diff --git a/commands/trekbrief.md b/commands/trekbrief.md
index f16d81f..acbb9c4 100644
--- a/commands/trekbrief.md
+++ b/commands/trekbrief.md
@@ -2,7 +2,6 @@
 name: trekbrief
 description: Interactive interview that produces a task brief with explicit research plan. Feeds /trekresearch and /trekplan. Optionally orchestrates the full pipeline end-to-end.
 argument-hint: "[--quick] <task description>"
-model: opus
 allowed-tools: Agent, Read, Glob, Grep, Write, Edit, Bash, AskUserQuestion
 ---
 
diff --git a/commands/trekcontinue.md b/commands/trekcontinue.md
index f71f947..7267fd9 100644
--- a/commands/trekcontinue.md
+++ b/commands/trekcontinue.md
@@ -2,7 +2,6 @@
 name: trekcontinue
 description: Resume the next session in a multi-session trekplan project. Reads .session-state.local.json and immediately begins the next session.
 argument-hint: "[<project-dir> | --help]"
-model: opus
 ---
 
 # Ultracontinue Local v1.0
diff --git a/commands/trekendsession.md b/commands/trekendsession.md
index 122fbb8..c8e0904 100644
--- a/commands/trekendsession.md
+++ b/commands/trekendsession.md
@@ -2,7 +2,6 @@
 name: trekendsession
 description: Mark the current session as complete and write session-state pointing at the next session. Helper for informal multi-session flows.
 argument-hint: "<next-brief-path> <next-label> | --help"
-model: opus
 ---
 
 # Voyage End-Session Local v1.0
diff --git a/commands/trekexecute.md b/commands/trekexecute.md
index fcd36d3..290cc3a 100644
--- a/commands/trekexecute.md
+++ b/commands/trekexecute.md
@@ -2,7 +2,6 @@
 name: trekexecute
 description: Disciplined plan executor — single-session or multi-session with parallel orchestration, failure recovery, and headless support
 argument-hint: "[--project <dir>] [--fg | --resume | --dry-run | --validate | --step N | --session N] [plan.md]"
-model: opus
 allowed-tools: Read, Write, Edit, Bash, Glob, Grep, AskUserQuestion
 disallowed-tools: Agent, TeamCreate
 ---
diff --git a/commands/trekplan.md b/commands/trekplan.md
index db8c61c..b2b737a 100644
--- a/commands/trekplan.md
+++ b/commands/trekplan.md
@@ -2,7 +2,6 @@
 name: trekplan
 description: Deep implementation planning from a task brief. Requires --brief or --project. Runs parallel specialized agents, optional external research, and adversarial review.
 argument-hint: "--brief <path> | --project <dir> [--fg | --quick | --research <brief> | --decompose <plan> | --export headless <plan>]"
-model: opus
 allowed-tools: Agent, Read, Glob, Grep, Write, Edit, Bash, AskUserQuestion, TaskCreate, TaskUpdate, TeamCreate, TeamDelete
 ---
 
diff --git a/commands/trekresearch.md b/commands/trekresearch.md
index 2b09864..a222708 100644
--- a/commands/trekresearch.md
+++ b/commands/trekresearch.md
@@ -2,7 +2,6 @@
 name: trekresearch
 description: Deep research combining local codebase analysis with external knowledge, producing structured research briefs with triangulation and confidence ratings
 argument-hint: "[--project <dir>] [--quick | --local | --external | --fg] [--engine swarm|deep-research] <research question>"
-model: opus
 allowed-tools: Agent, Read, Glob, Grep, Write, Edit, Bash, AskUserQuestion, WebSearch, WebFetch, mcp__tavily__tavily_search, mcp__tavily__tavily_research
 ---
 
diff --git a/commands/trekreview.md b/commands/trekreview.md
index 6f47d39..88d5e78 100644
--- a/commands/trekreview.md
+++ b/commands/trekreview.md
@@ -5,7 +5,6 @@ description: |
   review.md with severity-tagged findings (BLOCKER/MAJOR/MINOR/SUGGESTION)
   per Handover 6 (review → plan).
 argument-hint: "--project <dir> [--since <ref>] [--quick] [--validate] [--dry-run]"
-model: opus
 allowed-tools: Agent, Read, Glob, Grep, Write, Edit, Bash, AskUserQuestion
 ---
 
diff --git a/tests/lib/doc-consistency.test.mjs b/tests/lib/doc-consistency.test.mjs
index bb769c2..f54f588 100644
--- a/tests/lib/doc-consistency.test.mjs
+++ b/tests/lib/doc-consistency.test.mjs
@@ -1315,3 +1315,22 @@ for (const cmd of ['trekresearch', 'trekplan', 'trekreview', 'trekexecute']) {
     );
   });
 }
+
+// ── v5.9 (fable-tier step 7) — orchestrator model-pin ABSENCE pin ───────────
+// Command frontmatter deliberately omits `model:` — omission is the only
+// session-inheritance spelling documented by BOTH official surfaces (AP2-2:
+// the `inherit` literal is disputed between skills.md and the plugin-dev
+// command-frontmatter reference). Re-adding a pin locks the orchestrator to a
+// fixed model in every session; if deterministic pinning is ever wanted again,
+// do it consciously and update this pin's rationale.
+
+test('v5.9: no commands/*.md frontmatter carries a model: key (session inheritance by omission)', () => {
+  const offenders = [];
+  for (const f of listMd('commands')) {
+    const doc = parseDocument(read(`commands/${f}`));
+    const fm = doc.parsed && doc.parsed.frontmatter;
+    if (fm && 'model' in fm) offenders.push(f);
+  }
+  assert.deepEqual(offenders, [],
+    `command frontmatter must omit model: (orchestrator follows the session model); offenders: ${offenders.join(', ')}`);
+});