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Class: Kward::Conversation

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

Overview

Mutable transcript and runtime context for one agent session.

Conversation owns message ordering, system prompt refresh, read-before-write state, memory prompt context, and persistence hooks. It intentionally stores plain hashes because provider payload builders, session JSONL files, and RPC normalizers all share the same transcript shape. Use MessageAccess when reading messages so symbol/string key and legacy field compatibility stays in one place.

Frontends should not mutate messages directly after attaching a SessionStore::Session; use append/compact helpers so persistence callbacks run and session trees stay consistent.

Constant Summary collapse

DEFAULT_SYSTEM_MESSAGE = 
Object.new.freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(system_message: DEFAULT_SYSTEM_MESSAGE, messages: [], read_paths: [], on_append: nil, on_compact: nil, on_tool_execution: nil, on_runtime_update: nil, workspace_root: Dir.pwd, compaction_system_message: DEFAULT_SYSTEM_MESSAGE, provider: nil, model: nil, reasoning_effort: nil, memory_context: nil, session_memories: [], last_memory_retrieval: nil, plugin_registry: nil) ⇒ Conversation

Returns a new instance of Conversation.



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# File 'lib/kward/conversation.rb', line 67

def initialize(system_message: DEFAULT_SYSTEM_MESSAGE, messages: [], read_paths: [], on_append: nil, on_compact: nil, on_tool_execution: nil, on_runtime_update: nil, workspace_root: Dir.pwd, compaction_system_message: DEFAULT_SYSTEM_MESSAGE, provider: nil, model: nil, reasoning_effort: nil, memory_context: nil, session_memories: [], last_memory_retrieval: nil, plugin_registry: nil)
  @workspace_root = ConfigFiles.canonical_workspace_root(workspace_root)
  @provider = provider
  @model = model
  @reasoning_effort = reasoning_effort
  @plugin_registry = plugin_registry
  @messages = []
  restored_system_message, transcript_messages = split_system_message(messages)
  if system_message.equal?(DEFAULT_SYSTEM_MESSAGE)
    if restored_system_message
      system_message = restored_system_message
    else
      @last_plugin_prompt_context = plugin_prompt_context
      system_message = Prompts.system_message(workspace_root: @workspace_root, model: @model, reasoning_effort: @reasoning_effort, now: prompt_time, memory_context: memory_context, plugin_context: @last_plugin_prompt_context)
    end
  end
  @system_message = system_message
  @system_message_enabled = !@system_message.nil?
  if compaction_system_message.equal?(DEFAULT_SYSTEM_MESSAGE)
    compaction_system_message = @system_message_enabled ? Prompts.system_message(workspace_root: @workspace_root, include_workspace_personality: false, model: @model, reasoning_effort: @reasoning_effort, now: prompt_time) : nil
  end
  @compaction_system_message = compaction_system_message
  @workspace_agents_mtime = workspace_agents_mtime
  @last_entry_compaction = false
  @memory_context = memory_context
  @session_memories = Array(session_memories)
  @last_memory_retrieval = last_memory_retrieval
  @tool_output_artifacts = {}
  @context_budget_meter = ContextBudgetMeter.new
  @messages.concat(transcript_messages)
  @read_paths = Set.new(read_paths)
  @on_append = on_append
  @on_compact = on_compact
  @on_tool_execution = on_tool_execution
  @on_runtime_update = on_runtime_update
  @on_system_message_change = nil
end

Instance Attribute Details

#compaction_system_message ⇒ Hash? (readonly)

Returns system prompt used when summarizing old context.

Returns:

  • (Hash, nil) —

    system prompt used when summarizing old context



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# File 'lib/kward/conversation.rb', line 35

def compaction_system_message
  @compaction_system_message
end

#context_budget_meter ⇒ ContextBudgetMeter (readonly)

Returns runtime context savings for this conversation.

Returns:



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# File 'lib/kward/conversation.rb', line 65

def context_budget_meter
  @context_budget_meter
end

#last_memory_retrieval ⇒ Hash?

Returns metadata for the last memory retrieval attached to the session.

Returns:

  • (Hash, nil) —

    metadata for the last memory retrieval attached to the session



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# File 'lib/kward/conversation.rb', line 57

def last_memory_retrieval
  @last_memory_retrieval
end

#last_plugin_prompt_context ⇒ String? (readonly)

Returns plugin prompt context used in the current system prompt.

