fix(phase): clarify insert preconditions and reject unsupported dry-run flag

get-shit-done/bin/lib/phase-command-router.cjs

@@ -33,6 +33,9 @@ function routePhaseCommand({ phase, args, cwd, raw, error }) {
     }
     phase.cmdPhaseAddBatch(cwd, descriptions, raw);
   } else if (subcommand === 'insert') {
+    if (args.includes('--dry-run')) {
+      error('phase insert does not support --dry-run');
+    }
     phase.cmdPhaseInsert(cwd, args[2], args.slice(3).join(' '), raw);
   } else if (subcommand === 'remove') {
     const forceFlag = args.includes('--force');

get-shit-done/bin/lib/phase.cjs

@@ -556,6 +556,10 @@ function cmdPhaseInsert(cwd, afterPhase, description, raw) {
     const afterPhaseEscaped = unpadded.replace(/\./g, '\\.');
     const targetPattern = new RegExp(`#{2,4}\\s*Phase\\s+0*${afterPhaseEscaped}:`, 'i');
     if (!targetPattern.test(content)) {
+      const checklistPattern = new RegExp(`-\\s*\\[[ x]\\]\\s*\\*\\*Phase\\s+0*${afterPhaseEscaped}:`, 'i');
+      if (checklistPattern.test(content)) {
+        error(`Phase ${afterPhase} exists in roadmap summary but is missing a detail section (### Phase ${afterPhase}: ...).`);
+      }
       error(`Phase ${afterPhase} not found in ROADMAP.md`);
     }
 

tests/phase.test.cjs

@@ -1237,6 +1237,28 @@ describe('phase insert command', () => {
     assert.ok(roadmap.includes('**Requirements**: TBD'), 'inserted phase entry should include Requirements TBD');
   });
 
+  test('reports actionable error for summary-only placeholder phase without detail section (#3098)', () => {
+    fs.writeFileSync(
+      path.join(tmpDir, '.planning', 'ROADMAP.md'),
+      `# Roadmap\n\n- [ ] **Phase 5: Placeholder**\n`
+    );
+
+    const result = runGsdTools('phase insert 5 Hotfix', tmpDir);
+    assert.ok(!result.success, 'should fail when phase is summary-only placeholder');
+    assert.ok(result.error.includes('missing a detail section'));
+  });
+
+  test('phase insert rejects unsupported --dry-run flag explicitly (#3098)', () => {
+    fs.writeFileSync(
+      path.join(tmpDir, '.planning', 'ROADMAP.md'),
+      `# Roadmap\n\n### Phase 1: Foundation\n**Goal:** Setup\n`
+    );
+
+    const result = runGsdTools('phase insert 1 Hotfix --dry-run', tmpDir);
+    assert.ok(!result.success, 'phase insert should reject unsupported --dry-run');
+    assert.ok(result.error.includes('does not support --dry-run'));
+  });
+
   test('handles #### heading depth from multi-milestone roadmaps', () => {
     fs.writeFileSync(
       path.join(tmpDir, '.planning', 'ROADMAP.md'),