diff --git a/.changeset/kind-sloths-climb.md b/.changeset/kind-sloths-climb.md
new file mode 100644
index 000000000..5269c7130
--- /dev/null
+++ b/.changeset/kind-sloths-climb.md
@@ -0,0 +1,5 @@
+---
+type: Fixed
+pr: 3093
+---
+**`docs/json-errors.md` now documents the ExitError plain-text carve-out** — the page previously claimed every CLI error emits a structured JSON envelope on stderr, but usage errors (ExitError) intentionally emit plain text with their own exit code. The structured-envelope guidance is now scoped to non-usage failures, with the carve-out stated explicitly and a characterization test pinning both paths. (#2979)
diff --git a/.changeset/lucky-tunas-leap.md b/.changeset/lucky-tunas-leap.md
new file mode 100644
index 000000000..c548f2d6d
--- /dev/null
+++ b/.changeset/lucky-tunas-leap.md
@@ -0,0 +1,5 @@
+---
+type: Fixed
+pr: 3091
+---
+**`progress.completed_plans` no longer stays pinned after a gap-closure cycle** — when plan-phase re-planned a phase and added gap-closure plans, `total_plans` corrected upward but `completed_plans` was restored to its pre-growth value, so STATE.md showed `completed_plans < total_plans` permanently even after every plan (including the gap-closure ones) was summarized. `completed_plans` and `completed_phases` now ratchet up to the disk-derived count under the plan-phase progress opt-in (never deriving downward, preserving the curated-progress ratchet for unrelated edits). (#2969)
diff --git a/.changeset/proud-eagles-chatter.md b/.changeset/proud-eagles-chatter.md
new file mode 100644
index 000000000..49f9b3016
--- /dev/null
+++ b/.changeset/proud-eagles-chatter.md
@@ -0,0 +1,5 @@
+---
+type: Fixed
+pr: 3097
+---
+**`/gsd` commands in Pi now display their output** — the command handler returned output as a bare string, which Pi's ExtensionAPI silently dropped. It now returns Pi's structured `{ content: [{ type: 'text', text }] }` display shape (matching the `gsd_invoke` tool's proven contract), so success output and error messages are visible. (#2991)
diff --git a/.changeset/proud-pumas-bark.md b/.changeset/proud-pumas-bark.md
new file mode 100644
index 000000000..1cbbe9665
--- /dev/null
+++ b/.changeset/proud-pumas-bark.md
@@ -0,0 +1,5 @@
+---
+type: Fixed
+pr: 3096
+---
+**`/gsd-code-review` no longer picks a wrong diff base from unanchored commit-message grep** — the diff-base fallback searched all commit messages for the bare phase number as a substring, matching version strings, dates, and issue refs, then took the oldest match. The grep is now anchored to the phase-mention convention (`Phase N` with a word boundary), so the fail-closed branch is reachable when no commit genuinely references the phase. (#2989)
diff --git a/.changeset/silly-moles-rally.md b/.changeset/silly-moles-rally.md
new file mode 100644
index 000000000..f1a88560b
--- /dev/null
+++ b/.changeset/silly-moles-rally.md
@@ -0,0 +1,5 @@
+---
+type: Fixed
+pr: 3092
+---
+**`roadmap validate` now performs real structural validation** — it previously returned `{"warnings":[]}` (exit 0) for every input including empty files, garbage text, and missing files, providing false assurance. It now checks file existence/readability, emptiness, frontmatter well-formedness, and the presence of at least one phase entry, exiting non-zero on any warning (per its documented contract). The existing opt-in milestone-prefix consistency check is preserved. (#2978)
diff --git a/.changeset/witty-yaks-munch.md b/.changeset/witty-yaks-munch.md
new file mode 100644
index 000000000..458bf18eb
--- /dev/null
+++ b/.changeset/witty-yaks-munch.md
@@ -0,0 +1,5 @@
+---
+type: Fixed
+pr: 3095
+---
+**Local `lint:changeset` and `lint:docs-required` now diff against `next` instead of `main`** — the local fallback was the release branch (`main`), which lags far behind the integration branch (`next`), so the lint always passed by finding fragments from other already-merged PRs in the oversized diff range. The local invocation now matches the base CI uses. (#2988)
diff --git a/docs/json-errors.md b/docs/json-errors.md
index c12c058c6..2da5a9869 100644
--- a/docs/json-errors.md
+++ b/docs/json-errors.md
@@ -2,11 +2,12 @@
 
 ## Overview
 
-`gsd-tools` supports a **JSON error mode** that emits all errors as structured
+`gsd-tools` supports a **JSON error mode** that emits most errors as structured
 JSON objects on stderr instead of free-form text.  This is the recommended
 surface for tests and tooling that need to assert on error types without
 grepping raw text (see `CONTRIBUTING.md` — "Prohibited: Raw Text Matching on
-Test Outputs").
+Test Outputs"). Usage errors are an intentional exception — see the
+`ExitError` carve-out below.
 