Returns:

  • (String, nil) —

    plugin prompt context used in the current system prompt



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# File 'lib/kward/conversation.rb', line 61

def last_plugin_prompt_context
  @last_plugin_prompt_context
end

#memory_context ⇒ String?

Returns memory prompt context injected into refreshed system messages.

Returns:

  • (String, nil) —

    memory prompt context injected into refreshed system messages



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# File 'lib/kward/conversation.rb', line 55

def memory_context
  @memory_context
end

#messages ⇒ Array<Hash> (readonly)

Returns ordered durable transcript entries, excluding runtime system prompt state.

Returns:

  • (Array<Hash>) —

    ordered durable transcript entries, excluding runtime system prompt state



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# File 'lib/kward/conversation.rb', line 27

def messages
  @messages
end

#model ⇒ String? (readonly)

Returns model id captured for session/runtime prompts.

Returns:

  • (String, nil) —

    model id captured for session/runtime prompts



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# File 'lib/kward/conversation.rb', line 39

def model
  @model
end

#on_append ⇒ Proc?

Returns persistence callback invoked after appending a message.

Returns:

  • (Proc, nil) —

    persistence callback invoked after appending a message



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# File 'lib/kward/conversation.rb', line 45

def on_append
  @on_append
end

#on_compact ⇒ Proc?

Returns persistence callback invoked after compaction replaces history.

Returns:

  • (Proc, nil) —

    persistence callback invoked after compaction replaces history



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# File 'lib/kward/conversation.rb', line 47

def on_compact
  @on_compact
end

#on_runtime_update ⇒ Proc?

Returns callback invoked when runtime metadata should be persisted.

Returns:

  • (Proc, nil) —

    callback invoked when runtime metadata should be persisted



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# File 'lib/kward/conversation.rb', line 51

def on_runtime_update
  @on_runtime_update
end

#on_system_message_change ⇒ Proc?

Returns callback invoked when the system prompt runtime state changes.

Returns:

  • (Proc, nil) —

    callback invoked when the system prompt runtime state changes



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# File 'lib/kward/conversation.rb', line 53

def on_system_message_change
  @on_system_message_change
end

#on_tool_execution ⇒ Proc?

Returns callback invoked when a tool execution record should be persisted.

Returns:

  • (Proc, nil) —

    callback invoked when a tool execution record should be persisted



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# File 'lib/kward/conversation.rb', line 49

def on_tool_execution
  @on_tool_execution
end

#plugin_registry ⇒ PluginRegistry?

Returns registry used to collect plugin prompt context.

Returns:

  • (PluginRegistry, nil) —

    registry used to collect plugin prompt context



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# File 'lib/kward/conversation.rb', line 59

def plugin_registry
  @plugin_registry
end

#provider ⇒ String? (readonly)

Returns provider captured for session/runtime prompts.

Returns:

  • (String, nil) —

    provider captured for session/runtime prompts



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# File 'lib/kward/conversation.rb', line 37

def provider
  @provider
end

#read_paths ⇒ Set<String> (readonly)

Returns resolved paths read by file tools during the active context.

Returns:

  • (Set<String>) —

    resolved paths read by file tools during the active context



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# File 'lib/kward/conversation.rb', line 31

def read_paths
  @read_paths
end

#reasoning_effort ⇒ String? (readonly)

Returns reasoning effort captured for session/runtime prompts.

Returns:

  • (String, nil) —

    reasoning effort captured for session/runtime prompts



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# File 'lib/kward/conversation.rb', line 41

def reasoning_effort
  @reasoning_effort
end

#session_memories ⇒ Array<Hash> (readonly)

Returns memories scoped to this conversation session.

Returns:

  • (Array<Hash>) —

    memories scoped to this conversation session



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# File 'lib/kward/conversation.rb', line 43

def session_memories
  @session_memories
end

#system_message ⇒ Hash? (readonly)

Returns current system prompt included when building provider request context.

Returns:

  • (Hash, nil) —

    current system prompt included when building provider request context



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# File 'lib/kward/conversation.rb', line 29

def system_message
  @system_message
end

#tool_output_artifacts ⇒ Hash (readonly)

Returns original large tool outputs retained outside model context.

