diff --git a/agents/gsd-executor.md b/agents/gsd-executor.md
index cff36f375..82b35a7f6 100644
--- a/agents/gsd-executor.md
+++ b/agents/gsd-executor.md
@@ -362,7 +362,16 @@ git commit -m "{type}({phase}-{plan}): {concise task description}
 - **Single-repo:** `TASK_COMMIT=$(git rev-parse --short HEAD)` — track for SUMMARY.
 - **Multi-repo (sub_repos):** Extract hashes from `commit-to-subrepo` JSON output (`repos.{name}.hash`). Record all hashes for SUMMARY (e.g., `backend@abc1234, frontend@def5678`).
 
-**6. Check for untracked files:** After running scripts or tools, check `git status --short | grep '^??'`. For any new untracked files: commit if intentional, add to `.gitignore` if generated/runtime output. Never leave generated files untracked.
+**6. Post-commit deletion check:** After recording the hash, verify the commit did not accidentally delete tracked files:
+```bash
+DELETIONS=$(git diff --diff-filter=D --name-only HEAD~1 HEAD 2>/dev/null || true)
+if [ -n "$DELETIONS" ]; then
+  echo "WARNING: Commit includes file deletions: $DELETIONS"
+fi
+```
+Intentional deletions (e.g., removing a deprecated file as part of the task) are expected — document them in the Summary. Unexpected deletions are a Rule 1 bug: revert and fix before proceeding.
+
+**7. Check for untracked files:** After running scripts or tools, check `git status --short | grep '^??'`. For any new untracked files: commit if intentional, add to `.gitignore` if generated/runtime output. Never leave generated files untracked.
 </task_commit_protocol>
 
 <summary_creation>
diff --git a/get-shit-done/workflows/execute-phase.md b/get-shit-done/workflows/execute-phase.md
index 0605361ac..043d27cb4 100644
--- a/get-shit-done/workflows/execute-phase.md
+++ b/get-shit-done/workflows/execute-phase.md
@@ -510,6 +510,15 @@ Execute each selected wave in sequence. Within a wave: parallel if `PARALLELIZAT
        # Snapshot list of files on main BEFORE merge to detect resurrections
        PRE_MERGE_FILES=$(git ls-files .planning/)
 