 ## Activating
 
@@ -37,6 +38,20 @@ Fields:
 | `reason`  | string  | Typed reason code from the taxonomy below. |
 | `message` | string  | Human-readable description (may change; do not assert on it). |
 
+### `ExitError` carve-out (plain text, not JSON)
+
+Usage errors and explicit exit-code signals take a **different path**: they
+throw `ExitError` (`src/cli-exit.cts`), which `runMain` catches *before* the
+JSON-envelope branch. An `ExitError` writes its `message` as **plain text**
+to stderr (not a JSON object) and exits with the error's own `code` (which
+may differ from 1). This is intentional — usage messages are operator-facing
+prose, not structured failures.
+
+If you are testing a usage/flag error, do **not** parse stderr as JSON;
+assert on the exit code and (if needed) the plain-text message. The
+"parse stderr as JSON" guidance below applies only to the structured-envelope
+branch (non-`ExitError` failures).
+
 ## Error code taxonomy
 
 Codes are frozen constants in `gsd-core/bin/lib/core.cjs` under
@@ -99,8 +114,9 @@ text (unstable).
 
 ## Writing tests
 
-Always parse stderr with `JSON.parse` and assert on typed fields.  Never use
-`.includes()`, `.match()`, or regex on the raw error string.
+For **non-usage** errors (the structured-envelope branch), parse stderr with
+`JSON.parse` and assert on typed fields.  Never use `.includes()`, `.match()`,
+or regex on the raw error string.
 
 ```js
 // CORRECT: parse then assert on typed field
diff --git a/gsd-core/workflows/code-review.md b/gsd-core/workflows/code-review.md
index b64264738..9adc0f639 100644
--- a/gsd-core/workflows/code-review.md
+++ b/gsd-core/workflows/code-review.md
@@ -236,8 +236,13 @@ Additionally, whenever a reliable diff base is available, cross-check the SUMMAR
 against the diff and warn about (then add) any changed files the SUMMARY extractor did not
 surface — so a partial SUMMARY result can no longer silently mask the rest of the phase.
 ```bash
-# Compute diff base from phase commits — fail closed if no reliable base found
-PHASE_COMMITS=$(git log --oneline --all --grep="${PADDED_PHASE}" --format="%H" 2>/dev/null)
+# Compute diff base from phase commits — fail closed if no reliable base found.
+# #2989: anchor the grep to the phase-mention convention ("Phase N" / "phase N"
+# with a word boundary) so a bare digit substring doesn't match version strings,
+# dates, issue refs, or other phases' numbers. With --extended-regexp, \b is
+# a word boundary. When no commit genuinely references the phase, this yields
+# empty and the fail-closed warning below actually fires.
+PHASE_COMMITS=$(git log --oneline --all --grep="[Pp]hase ${PADDED_PHASE}\b" --extended-regexp --format="%H" 2>/dev/null)
 DIFF_BASE=""
 if [ -n "$PHASE_COMMITS" ]; then
   DIFF_BASE=$(echo "$PHASE_COMMITS" | tail -1)^
diff --git a/pi/gsd.cjs b/pi/gsd.cjs
index c30bd738a..9a3fdc702 100644
--- a/pi/gsd.cjs
+++ b/pi/gsd.cjs
@@ -287,11 +287,16 @@ module.exports = function gsdPiExtension(pi) {
       try {
         ({ dispatchGsdCommand } = require(path.join(GSD_CORE, 'bin', 'lib', 'shell-command-projection.cjs')));
       } catch (e) {
-        return `GSD engine unavailable: ${e && e.message ? e.message : String(e)}`;
+        // #2991: return the structured { content } shape Pi's ExtensionAPI
+        // displays, not a bare string (which Pi silently drops).
+        return { content: [{ type: 'text', text: `GSD engine unavailable: ${e && e.message ? e.message : String(e)}` }] };
       }
       const result = dispatchGsdCommand({ family, subcommand, args: rest, cwd });
-      if (result.ok) return result.stdout;
-      return `GSD error: ${result.stderr || result.stdout || `dispatch failed (exit ${result.code})`}`;
+      // #2991: match gsd_invoke's proven output shape so Pi actually displays it.
+      const text = result.ok
+        ? result.stdout
+        : `GSD error: ${result.stderr || result.stdout || `dispatch failed (exit ${result.code})`}`;
+      return { content: [{ type: 'text', text }] };
     },
   });
 
diff --git a/scripts/changeset/lint.cjs b/scripts/changeset/lint.cjs
index 9fe975093..933d5fe55 100755
--- a/scripts/changeset/lint.cjs
+++ b/scripts/changeset/lint.cjs
@@ -12,6 +12,10 @@
  * Tests assert on the typed verdict, never on free text.
  */
 
