--- description: Show Navigation Engine decision trace for last turn help_jtbd: "See why Larry recommended what he recommended." body_shape: F.1 layer: "none" layer_why: "Shows the Navigation Engine trace for the last turn; a pure diagnostic render of a decision already made, not itself an engineering rung." hitl_shape: "F.1" hitl_why: "It explains a decision and offers one next move to take." # Phase 267.3-06, ruled in 267.3-CLASSIFICATION.md (Row 10): first delivery at commands/explain-decision.md:61, a rendered audit trace of a PAST recommendation, read verbatim from a log rather than reasoned fresh. interactive_first_reward: "--none (diagnostic surface)" argument-hint: "[--last N] [--session SESSIONID]" serves_jtbd: ["audit-room"] teaching: "When Larry made a recommendation and you want to know why, /mos:explain-decision shows the Navigation Engine trace for the last turn. Every recommendation has a graph path behind it." disable-model-invocation: true allowed-tools: Bash(node *), AskUserQuestion # --- Phase 172-16 CIRS R1 WIRE (Canon Part 11; navigator-directed 2026-06-23) --- connector: connects_to_spine: true sensor_triggers: [] reach_id: context_block sub_mode: decision-explain framework: null posture: hold hierarchy_rank: 16 filing: memory_event_only plan_gated: false web_scope: null surface: F.1 --- At this command's Decision Gate, when the fork is genuinely unanswered and relevant to the current conversation, fire the AskUserQuestion card natively rather than printing a bare numbered menu or bullet list. Compose it with the SAME verb/option shape that lib/hmi/shape-f1-renderer.cjs (renderShapeF1) produces and that lib/hmi/selector-dispatcher.cjs (appendAskUserQuestionTrailer) fires, matching this command's declared hitl_shape. Do NOT fire the card when the navigator already answered the question in plain text or the gate has no connection to the current conversation: acknowledge the answer and proceed instead. Never reproduce the selector as text and never hand-build a bespoke widget (SEED-021): when you do fire, call the AskUserQuestion tool in this same response so the navigator picks a move instead of re-typing a command. Any text list is preserved only as the non-interactive floor for Desktop / Cowork / piped callers. # /mos:explain-decision User-facing audit surface for the Navigation Engine. Reads the decision trace JSON written each turn by the UserPromptSubmit hook (Plan 91-02) and renders a human-readable explanation of which signals contributed, which skill fired, what was suppressed, and what was offered. This is the answer to "Why did Larry do that?" ## Modes - `/mos:explain-decision` -- render the most recent decision (default). - `/mos:explain-decision --last 5` -- render the last N decisions in this session. - `/mos:explain-decision --session SESSIONID` -- render decisions from a specific session (cross-session audit). - `/mos:explain-decision --last 3 --session SESSIONID` -- combine both flags. ## Output shape Per-turn block contains: - Tier Mode (mode_a, mode_b, or tier_0) with a glyph classifier (check / warn / low). - BRAIN.md signal: version, staleness, stale_reason, weight_applied, sections_consumed. - RECOMMENDED marker: rendered, highest_confidence (Canon Part 3 Section 6 0.7 floor). - Five-Signal Triangulation: ICM scope, SQL signals, Feynman-MINTO health, BRAIN patterns, Intent + Persona. - Chosen rationale (the one-line "why this turn" string the engine emitted). - Routing source (legacy fallback, engine, or mixed) when Plan 91-03 routing fired. - Offer rendered (the exact "Offer:" line Larry surfaced) when Plan 91-04 produced one. ## Session resolution When `--session` is not supplied, the command resolves the active session in this order: 1. `CLAUDE_SESSION_ID` environment variable. 2. `.mindrian/current-session.json` pointer file. 3. Most-recent `.mindrian/decision-traces/*.json` by mtime. ## Graceful fallback The command never throws. It always exits 0 with one of: - A rendered trace block (happy path). - "No decisions recorded for this session." advisory (no trace file yet). - "Decision trace file could not be parsed." advisory (malformed JSON). - "No active room found." advisory (registry missing or no active room). ## Canon references - **Canon Part 3 (Tri-Context Decision Gate, Section 8 trace contract):** every Decision Gate must be explainable. This command IS the audit surface that satisfies that obligation. - **Canon Part 4 (Every Choice Is Graph Data):** the command READS from the graph-data surface (decision-traces/*.json). It is a pure audit lens; never writes back. - **Canon Part 8 (Graph Boundary):** zero network surface. Reads only LOCAL `.mindrian/decision-traces/`. No Brain calls, no fetch, no shell-out. ## Invocation Run the dispatcher via Bash: ```bash node ${CLAUDE_PLUGIN_ROOT}/scripts/explain-decision-command.cjs $ARGUMENTS ``` ## Examples ``` /mos:explain-decision /mos:explain-decision --last 3 /mos:explain-decision --session abc123def456 /mos:explain-decision --last 5 --session abc123def456 ``` ## Exit codes | Exit | Meaning | | --- | --- | | 0 | Always (advisory paths included). The command is a read-only audit surface and never errors. | ## Loop-fires assertion surface (Phase 146) `/mos:explain-decision` is the loop-fires assertion surface: the per-turn trace it renders carries the `routing_source` (legacy vs engine), the fired `reach_id`, and the posture -- the exact signals that prove the loop FIRED on a turn. The Phase 146 loop-fires gate (the milestone gate that certifies the loop fires across the full connector surface) is hosted at `doctor --dogfood-acceptance` (the 5 ACPT dogfood drivers with their own exit-code contract) and at `tests/run-all-146.sh` (the 5 ACPT drivers plus the re-run of run-all-144/1441/145 for full-surface certification). Exit 0 there means the milestone ships as "Larry Reaches". This command does not host the gate; it is the read-only audit surface for inspecting an individual fired turn. ## Cross-surface adaptation - **CLI:** full power. Shape of output is plain text suitable for terminal rendering. - **Desktop:** the same slash command runs when the plugin is connected. Larry may narrate the rendered trace conversationally; the underlying dispatcher is identical. - **Cowork:** same as CLI. Each collaborator's session has its own trace file; `--session` allows cross-user audit when collaborators share trace files via the room.