Module: Legion::MCP::Server

Extended by:
Logging::Helper
Defined in:
lib/legion/mcp/server.rb

Overview

rubocop:disable Metrics/ModuleLength

Constant Summary collapse

MCP_SPECIFIC_TOOLS =

MCP-specific tools not owned by any extension. All extension-owned tools are discovered via Legion::Settings::Extensions.

[
  Tools::PlanAction,
  Tools::DiscoverTools,
  Tools::StructuralIndexTool,
  Tools::ToolAudit,
  Tools::StateDiff,
  Tools::SearchSessions,
  Tools::SkillList,
  Tools::SkillDescribe,
  Tools::SkillInvoke,
  Tools::SkillCancel
].freeze

Class Attribute Summary collapse

Class Method Summary collapse

Class Attribute Details

.conversation_id ⇒ Object (readonly)

Returns the value of attribute conversation_id.



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# File 'lib/legion/mcp/server.rb', line 48

def conversation_id
  @conversation_id
end

.current_identity ⇒ Object (readonly)

Returns the value of attribute current_identity.



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# File 'lib/legion/mcp/server.rb', line 48

def current_identity
  @current_identity
end

.tool_registry ⇒ Object (readonly)

Returns the value of attribute tool_registry.



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# File 'lib/legion/mcp/server.rb', line 48

def tool_registry
  @tool_registry
end

.trace_id ⇒ Object (readonly)

Returns the value of attribute trace_id.



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# File 'lib/legion/mcp/server.rb', line 48

def trace_id
  @trace_id
end

Class Method Details

.build(identity: nil) ⇒ Object 



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# File 'lib/legion/mcp/server.rb', line 86

def build(identity: nil)
  prepare_build(identity)
  tools = ToolGovernance.filter_tools(tool_registry.dup, identity)

  server = ::MCP::Server.new(
    name:               'legion',
    version:            defined?(Legion::VERSION) ? Legion::VERSION : Legion::MCP::VERSION,
    instructions:       instructions,
    tools:              tools,
    resources:          Resources::ExtensionInfo.static_resources,
    resource_templates: Resources::ExtensionInfo.resource_templates
  )

  configure_server(server)

  mcp_log :info, 'server.build.complete',
          identity: Utils.summarize_identity(identity),
          tool_count: tools.size, registry_size: tool_registry.size,
          resource_count: server.resources.size
  server
end

.build_filtered_tool_list(keywords: []) ⇒ Object 



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# File 'lib/legion/mcp/server.rb', line 153

def build_filtered_tool_list(keywords: [])
  governed = ToolGovernance.filter_tools(tool_registry, @current_identity)
  tool_names = governed.map { |tc| tc.respond_to?(:tool_name) ? tc.tool_name : tc.name }
  ranked     = UsageFilter.ranked_tools(tool_names, keywords: keywords)
  result = ranked.filter_map do |name|
    governed.find do |tc|
      (tc.respond_to?(:tool_name) ? tc.tool_name : tc.name) == name
    end
  end
  log.debug("[mcp][server] action=build_filtered_tool_list tools_before=#{tool_registry.size} " \
            "governed=#{governed.size} tools_after=#{result.size} " \
            "identity=#{Utils.summarize_identity(@current_identity)} keywords=#{keywords.size}")
  result
end

.populate_embedding_index(embedder: EmbeddingIndex.default_embedder) ⇒ Object 



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# File 'lib/legion/mcp/server.rb', line 108

def populate_embedding_index(embedder: EmbeddingIndex.default_embedder)
  return unless embedder

  tool_data = ContextCompiler.tool_index.values
  EmbeddingIndex.build_from_tool_data(tool_data, embedder: embedder)
  mcp_log :info, 'server.embedding_index.populated', tool_count: tool_data.size
end

.rebuild_tool_registry ⇒ Object 



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# File 'lib/legion/mcp/server.rb', line 50

def rebuild_tool_registry
  log.debug("[mcp][server] action=rebuild_tool_registry mcp_specific=#{MCP_SPECIFIC_TOOLS.size}")
  @tool_registry_lock.synchronize do
    @tool_registry = Concurrent::Array.new(MCP_SPECIFIC_TOOLS)
    load_extension_tools
    DeferredRegistry.reset_cache! if defined?(DeferredRegistry) && DeferredRegistry.respond_to?(:reset_cache!)
    reset_caches!
  end
  log.debug("[mcp][server] action=rebuild_tool_registry.complete registry_size=#{tool_registry.size}")
end

.register_tool(tool_class) ⇒ Object 



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# File 'lib/legion/mcp/server.rb', line 61

def register_tool(tool_class)
  @tool_registry_lock.synchronize do
    return if tool_registry.any? { |tc| tc.tool_name == tool_class.tool_name }

    tool_registry << tool_class
    reset_caches!
    mcp_log :info, 'server.tool.registered',
            tool_name: tool_class.tool_name, registry_size: tool_registry.size
  end
end

.reset_caches! ⇒ Object 



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# File 'lib/legion/mcp/server.rb', line 81

def reset_caches!
  ContextCompiler.reset! if defined?(ContextCompiler)
  EmbeddingIndex.reset! if defined?(EmbeddingIndex) && EmbeddingIndex.respond_to?(:reset!)
end

.unregister_tool(tool_name) ⇒ Object 



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# File 'lib/legion/mcp/server.rb', line 72

def unregister_tool(tool_name)
  @tool_registry_lock.synchronize do
    tool_registry.reject! { |tc| tc.tool_name == tool_name }
    reset_caches!
    mcp_log :info, 'server.tool.unregistered',
            tool_name: tool_name, registry_size: tool_registry.size
  end
end

.wire_observer(data) ⇒ Object 



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# File 'lib/legion/mcp/server.rb', line 116

def wire_observer(data)
  return unless data[:method] == 'tools/call' && data[:tool_name]

  duration_ms = (data[:duration].to_f * 1000).to_i
  params_keys = data[:tool_arguments].respond_to?(:keys) ? data[:tool_arguments].keys : []
  success     = data[:error].nil?
  request_id  = Utils.request_id_from(data[:tool_arguments])

  mcp_log :info, 'server.tool_call.complete',
          request_id: request_id, tool_name: data[:tool_name],
          success: success, duration_ms: duration_ms,
          params_keys: params_keys, error: data[:error]

  Observer.record(
    tool_name:   data[:tool_name],
    duration_ms: duration_ms,
    success:     success,
    params_keys: params_keys,
    error:       data[:error]
  )

  # Pattern promotion for legion.do is handled inside DoAction itself
  # (which knows the actual resolved tool name). For other tools called
  # directly, we record the intent+result here if an intent is present.
  return if data[:tool_name] == 'legion.do'
  return unless data[:tool_arguments]&.dig(:intent)

  observer_args = {
    intent:    data[:tool_arguments][:intent],
    tool_name: data[:tool_name],
    success:   success
  }
  observer_args[:request_id] = request_id if request_id

  Observer.record_intent_with_result(**observer_args)
end