+// #2988: the repo's integration/default branch — the base every PR targets.
+// Used as the local fallback when GITHUB_BASE_REF is unset (CI sets it).
+const DEFAULT_BASE = 'next';
+
 const LINT_REASON = Object.freeze({
   OK_FRAGMENT_PRESENT: 'ok_fragment_present',
   OK_OPT_OUT_LABEL: 'ok_opt_out_label',
@@ -80,7 +84,10 @@ function main() {
       labels = (event.pull_request?.labels || []).map((l) => l.name);
     } catch { /* fall through */ }
   }
-  const base = process.env.GITHUB_BASE_REF || 'main';
+  // #2988: local fallback must match the repo's integration branch (`next`),
+  // not the release branch (`main`). CI sets GITHUB_BASE_REF explicitly; the
+  // fallback only fires locally, where `next` is the base every PR targets.
+  const base = process.env.GITHUB_BASE_REF || DEFAULT_BASE;
   let changedFiles = [];
   try {
     // Use execFileSync with an argv array — the base ref is interpolated
@@ -145,4 +152,4 @@ function main() {
 
 if (require.main === module) runMain(main);
 
-module.exports = { evaluateLint, LINT_REASON, OPT_OUT_LABEL, isUserFacing, isFragment };
+module.exports = { evaluateLint, LINT_REASON, OPT_OUT_LABEL, isUserFacing, isFragment, DEFAULT_BASE };
diff --git a/scripts/lint-docs-required.cjs b/scripts/lint-docs-required.cjs
index a6580cb4a..3bcce28ca 100755
--- a/scripts/lint-docs-required.cjs
+++ b/scripts/lint-docs-required.cjs
@@ -16,6 +16,10 @@
 const { parseFragment, FRAGMENT_ERROR } = require('./changeset/parse.cjs');
 const { ExitError, runMain } = require('./lib/cli-exit.cjs');
 
+// #2988: the repo's integration/default branch — the base every PR targets.
+// Used as the local fallback when GITHUB_BASE_REF is unset (CI sets it).
+const DEFAULT_BASE = 'next';
+
 const LINT_REASON = Object.freeze({
   OK_NO_TRIGGERING_FRAGMENTS: 'ok_no_triggering_fragments',
   OK_DOCS_UPDATED: 'ok_docs_updated',
@@ -149,7 +153,10 @@ function main() {
     } catch { /* fall through */ }
   }
 
-  const base = process.env.GITHUB_BASE_REF || 'main';
+  // #2988: local fallback must match the repo's integration branch (`next`),
+  // not the release branch (`main`). CI sets GITHUB_BASE_REF explicitly; the
+  // fallback only fires locally, where `next` is the base every PR targets.
+  const base = process.env.GITHUB_BASE_REF || DEFAULT_BASE;
   let changedFiles = [];
   try {
     // execFileSync with argv — no shell, so a malicious GITHUB_BASE_REF
@@ -216,6 +223,7 @@ module.exports = {
   OPT_OUT_LABEL,
   TRIGGERING_TYPES,
   FRAGMENT_ERROR,
+  DEFAULT_BASE,
   isFragmentPath,
   isDocsFile,
   isExemptFragment,
diff --git a/src/roadmap-command-router.cts b/src/roadmap-command-router.cts
index 7ef26d5a1..7b54d8cf4 100644
--- a/src/roadmap-command-router.cts
+++ b/src/roadmap-command-router.cts
@@ -21,6 +21,9 @@ const { planningDir } = planningWorkspace;
 // eslint-disable-next-line @typescript-eslint/no-require-imports
 import configLoaderMod = require('./config-loader.cjs');
 const { loadConfig } = configLoaderMod;
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+import cliExitMod = require('./cli-exit.cjs');
+const { ExitError } = cliExitMod;
 
 // ─── Types ────────────────────────────────────────────────────────────────────
 