Returns:

  • (Hash) —

    original large tool outputs retained outside model context



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# File 'lib/kward/conversation.rb', line 63

def tool_output_artifacts
  @tool_output_artifacts
end

#workspace_root ⇒ String (readonly)

Returns canonical workspace root used for prompts and file guardrails.

Returns:

  • (String) —

    canonical workspace root used for prompts and file guardrails



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# File 'lib/kward/conversation.rb', line 33

def workspace_root
  @workspace_root
end

Class Method Details

.normalize_tool_content(content) ⇒ Object

Tool results may arrive as ASCII-8BIT (BINARY) strings, e.g. from Net::HTTP response bodies or shell command output. When such a string is later concatenated with a UTF-8 string containing non-ASCII bytes (during compaction or JSON serialization), Ruby raises Encoding::CompatibilityError. Re-tag BINARY strings as UTF-8 when the bytes are valid UTF-8; otherwise scrub so the content is always serializable and concatenable.



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# File 'lib/kward/conversation.rb', line 137

def self.normalize_tool_content(content)
  return content unless content.is_a?(String) && content.encoding == Encoding::ASCII_8BIT

  probe = content.dup.force_encoding(Encoding::UTF_8)
  probe.valid_encoding? ? probe : probe.scrub
end

.tool_output_artifact_id(tool_name:, content:) ⇒ Object 



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# File 'lib/kward/conversation.rb', line 169

def self.tool_output_artifact_id(tool_name:, content:)
  digest = Digest::SHA256.hexdigest("#{tool_name}\0#{content}")[0, 16]
  "toolout_#{digest}"
end

Instance Method Details

#append_assistant(message) ⇒ Object 



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# File 'lib/kward/conversation.rb', line 116

def append_assistant(message)
  message = { role: "assistant", content: message } if message.is_a?(String)
  append_message(message)
end

#append_tool(tool_call_id:, name:, content:) ⇒ Object 



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# File 'lib/kward/conversation.rb', line 121

def append_tool(tool_call_id:, name:, content:)
  append_message({
    role: "tool",
    tool_call_id: tool_call_id,
    name: name,
    content: self.class.normalize_tool_content(content)
  })
end

#append_tool_execution(tool_call:, content:) ⇒ Object 



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# File 'lib/kward/conversation.rb', line 144

def append_tool_execution(tool_call:, content:)
  @on_tool_execution&.call(tool_call, content)
end

#append_user(content, display_content: nil) ⇒ Object

Appends a user message and normalizes image attachment syntax.

display_content is transcript/UI text for cases where the model input is expanded, decorated, or contains encoded attachment content.



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# File 'lib/kward/conversation.rb', line 109

def append_user(content, display_content: nil)
  content = ImageAttachments.content_from_text(content) unless content.is_a?(Array)
  message = { role: "user", content: content }
  message[:display_content] = display_content.to_s unless display_content.nil?
  append_message(message)
end

#compact!(summary, compaction_summary: false, first_kept_entry_id: nil, tokens_before: nil, from_hook: false, details: {}, keep_messages: []) ⇒ Object

Replaces most transcript entries with a compaction summary and optional recent messages to keep.

Compaction clears read-before-write state because file contents observed before the summary may no longer be represented exactly in the active context. Callers that need file mutation after compaction should read files again through the normal tools.



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# File 'lib/kward/conversation.rb', line 230

def compact!(summary, compaction_summary: false, first_kept_entry_id: nil, tokens_before: nil, from_hook: false, details: {}, keep_messages: [])
  message = if compaction_summary
              { role: "compactionSummary", summary: summary.to_s }
            else
              { role: "assistant", content: summary.to_s }
            end
  if compaction_summary
    message[:first_kept_entry_id] = first_kept_entry_id if first_kept_entry_id
    message[:tokens_before] = tokens_before if tokens_before
    message[:from_hook] = from_hook
    message[:details] = details || {}
  end
  @messages = []
  @messages << message
  @messages.concat(Array(keep_messages))
  @read_paths.clear
  @last_entry_compaction = true
  @on_compact&.call(message)
  message
end

#context_messages ⇒ Array<Hash>

Returns provider request context: current system prompt plus durable transcript.