+       # Pre-merge deletion check: warn if the worktree branch deletes tracked files
+       DELETIONS=$(git diff --diff-filter=D --name-only HEAD..."$WT_BRANCH" 2>/dev/null || true)
+       if [ -n "$DELETIONS" ]; then
+         echo "BLOCKED: Worktree branch $WT_BRANCH contains file deletions: $DELETIONS"
+         echo "Review these deletions before merging. If intentional, remove this guard and re-run."
+         rm -f "$STATE_BACKUP" "$ROADMAP_BACKUP"
+         continue
+       fi
+
        # Merge the worktree branch into the current branch
        git merge "$WT_BRANCH" --no-edit -m "chore: merge executor worktree ($WT_BRANCH)" 2>&1 || {
          echo "⚠ Merge conflict from worktree $WT_BRANCH — resolve manually"
diff --git a/tests/worktree-safety.test.cjs b/tests/worktree-safety.test.cjs
new file mode 100644
index 000000000..72bf18e8e
--- /dev/null
+++ b/tests/worktree-safety.test.cjs
@@ -0,0 +1,113 @@
+/**
+ * Worktree commit safety hardening tests (#1977)
+ *
+ * Three checks:
+ * 1. worktree_branch_check in execute-plan.md is NOT labeled as Windows-only
+ *    (the bug affects all platforms — no platform qualifier should narrow the fix)
+ * 2. gsd-executor.md task_commit_protocol includes post-commit deletion verification
+ *    (using --diff-filter=D to catch accidental file deletions per task)
+ * 3. execute-phase.md worktree merge section includes pre-merge deletion check
+ *    (using --diff-filter=D to block merges that would delete tracked files)
+ */
+
+'use strict';
+
+const { describe, test } = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('fs');
+const path = require('path');
+
+const EXECUTE_PLAN_PATH = path.join(__dirname, '..', 'get-shit-done', 'workflows', 'execute-plan.md');
+const EXECUTOR_AGENT_PATH = path.join(__dirname, '..', 'agents', 'gsd-executor.md');
+const EXECUTE_PHASE_PATH = path.join(__dirname, '..', 'get-shit-done', 'workflows', 'execute-phase.md');
+
+describe('worktree commit safety hardening (#1977)', () => {
+  test('execute-plan worktree_branch_check has no Windows-only platform qualifier', () => {
+    const content = fs.readFileSync(EXECUTE_PLAN_PATH, 'utf-8');
+
+    // The worktree_branch_check block must exist
+    assert.ok(
+      content.includes('worktree_branch_check'),
+      'execute-plan.md must contain a worktree_branch_check block'
+    );
+
+    // Search the whole file for any Windows-only qualifier near worktree_branch_check
+    // Must NOT say "Windows-only" or restrict the check to Windows
+    const hasWindowsOnlyQualifier = (
+      /Windows.only/i.test(content) ||
+      /affects Windows only/i.test(content) ||
+      /only on Windows/i.test(content) ||
+      /Windows-specific/i.test(content)
+    );
+    assert.ok(
+      !hasWindowsOnlyQualifier,
+      'worktree_branch_check must not be labeled as Windows-only — the bug affects all platforms'
+    );
+
+    // Must indicate the fix is universal (affects all platforms or similar)
+    // The description must exist somewhere in the file
+    const isUniversal = (
+      /affects all platforms/i.test(content) ||
+      /all platforms/i.test(content) ||
+      /cross.platform/i.test(content)
+    );
+    assert.ok(
+      isUniversal,
+      'worktree_branch_check description must indicate the fix applies to all platforms'
+    );
+  });
+
+  test('gsd-executor.md task_commit_protocol includes post-commit deletion verification', () => {
+    const content = fs.readFileSync(EXECUTOR_AGENT_PATH, 'utf-8');
+
+    // Must contain --diff-filter=D deletion check
+    assert.ok(
+      content.includes('--diff-filter=D'),
+      'gsd-executor.md must include --diff-filter=D deletion verification after each task commit'
+    );
+
+    // Must include a WARNING or notice about deletions
+    assert.ok(
+      content.includes('WARNING') || content.includes('DELETIONS'),
+      'gsd-executor.md must warn when a commit includes file deletions'
+    );
+  });
+
+  test('execute-phase.md worktree merge section includes pre-merge deletion check', () => {
+    const content = fs.readFileSync(EXECUTE_PHASE_PATH, 'utf-8');
+
+    // The merge section must exist
+    const mergeIdx = content.indexOf('git merge');
+    assert.ok(mergeIdx > -1, 'execute-phase.md must contain a git merge operation');
+
+    // Find the window before the merge command to check for pre-merge deletion detection
+    // Look broadly for --diff-filter=D in the worktree cleanup section
+    const worktreeCleanupStart = content.indexOf('Worktree cleanup');
+    assert.ok(
+      worktreeCleanupStart > -1,
+      'execute-phase.md must have a worktree cleanup section'
+    );
+
+    const cleanupSection = content.slice(worktreeCleanupStart);
+
+    // Must include --diff-filter=D for deletion detection
+    assert.ok(
+      cleanupSection.includes('--diff-filter=D'),
+      'execute-phase.md worktree merge section must include --diff-filter=D to check for deletions before merge'
+    );
+
+    // The deletion check must appear BEFORE the git merge call within the cleanup section
+    const deletionCheckIdx = cleanupSection.indexOf('--diff-filter=D');
+    const gitMergeIdx = cleanupSection.indexOf('git merge');
+    assert.ok(
+      deletionCheckIdx < gitMergeIdx,
+      'deletion check (--diff-filter=D) must appear before git merge in the worktree cleanup section'
+    );
+
+    // Must have a BLOCKED or warning message for when deletions are found
+    assert.ok(
+      cleanupSection.includes('BLOCKED') || cleanupSection.includes('DELETIONS') || cleanupSection.includes('deletion'),
+      'execute-phase.md must warn or block when the worktree branch contains file deletions'
+    );
+  });
+});