@@ -143,11 +146,43 @@ function routeRoadmapCommand({ roadmap, args, cwd, raw, error }: RouteRoadmapCom
       'annotate-dependencies': () => roadmap.cmdRoadmapAnnotateDependencies(cwd, args[2], raw),
       'validate': () => {
         const roadmapPath = path.join(planningDir(cwd), 'ROADMAP.md');
-        let roadmapContent = '';
+        const warnings: Array<{ code: string; message: string }> = [];
+
+        // #2978: structural validation. A verb named "validate" that cannot
+        // produce a negative result provides false assurance. Before the
+        // opt-in milestone-prefix check, verify the file is structurally a
+        // roadmap at all.
+        let roadmapContent: string;
         try {
           roadmapContent = fs.readFileSync(roadmapPath, 'utf8');
         } catch {
-          // ROADMAP.md missing — return empty warnings
+          // ROADMAP.md missing — not silent success.
+          warnings.push({ code: 'V001', message: 'ROADMAP.md not found or unreadable' });
+          const result = { warnings };
+          process.stdout.write(raw ? JSON.stringify(result) : JSON.stringify(result, null, 2));
+          throw new ExitError(1);
+        }
+
+        // Empty or whitespace-only.
+        if (roadmapContent.trim() === '') {
+          warnings.push({ code: 'V002', message: 'ROADMAP.md is empty' });
+        }
+
+        // Malformed frontmatter — a `---` opener with no matching closer.
+        // Tolerate a leading BOM (#3057) before the fence.
+        const contentAfterBom = roadmapContent.replace(/^\uFEFF/, '');
+        if (contentAfterBom.startsWith('---')) {
+          const closeMatch = contentAfterBom.slice(3).match(/\r?\n---\s*(\r?\n|$)/);
+          if (!closeMatch) {
+            warnings.push({ code: 'V003', message: 'ROADMAP.md frontmatter is malformed (unterminated --- fence)' });
+          }
+        }
+
+        // No recognizable phase structure — at least one `### Phase N:` heading.
+        // Mirrors the phase-heading pattern used across roadmap-parser.cts.
+        const hasPhaseEntry = /^#{2,4}\s*Phase\s+\S/im.test(roadmapContent);
+        if (!hasPhaseEntry && !warnings.some((w) => w.code === 'V002')) {
+          warnings.push({ code: 'V004', message: 'ROADMAP.md contains no recognizable phase entries (no "### Phase N:" headings)' });
         }
 
         // W021 only fires when phase_id_convention is explicitly 'milestone-prefixed'.
@@ -173,13 +208,17 @@ function routeRoadmapCommand({ roadmap, args, cwd, raw, error }: RouteRoadmapCom
             }
           }
         }
-        const warnings = (convention === 'milestone-prefixed')
-          ? checkW021(roadmapContent)
-          : [];
+        if (convention === 'milestone-prefixed') {
+          warnings.push(...checkW021(roadmapContent));
+        }
 
         const result = { warnings };
-        if (raw) process.stdout.write(JSON.stringify(result));
-        else process.stdout.write(JSON.stringify(result, null, 2));
+        process.stdout.write(raw ? JSON.stringify(result) : JSON.stringify(result, null, 2));
+        // #2978: exit non-zero on any warning, per the documented contract
+        // ("exits non-zero on any error or warning").
+        if (warnings.length > 0) {
+          throw new ExitError(1);
+        }
       },
       'upgrade': () => {
         const dryRun = !args.includes('--apply');
diff --git a/src/state-transition.cts b/src/state-transition.cts
index 9db1f96f3..362180719 100644
--- a/src/state-transition.cts
+++ b/src/state-transition.cts
@@ -195,8 +195,25 @@ export function applyStatePreservation(input: StatePreservationInput): StatePres
       const derived = (postFm['progress'] ?? {}) as Record<string, unknown>;
       const merged: Record<string, unknown> = { ...derived };
       if (curated) {
+        // #2440: total_plans and total_phases always take the derived value.
+        // #2969: completed_plans and completed_phases take the derived value
+        // when it is GREATER than the curated value (gap-closure plans that
+        // completed after the plan count grew) — ratcheting UP only, never
+        // deriving downward (preserves the #3242 curated-progress protection
+        // for cases unrelated to plan-count growth, e.g. a deleted SUMMARY).
+        // percent also takes the derived value — the resync recomputed it from
+        // disk counts, and a stale curated percent would be incoherent against
+        // the ratcheted-up completed counts (e.g. 54/54 at 93%).
+        const ratchetUpKeys = new Set(['completed_plans', 'completed_phases']);
         for (const [key, value] of Object.entries(curated)) {
-          if (key !== 'total_plans' && key !== 'total_phases') {
+          if (key === 'total_plans' || key === 'total_phases' || key === 'percent') continue;
+          if (ratchetUpKeys.has(key)) {
+            const derivedNum = typeof derived[key] === 'number' ? derived[key] : -Infinity;
+            const curatedNum = typeof value === 'number' ? value : -Infinity;
+            // Take the derived value only when it ratchets up; else keep curated.
+            if (derivedNum > curatedNum) continue;
+            merged[key] = value;
+          } else {
             merged[key] = value;
           }
         }
diff --git a/tests/changeset-lint.test.cjs b/tests/changeset-lint.test.cjs
index dff7ab16a..6775d142d 100644
--- a/tests/changeset-lint.test.cjs
+++ b/tests/changeset-lint.test.cjs
@@ -8,7 +8,8 @@ const fs = require('node:fs');
 const os = require('node:os');
 const cp = require('node:child_process');
 
