Mode detection and the interactive question tool

Interactive mode rules

• Pre-load the host's blocking question tool already in the current tool list before you ask any question. If the matching tool is listed but unloaded, use the host's tool-discovery primitive once at the start of the Interactive flow to load that capability — do not search for another host's tool name. Presence in the current tool list is proof; never call a user-facing question tool to discover whether it exists. The routing question, the per-finding walk-through, and the bulk-preview Proceed/Cancel question all depend on it.
• The numbered-list fallback applies only when the harness genuinely lacks a blocking question tool — no matching tool is in the current list, a real question call errors, or the runtime mode does not expose one. In those cases, present the options as a numbered list on the host's user-visible chat surface and wait for the reply. A question that calls for a user decision must either call the tool or fall back loudly. Rendering it as narrative text because the tool feels inconvenient, because the model is in report-formatting mode, or because the instruction was buried in a long skill is a bug.

Phase 0: Detect Mode

Arguments may contain a document path, a mode token, or both; both tokens together is not a conflict. Tokens starting with mode: are flags, not paths — strip them, and use any remaining token as the document path for Phase 1 (getting the document).

mode:non-interactive (or its deprecated alias mode:headless) sets non-interactive mode. This mode changes how the findings that were not applied are delivered; it does not change how findings are classified. Use the same judgment about which tier each finding belongs in:

• fixes that synthesis classifies as Apply are applied and reported in the change list (same as interactive)
• everything else — the grouped confirmation, decisions, and FYI observations — is returned as structured text with the original classifications intact, for the caller to handle. No blocking-question prompts, no interactive routing.
• proposed fixes and decisions that were not applied are also recorded in the document, per references/open-questions-defer.md, so they outlive this session, unless the request restricts edits to the document
• Phase 5 (routing) returns immediately with "Review complete" (no routing question, no terminal question)

Non-interactive argument contract: mode:non-interactive <document-path>, for example mode:non-interactive <path-to-doc>.{md,html}. mode:headless is a deprecated alias for the same contract.

Absent either token, run interactive, with the routing question, walk-through, and bulk-preview behaviors documented in references/walkthrough.md and references/bulk-preview.md.