 105

def create_sampling_message(**kwargs)
  if @notification_target.respond_to?(:create_sampling_message)
    @notification_target.create_sampling_message(**kwargs, related_request_id: @related_request_id)
  elsif @context.respond_to?(:create_sampling_message)
    @context.create_sampling_message(**kwargs, related_request_id: @related_request_id)
  else
    raise NoMethodError, "undefined method 'create_sampling_message' for #{self}"
  end
end

#create_url_elicitation(**kwargs) ⇒ Object

Delegates to the session so the request is scoped to the originating client. Falls back to @context when @notification_target does not support URL mode elicitation. The originating request id is stamped as a non-overridable related_request_id, as with create_sampling_message (SEP-2260).



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# File 'lib/mcp/server_context.rb', line 134

def create_url_elicitation(**kwargs)
  if @notification_target.respond_to?(:create_url_elicitation)
    @notification_target.create_url_elicitation(**kwargs, related_request_id: @related_request_id)
  elsif @context.respond_to?(:create_url_elicitation)
    @context.create_url_elicitation(**kwargs, related_request_id: @related_request_id)
  else
    raise NoMethodError, "undefined method 'create_url_elicitation' for #{self}"
  end
end

#list_roots ⇒ Object

Deprecated.

MCP Roots (roots/list and notifications/roots/list_changed) is deprecated as of MCP protocol version 2026-07-28 (SEP-2577). Use tool parameters, resource URIs, server configuration, or environment variables instead.

Delegates to the session so the request is scoped to the originating client. The originating request id is stamped as related_request_id, satisfying SEP-2260's requirement that server-to-client requests be associated with the client request being processed.



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# File 'lib/mcp/server_context.rb', line 64

def list_roots
  if @notification_target.respond_to?(:list_roots)
    @notification_target.list_roots(related_request_id: @related_request_id)
  else
    raise NoMethodError, "undefined method 'list_roots' for #{self}"
  end
end

#notify_elicitation_complete(**kwargs) ⇒ Object

Delegates to the session so the notification is scoped to the originating client.



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# File 'lib/mcp/server_context.rb', line 145

def notify_elicitation_complete(**kwargs)
  if @notification_target.respond_to?(:notify_elicitation_complete)
    @notification_target.notify_elicitation_complete(**kwargs)
  elsif @context.respond_to?(:notify_elicitation_complete)
    @context.notify_elicitation_complete(**kwargs)
  else
    raise NoMethodError, "undefined method 'notify_elicitation_complete' for #{self}"
  end
end

#notify_log_message(data:, level:, logger: nil) ⇒ Object

Deprecated.

MCP Logging (logging/setLevel and notifications/message) is deprecated as of MCP protocol version 2026-07-28 (SEP-2577). Use stderr or OpenTelemetry instead.

Sends a log message notification scoped to the originating session.

Parameters:

  • data (Object) —

    The log data to send.

  • level (String) —

    Log level (e.g., "debug", "info", "error").

  • logger (String, nil) (defaults to: nil) —

    Logger name.



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# File 'lib/mcp/server_context.rb', line 41

def notify_log_message(data:, level:, logger: nil)
  return unless @notification_target

  @notification_target.notify_log_message(data: data, level: level, logger: logger, related_request_id: @related_request_id)
end

#notify_resources_updated(uri:) ⇒ Object

Sends a resource updated notification scoped to the originating session.

Parameters:

  • uri (String) —

    The URI of the updated resource.



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# File 'lib/mcp/server_context.rb', line 50

def notify_resources_updated(uri:)
  return unless @notification_target

  @notification_target.notify_resources_updated(uri: uri)
end

#ping ⇒ Hash

Sends a ping request to the originating client to verify it is still responsive. Per the MCP spec, the client MUST respond promptly with an empty result.

Examples:

def self.call(server_context:)
  server_context.ping # => {}
  # ...
end

Returns:

  • (Hash) —

    An empty hash on success.

Raises:

  • (Server::ValidationError) —

    If the response result is not a Hash.

  • (NoMethodError) —

    If the session does not support sending pings.

See Also:



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# File 'lib/mcp/server_context.rb', line 86

def ping
  if @notification_target.respond_to?(:ping)
    @notification_target.ping(related_request_id: @related_request_id)
  else
    raise NoMethodError, "undefined method 'ping' for #{self}"
  end
end

#raise_if_cancelled! ⇒ Object 



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# File 'lib/mcp/server_context.rb', line 19

def raise_if_cancelled!
  @cancellation&.raise_if_cancelled!
end

#report_progress(progress, total: nil, message: nil) ⇒ Object

Reports progress for the current tool operation. The notification is automatically scoped to the originating session.

Parameters:

  • progress (Numeric) —

    Current progress value.

  • total (Numeric, nil) (defaults to: nil) —

    Total expected value.

  • message (String, nil) (defaults to: nil) —

    Human-readable status message.



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# File 'lib/mcp/server_context.rb', line 29

def report_progress(progress, total: nil, message: nil)
  @progress.report(progress, total: total, message: message)
end

#respond_to_missing?(name, include_private = false) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/mcp/server_context.rb', line 168

def respond_to_missing?(name, include_private = false)
  @context.respond_to?(name) || super
end