-const { evaluateLint, LINT_REASON } = require(path.join(__dirname, '..', 'scripts', 'changeset', 'lint.cjs'));
+const { evaluateLint, LINT_REASON, DEFAULT_BASE: CHANGESET_DEFAULT_BASE } = require(path.join(__dirname, '..', 'scripts', 'changeset', 'lint.cjs'));
+const { DEFAULT_BASE: DOCS_DEFAULT_BASE } = require(path.join(__dirname, '..', 'scripts', 'lint-docs-required.cjs'));
 
 const ROOT = path.join(__dirname, '..');
 const LINT_SCRIPT = path.join(ROOT, 'scripts', 'changeset', 'lint.cjs');
@@ -297,3 +298,19 @@ describe('changeset lint: main() end-to-end wiring (#1006)', () => {
     assert.ok(!deletedEntry, `deleted fragment must not appear in failures, got: ${JSON.stringify(failures)}`);
   });
 });
+
+// ─── #2988: local base fallback parity ──────────────────────────────────────
+
+describe('#2988: changeset + docs lints resolve the same local base fallback', () => {
+  test('both lints default to `next` (the integration branch), not `main`', () => {
+    assert.strictEqual(CHANGESET_DEFAULT_BASE, 'next',
+      `changeset lint DEFAULT_BASE must be 'next', got '${CHANGESET_DEFAULT_BASE}'`);
+    assert.strictEqual(DOCS_DEFAULT_BASE, 'next',
+      `docs lint DEFAULT_BASE must be 'next', got '${DOCS_DEFAULT_BASE}'`);
+  });
+
+  test('both lints resolve the same base given the same environment (parity)', () => {
+    assert.strictEqual(CHANGESET_DEFAULT_BASE, DOCS_DEFAULT_BASE,
+      `the two lints must not diverge on base resolution: changeset='${CHANGESET_DEFAULT_BASE}' docs='${DOCS_DEFAULT_BASE}'`);
+  });
+});
diff --git a/tests/cli-exit.test.cjs b/tests/cli-exit.test.cjs
index 03a1de939..21823bd14 100644
--- a/tests/cli-exit.test.cjs
+++ b/tests/cli-exit.test.cjs
@@ -183,11 +183,18 @@ describe('runMain', () => {
 describe('regressions', () => {
   /** Spawn a one-shot script that sets json-error mode and calls runMain with a throwing handler. */
   function spawnJsonErrorRun({ jsonMode, errorType = 'TypeError', message = 'unexpected boom' } = {}) {
+    // ExitError lives in the same module as runMain; import it when the test
+    // wants to exercise the ExitError carve-out path. ExitError takes (code, message).
+    const isExitError = errorType === 'ExitError';
+    const destructure = isExitError ? '{ runMain, ExitError }' : '{ runMain }';
+    const throwExpr = isExitError
+      ? `new ExitError(1, ${JSON.stringify(message)})`
+      : `new ${errorType}(${JSON.stringify(message)})`;
     const script = `
       const io = require(${JSON.stringify(IO_PATH)});
-      const { runMain } = require(${JSON.stringify(BUILT_CLI_EXIT_PATH)});
+      const ${destructure} = require(${JSON.stringify(BUILT_CLI_EXIT_PATH)});
       io.setJsonErrorMode(${jsonMode ? 'true' : 'false'});
-      runMain(() => { throw new ${errorType}(${JSON.stringify(message)}); });
+      runMain(() => { throw ${throwExpr}; });
       setImmediate(() => {});
     `;
     return spawnSync(process.execPath, ['-e', script], { encoding: 'utf-8' });
@@ -245,5 +252,35 @@ describe('regressions', () => {
         `expected "unexpected boom" in stderr, got: ${stderrTrimmed.slice(0, 200)}`
       );
     });
+
+    // #2979: characterization test pinning the two error paths under json-errors
+    // mode. The structured envelope covers non-ExitError failures; ExitError
+    // (usage errors) intentionally emits plain text with its own exit code.
+    // Both halves asserted together so the code cannot drift toward the doc's
+    // prior overstated claim that EVERY error emits JSON.
+    test('#2979: ExitError emits plain text (not JSON) even under --json-errors; non-ExitError emits the envelope', () => {
+      // ExitError path: plain text, own exit code, NOT a JSON object.
+      const exitResult = spawnJsonErrorRun({
+        jsonMode: true,
+        errorType: 'ExitError',
+        message: 'Usage: gsd-tools <command> [args]',
+      });
+      assert.strictEqual(exitResult.status, 1, 'ExitError exits with its code');
+      const exitStderr = exitResult.stderr.trim();
+      let exitParsed = null;
+      try { exitParsed = JSON.parse(exitStderr); } catch { /* expected — plain text */ }
+      assert.strictEqual(exitParsed, null,
+        `ExitError must emit plain text, not JSON; got: ${exitStderr.slice(0, 200)}`);
+      assert.ok(exitStderr.includes('Usage'),
+        `ExitError plain-text message must reach stderr; got: ${exitStderr.slice(0, 200)}`);
+
+      // Non-ExitError path: structured JSON envelope.
+      const envResult = spawnJsonErrorRun({ jsonMode: true });
+      assert.strictEqual(envResult.status, 1);
+      const envParsed = JSON.parse(envResult.stderr.trim());
+      assert.strictEqual(envParsed.ok, false);
+      assert.strictEqual(envParsed.reason, 'sdk_fail_fast');
+      assert.ok(envParsed.message, 'envelope must carry a message');
+    });
   });
 });
diff --git a/tests/emitted-drift-acks/2989-code-review-anchored-diff-base.json b/tests/emitted-drift-acks/2989-code-review-anchored-diff-base.json
new file mode 100644
index 000000000..3452f97c2
--- /dev/null
+++ b/tests/emitted-drift-acks/2989-code-review-anchored-diff-base.json
@@ -0,0 +1,6 @@
+{
+  "version": 1,
+  "paths": {
+    "code-review.md": "#2989: the diff-base fallback's git log --grep was changed from an unanchored bare phase number (matching version strings, dates, issue refs) to an anchored '[Pp]hase N\\b' with --extended-regexp, plus a 5-line comment explaining the anchor. Makes the fail-closed branch reachable when no commit genuinely references the phase."
+  }
+}
diff --git a/tests/milestone-prefixed-convention.test.cjs b/tests/milestone-prefixed-convention.test.cjs
index f54e42a1a..455b42632 100644
--- a/tests/milestone-prefixed-convention.test.cjs
+++ b/tests/milestone-prefixed-convention.test.cjs
@@ -89,7 +89,8 @@ describe('W021 — milestone-prefixed phase ID convention', () => {
     ]);
 