Returns:

  • (Array<Hash>) —

    provider request context: current system prompt plus durable transcript



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# File 'lib/kward/conversation.rb', line 175

def context_messages
  @system_message ? [@system_message] + @messages : @messages.dup
end

#last_entry_compaction? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/kward/conversation.rb', line 251

def last_entry_compaction?
  @last_entry_compaction
end

#last_file_change_result ⇒ Object 



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# File 'lib/kward/conversation.rb', line 259

def last_file_change_result
  @messages.select do |message|
    MessageAccess.role(message) == "tool" && ["write_file", "edit_file"].include?(MessageAccess.name(message))
  end.last
end

#mark_last_entry_compaction! ⇒ Object 



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# File 'lib/kward/conversation.rb', line 255

def mark_last_entry_compaction!
  @last_entry_compaction = true
end

#mark_read(path) ⇒ Object 



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# File 'lib/kward/conversation.rb', line 212

def mark_read(path)
  @read_paths << path
end

#persist_runtime_context! ⇒ Object 



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# File 'lib/kward/conversation.rb', line 204

def persist_runtime_context!
  @on_runtime_update&.call(provider: @provider, model: @model, reasoning_effort: @reasoning_effort)
end

#plugin_prompt_context ⇒ Object 



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# File 'lib/kward/conversation.rb', line 216

def plugin_prompt_context
  return nil unless plugin_registry

  context = PluginRegistry::Context.new(conversation: self, workspace_root: @workspace_root)
  plugin_registry.prompt_context(context)
end

#refresh_system_message! ⇒ Object

Rebuilds the system message from current config, memory, plugins, and workspace AGENTS.md state.

Conversations created with system_message: nil keep system prompts disabled; this preserves tests, compaction summaries, and imported transcripts that intentionally do not include runtime instructions.



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# File 'lib/kward/conversation.rb', line 185

def refresh_system_message!
  return nil unless @system_message_enabled

  @last_plugin_prompt_context = plugin_prompt_context
  replacement = Prompts.system_message(workspace_root: @workspace_root, model: @model, reasoning_effort: @reasoning_effort, now: prompt_time, memory_context: @memory_context, plugin_context: @last_plugin_prompt_context)
  @system_message = replacement
  @on_system_message_change&.call(replacement)
  @compaction_system_message = Prompts.system_message(workspace_root: @workspace_root, include_workspace_personality: false, model: @model, reasoning_effort: @reasoning_effort, now: prompt_time)
  @workspace_agents_mtime = workspace_agents_mtime
  replacement
end

#refresh_system_message_if_workspace_agents_changed! ⇒ Object 



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# File 'lib/kward/conversation.rb', line 208

def refresh_system_message_if_workspace_agents_changed!
  refresh_system_message! if @system_message_enabled && workspace_agents_mtime != @workspace_agents_mtime
end

#restore_tool_output_artifact(tool_name:, content:, created_at: nil) ⇒ Object 



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# File 'lib/kward/conversation.rb', line 156

def restore_tool_output_artifact(tool_name:, content:, created_at: nil)
  text = self.class.normalize_tool_content(content)
  id = tool_output_artifact_id_for(tool_name: tool_name, content: text)
  @tool_output_artifacts[id] = {
    id: id,
    tool_name: tool_name,
    content: text,
    bytes: text.bytesize,
    created_at: created_at || Time.now.utc
  }
  id
end

#store_tool_output_artifact(tool_name:, content:) ⇒ Object 



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# File 'lib/kward/conversation.rb', line 152

def store_tool_output_artifact(tool_name:, content:)
  restore_tool_output_artifact(tool_name: tool_name, content: content, created_at: Time.now.utc)
end

#tool_output_artifact_id_for(tool_name:, content:) ⇒ Object 



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# File 'lib/kward/conversation.rb', line 148

def tool_output_artifact_id_for(tool_name:, content:)
  self.class.tool_output_artifact_id(tool_name: tool_name, content: self.class.normalize_tool_content(content))
end

#update_runtime_context!(provider: nil, model:, reasoning_effort:, refresh: true) ⇒ Object 



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# File 'lib/kward/conversation.rb', line 197

def update_runtime_context!(provider: nil, model:, reasoning_effort:, refresh: true)
  @provider = provider unless provider.to_s.empty?
  @model = model
  @reasoning_effort = reasoning_effort
  refresh_system_message! if refresh
end