- New ask_user core tool: mid-turn user question with option picking,
refusing cleanly in autonomous mode, for background workers, and
without a tty; system prompt points at it instead of prose questions.
- Structural loop control for prompt-JSON CLI backends (opencode,
grok, claude, codex, gemini): shared cli_json_turn repairs a
missing JSON envelope exactly once, then accepts prose; prompt
contract hardened against narrate-without-calling.
- research/agentic-tool-loop-design: 74 sources plus 2 conclusions
backing the loop-control decisions; INDEX updated to 6 subjects.