     const result = runGsdTools(['roadmap', 'validate'], tmpDir);
-    assert.ok(result.success, `roadmap validate should exit 0 even with warnings: ${result.error}`);
+    // #2978: validate now exits non-zero on any warning (per its documented contract).
+    assert.strictEqual(result.success, false, `roadmap validate must exit non-zero on W021 warnings: ${result.error}`);
 
     const out = JSON.parse(result.output);
     assert.ok(Array.isArray(out.warnings), 'output.warnings should be an array');
@@ -219,7 +220,8 @@ describe('W021 — milestone-prefixed phase ID convention', () => {
     ]);
 
     const result = runGsdTools(['roadmap', 'validate'], tmpDir);
-    assert.ok(result.success, `roadmap validate failed: ${result.error}`);
+    // #2978: validate now exits non-zero on any warning (per its documented contract).
+    assert.strictEqual(result.success, false, `roadmap validate must exit non-zero on W021 warnings: ${result.error}`);
 
     const out = JSON.parse(result.output);
     const w021 = (out.warnings || []).filter(w => w.code === 'W021');
diff --git a/tests/pi-extension-reachability.test.cjs b/tests/pi-extension-reachability.test.cjs
index 8d51730cb..c2208f6b5 100644
--- a/tests/pi-extension-reachability.test.cjs
+++ b/tests/pi-extension-reachability.test.cjs
@@ -63,23 +63,28 @@ test('REACHABILITY: the /gsd handler dispatches a real family through gsd-tools.
   const dir = createTempDir();
   try {
     const result = await pi._recorded.commands['gsd'].handler('progress json', { cwd: dir });
-    assert.equal(typeof result, 'string', '/gsd handler returns a string result');
-    const parsed = JSON.parse(result);
+    // #2991: handler returns { content: [{ type: 'text', text }] } (Pi's display shape), not a bare string.
+    assert.ok(result && Array.isArray(result.content) && result.content[0].type === 'text',
+      `/gsd handler must return Pi's display shape { content: [{ type: 'text', text }] }; got: ${JSON.stringify(result).slice(0, 200)}`);
+    const parsed = JSON.parse(result.content[0].text);
     assert.equal(typeof parsed.percent, 'number', '/gsd dispatch reached gsd-tools.cjs for real (the engine was reached)');
   } finally {
     cleanup(dir);
   }
 });
 
