Class: Rubino::Context::PromptAssembler

Inherits:
Object
  • Object
show all
Defined in:
lib/rubino/context/prompt_assembler.rb

Overview

Assembles the complete prompt from all context sources. Returns the message array (system + summary + history) for LLM submission.

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(session:, memory_context:, config:, agent_definition: nil, ignore_rules: false) ⇒ PromptAssembler

Returns a new instance of PromptAssembler.



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# File 'lib/rubino/context/prompt_assembler.rb', line 46

def initialize(session:, memory_context:, config:, agent_definition: nil,
               ignore_rules: false)
  @session = session
  @memory_context = memory_context
  @config = config
  @agent_definition = agent_definition
  # --ignore-rules suppresses project-context discovery
  # (AGENTS.md/CLAUDE.md/.rubino.md/.cursorrules). The flag is threaded
  # from Lifecycle so the CLI option genuinely skips discovery (#47), not
  # just the trust gate.
  @ignore_rules = ignore_rules
  @message_store = Session::Store.new
end

Class Method Details

.reset_all_snapshots! ⇒ Object

Test/teardown hook. Not part of the public API.



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# File 'lib/rubino/context/prompt_assembler.rb', line 41

def reset_all_snapshots!
  @snapshots_mutex.synchronize { @snapshots.clear }
end

.reset_snapshot!(session_id) ⇒ Object

Drops the cached snapshot for a session so the next assembly captures fresh memory state. Use this when a tool call must influence the very next turn (trade-off: the freeze stops protecting against same-turn poisoning).



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# File 'lib/rubino/context/prompt_assembler.rb', line 36

def reset_snapshot!(session_id)
  @snapshots_mutex.synchronize { @snapshots.delete(session_id) }
end

.snapshot_for(session_id) ⇒ Object

Returns the cached snapshot for a session, computing it via the supplied block on first access. The block receives no args and must return the memory-context hash to freeze.



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# File 'lib/rubino/context/prompt_assembler.rb', line 26

def snapshot_for(session_id)
  @snapshots_mutex.synchronize do
    @snapshots[session_id] ||= yield
  end
end

Instance Method Details

#build ⇒ Object

Builds and returns the full message array for LLM submission



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# File 'lib/rubino/context/prompt_assembler.rb', line 61

def build
  messages = []

  # Single system message. The content is split into a STABLE PREFIX
  # (identity / product / env / user-profile snapshot / skills / project
  # context) and a VOLATILE TAIL (freshly-retrieved relevant-memories +
  # the post-compaction session-summary). The prefix carries the prompt-
  # cache breakpoint (#311); the tail — which can change turn-to-turn —
  # sits AFTER it so the cached bytes stay byte-stable. Both regions live
  # in ONE role:"system" entry (#253), built as a Content::Raw array of
  # text blocks when caching is on, or a plain joined String otherwise.
  messages << { role: "system", content: system_content }

  # Conversation history. Repair tool pairing across the FULL list before
  # mapping to wire format — this is the defensive "net" that recovers
  # sessions already corrupted by the historical metadata-dropping bug in
  # compaction/fork (those rows exist in prod). Mirrors Claude Code's
  # pre-call sanitization: never emit an orphan tool block that 400s a
  # strict provider. Conservative by design — when in doubt, keep.
  history = repair_tool_pairs(@message_store.for_session(@session[:id]))
  history.each do |msg|
    messages << msg.to_context
  end

  messages
end