ci: guard artifact paths on every command surface, not only Claude Code

validate-artifact-paths.js exists to stop the #93 class of drift, where a
producer moves SPEC.md or tasks/plan.md and a consumer keeps reading the
old path. It guarded only the .claude/commands copies plus two skills and
two docs. The same commands ship twice more — .gemini/commands/*.toml and
the root commands/*.toml — each with its own prompt body that names the
same artifacts, and validate-commands.js deliberately compares only
descriptions, so a drift on either TOML surface merged green while the
Claude Code copy stayed canonical. docs/copilot-setup.md was also unguarded
although its prompt-file aliases spell the artifact paths out for users.

Add the six TOML producers and consumers and the Copilot doc to
GUARDED_FILES, grouped by surface. Rule, allowlist and regex are unchanged.
Four new tests cover a Gemini producer drifting alone, a root TOML consumer
drifting alone, all three surfaces agreeing, and the Copilot doc. All seven
newly guarded files already use canonical paths: 14 files checked, 0 errors.

scripts/validate-artifact-paths-test.js

@@ -114,3 +114,66 @@ test('skips guarded files that do not exist', () => {
   assert.equal(result.status, 0, result.stdout + result.stderr);
   assert.match(result.stdout, /1 files checked — 0 error\(s\) — PASSED/);
 });
+
+// ─── Every command surface is guarded, not only the Claude Code copy ────────
+//
+// The Gemini and root TOML command sets carry their own prompt bodies, which
+// validate-commands.js deliberately does not compare. A producer can therefore
+// drift on one surface while `.claude/commands/` stays correct, and before
+// these files were guarded that drift merged silently.
+
+test('fails when a Gemini command drifts while the Claude Code copy stays canonical', () => {
+  const root = makeSandbox();
+  writeFile(root, '.claude/commands/spec.md', 'Save the spec as `SPEC.md` in the project root.\n');
+  writeFile(
+    root,
+    '.gemini/commands/spec.toml',
+    'description = "Start spec-driven development"\n\nprompt = """\nSave the spec to `docs/features/[feature-name]/spec.md`.\n"""\n',
+  );
+
+  const result = run(root);
+
+  assert.equal(result.status, 1, result.stdout + result.stderr);
+  assert.match(result.stdout, /\.gemini\/commands\/spec\.toml/);
+  assert.match(result.stdout, /L4: docs\/features\/\[feature-name\]\/spec\.md/);
+  assert.match(result.stdout, /1 error\(s\) — FAILED/);
+});
+
+test('fails when a root TOML consumer drifts away from the producers', () => {
+  const root = makeSandbox();
+  writeFile(root, 'commands/planning.toml', 'prompt = """\nSave the plan to `tasks/plan.md` and the task list to `tasks/todo.md`.\n"""\n');
+  writeFile(root, 'commands/build.toml', 'prompt = """\nRead the plan from `planning/plan.md` before starting.\n"""\n');
+
+  const result = run(root);
+
+  assert.equal(result.status, 1, result.stdout + result.stderr);
+  assert.match(result.stdout, /commands\/build\.toml/);
+  assert.match(result.stdout, /planning\/plan\.md/);
+});
+
+test('passes when all three command surfaces agree on the canonical paths', () => {
+  const root = makeSandbox();
+  for (const dir of ['.claude/commands', '.gemini/commands', 'commands']) {
+    const ext = dir === '.claude/commands' ? 'md' : 'toml';
+    const planStem = dir === '.claude/commands' ? 'plan' : 'planning';
+    writeFile(root, `${dir}/spec.${ext}`, 'Save the spec as `SPEC.md`.\n');
+    writeFile(root, `${dir}/${planStem}.${ext}`, 'Save to `tasks/plan.md` and `tasks/todo.md`.\n');
+    writeFile(root, `${dir}/build.${ext}`, 'Require `SPEC.md` or `docs/SPEC.md`, and `tasks/plan.md`.\n');
+  }
+
+  const result = run(root);
+
+  assert.equal(result.status, 0, result.stdout + result.stderr);
+  assert.match(result.stdout, /9 files checked — 0 error\(s\) — PASSED/);
+});
+
+test('guards the Copilot setup doc, whose prompt-file aliases name the artifacts', () => {
+  const root = makeSandbox();
+  writeFile(root, 'docs/copilot-setup.md', 'Read `tasks/plan.md`, then write the spec to `specs/[name]/spec.md`.\n');
+
+  const result = run(root);
+
+  assert.equal(result.status, 1, result.stdout + result.stderr);
+  assert.match(result.stdout, /docs\/copilot-setup\.md/);
+  assert.match(result.stdout, /specs\/\[name\]\/spec\.md/);
+});

scripts/validate-artifact-paths.js

@@ -41,14 +41,31 @@ const ARTIFACT_ALLOWLIST = new Set([
 
 // The files that make up the spec -> plan -> build pipeline. Absent files are
 // skipped, not failed: this validator checks path consistency, not presence.
+//
+// The command bodies exist once per host surface (validate-commands.js checks
+// that the three sets stay in step on descriptions, but their prompt bodies
+// are allowed to differ), so a producer or consumer can drift on one surface
+// while the Claude Code copy stays correct. Every surface is guarded here.
 const GUARDED_FILES = [
+  // Claude Code commands
   '.claude/commands/spec.md',
   '.claude/commands/plan.md',
   '.claude/commands/build.md',
+  // Gemini CLI commands
+  '.gemini/commands/spec.toml',
+  '.gemini/commands/planning.toml',
+  '.gemini/commands/build.toml',
+  // Root command set (Antigravity, Codex, and other TOML-based hosts)
+  'commands/spec.toml',
+  'commands/planning.toml',
+  'commands/build.toml',
+  // Skills the commands invoke
   'skills/spec-driven-development/SKILL.md',
   'skills/planning-and-task-breakdown/SKILL.md',
+  // Docs that tell users where the artifacts live
   'docs/getting-started.md',
   'docs/adoption-guide.md',
+  'docs/copilot-setup.md', // its prompt-file aliases name the artifacts directly
 ];
 
 // Matches a path-like token ending in a spec/plan/todo artifact filename,