-test('REACHABILITY: an unknown family surfaces a clear GSD error string, not a throw', async () => {
+test('REACHABILITY: an unknown family surfaces a clear GSD error, not a throw', async () => {
   const pi = mockPi();
   gsdPiExtension(pi);
   const dir = createTempDir();
   try {
     const result = await pi._recorded.commands['gsd'].handler('no-such-family-8675309', { cwd: dir });
-    assert.equal(typeof result, 'string');
-    assert.match(result, /GSD error:/);
-    assert.match(result, /no-such-family-8675309|Unknown command/);
+    // #2991: handler returns { content: [{ type: 'text', text }] } (Pi's display shape).
+    assert.ok(result && Array.isArray(result.content) && result.content[0].type === 'text',
+      `error result must carry Pi's display shape; got: ${JSON.stringify(result).slice(0, 200)}`);
+    const text = result.content[0].text;
+    assert.match(text, /GSD error:/);
+    assert.match(text, /no-such-family-8675309|Unknown command/);
   } finally {
     cleanup(dir);
   }
diff --git a/tests/roadmap.test.cjs b/tests/roadmap.test.cjs
index 8b9e60d6f..9b518f39b 100644
--- a/tests/roadmap.test.cjs
+++ b/tests/roadmap.test.cjs
@@ -3612,3 +3612,79 @@ describe('bug #1103 — annotate-dependencies preserves newline before Plans: he
 });
   });
 }
+
+// ─────────────────────────────────────────────────────────────────────────────
+// bug #2978: roadmap validate returns {"warnings":[]} for every input
+// ─────────────────────────────────────────────────────────────────────────────
+
+describe('bug #2978: roadmap validate performs structural validation', () => {
+  test('empty (zero-byte) ROADMAP.md → non-empty warnings, non-zero exit', () => {
+    const tmpDir = createTempProject('gsd-2978-empty-');
+    try {
+      fs.writeFileSync(path.join(tmpDir, '.planning', 'ROADMAP.md'), '');
+      const result = runGsdTools(['roadmap', 'validate', '--raw'], tmpDir);
+      assert.strictEqual(result.success, false, 'empty file must exit non-zero');
+      const payload = JSON.parse(result.output);
+      assert.ok(Array.isArray(payload.warnings) && payload.warnings.length > 0,
+        `empty file must produce non-empty warnings; got: ${JSON.stringify(payload)}`);
+    } finally { cleanup(tmpDir); }
+  });
+
+  test('garbage/non-roadmap text → non-empty warnings, non-zero exit', () => {
+    const tmpDir = createTempProject('gsd-2978-garbage-');
+    try {
+      fs.writeFileSync(path.join(tmpDir, '.planning', 'ROADMAP.md'), 'not a roadmap at all');
+      const result = runGsdTools(['roadmap', 'validate', '--raw'], tmpDir);
+      assert.strictEqual(result.success, false, 'garbage must exit non-zero');
+      const payload = JSON.parse(result.output);
+      assert.ok(payload.warnings.length > 0, 'garbage must produce warnings');
+    } finally { cleanup(tmpDir); }
+  });
+
+  test('missing ROADMAP.md → non-empty warnings, non-zero exit', () => {
+    const tmpDir = createTempProject('gsd-2978-missing-');
+    try {
+      // createTempProject creates .planning/phases but no ROADMAP.md — don't write one
+      const result = runGsdTools(['roadmap', 'validate', '--raw'], tmpDir);
+      assert.strictEqual(result.success, false, 'missing file must exit non-zero');
+      const payload = JSON.parse(result.output);
+      assert.ok(payload.warnings.length > 0, 'missing file must produce warnings');
+    } finally { cleanup(tmpDir); }
+  });
+
+  test('truncated frontmatter (unterminated ---) → non-empty warnings', () => {
+    const tmpDir = createTempProject('gsd-2978-trunc-');
+    try {
+      fs.writeFileSync(path.join(tmpDir, '.planning', 'ROADMAP.md'),
+        '---\nmilestone: v1.0\n### Phase 1: Setup\n');
+      const result = runGsdTools(['roadmap', 'validate', '--raw'], tmpDir);
+      assert.strictEqual(result.success, false, 'truncated frontmatter must exit non-zero');
+      const payload = JSON.parse(result.output);
+      assert.ok(payload.warnings.length > 0, 'truncated frontmatter must produce warnings');
+    } finally { cleanup(tmpDir); }
+  });
+
+  test('well-formed roadmap → warnings: [], exit 0 (no false positive)', () => {
+    const tmpDir = createTempProject('gsd-2978-good-');
+    try {
+      fs.writeFileSync(path.join(tmpDir, '.planning', 'ROADMAP.md'),
+        '# Roadmap\n\n## v1.0\n\n### Phase 1: Foundation\n**Goal:** setup\n');
+      const result = runGsdTools(['roadmap', 'validate', '--raw'], tmpDir);
+      assert.ok(result.success, `well-formed roadmap must exit 0; got: ${result.error}`);
+      const payload = JSON.parse(result.output);
+      assert.deepStrictEqual(payload.warnings, [], 'well-formed roadmap must have no warnings');
+    } finally { cleanup(tmpDir); }
+  });
+
+  test('BOM-prefixed well-formed roadmap → warnings: [], exit 0 (not corruption)', () => {
+    const tmpDir = createTempProject('gsd-2978-bom-');
+    try {
+      fs.writeFileSync(path.join(tmpDir, '.planning', 'ROADMAP.md'),
+        '\uFEFF# Roadmap\n\n### Phase 1: Foundation\n**Goal:** setup\n');
+      const result = runGsdTools(['roadmap', 'validate', '--raw'], tmpDir);
+      assert.ok(result.success, `BOM-prefixed roadmap must exit 0; got: ${result.error}`);
+      const payload = JSON.parse(result.output);
+      assert.deepStrictEqual(payload.warnings, [], 'BOM is not corruption');
+    } finally { cleanup(tmpDir); }
+  });
+});
diff --git a/tests/state-transition.test.cjs b/tests/state-transition.test.cjs
index 6b7409a2d..89b95e3b4 100644
--- a/tests/state-transition.test.cjs
+++ b/tests/state-transition.test.cjs
@@ -1340,6 +1340,61 @@ describe('ADR-1769 #1796: applyStatePreservation — table-driven post-sync cons
       'total_plans equality → derived value (identity)');
   });
 
+  test('#2969: deriveProgressKeys=true — completed_plans ratchets UP when disk count exceeds curated (gap-closure plans completed)', () => {
+    // Gap-closure scenario: a phase had 50 plans all summarized (completed_plans: 50),
+    // then 4 gap-closure plans were added (total_plans -> 54) and all 4 got SUMMARYs.
+    // Disk scan now counts 54 summaries. The curated completed_plans (50) must
+    // ratchet UP to the derived value (54), not stay pinned at 50 — otherwise
+    // completed_plans < total_plans forever even though every plan is summarized.
+    const curated = { progress: { total_plans: 54, completed_plans: 50, total_phases: 2, completed_phases: 1, percent: 93 } };
+    const r = applyStatePreservation({
+      preFm: curated,
+      preFmSnapshot: curated,
+      postFm: { progress: { total_plans: 54, completed_plans: 54, total_phases: 2, completed_phases: 1, percent: 100 } },
+      resync: false,
+      deriveProgressKeys: true,
+      ...untouched,
+    });
+    assert.equal(r.postFm.progress.total_plans, 54, 'total_plans takes derived value');
+    assert.equal(r.postFm.progress.completed_plans, 54,
+      'completed_plans must ratchet UP to derived (54 > curated 50 — gap-closure plans completed) (#2969)');
+    assert.equal(r.postFm.progress.percent, 100,
+      'percent must reflect the true completion fraction (54/54) (#2969)');
+  });
+
+  test('#2969 ratchet-down protection: deriveProgressKeys=true keeps curated when disk count < curated', () => {
+    // The ratchet must only go UP. If the disk count is somehow LOWER than
+    // curated (e.g. a SUMMARY was deleted), keep the curated value — do not
+    // derive downward. (#3242 curated-progress protection, scoped to deriveProgressKeys.)
+    const curated = { progress: { total_plans: 54, completed_plans: 50, percent: 93 } };
+    const r = applyStatePreservation({
+      preFm: curated,
+      preFmSnapshot: curated,
+      postFm: { progress: { total_plans: 54, completed_plans: 47, percent: 87 } },
+      resync: false,
+      deriveProgressKeys: true,
+      ...untouched,
+    });
+    assert.equal(r.postFm.progress.completed_plans, 50,
+      'completed_plans must NOT derive downward (47 < curated 50) — ratchet-up only (#2969/#3242)');
+  });
+
+  test('#2969 body-only write protection: deriveProgressKeys absent keeps wholesale restore', () => {
+    // state.update/patch (no deriveProgressKeys flag) must keep the full #3242
+    // wholesale curated restore — completed_plans never moves for a body-only edit.
+    const curated = { progress: { total_plans: 54, completed_plans: 50, percent: 93 } };
+    const r = applyStatePreservation({
+      preFm: curated,
+      preFmSnapshot: curated,
+      postFm: { progress: { total_plans: 54, completed_plans: 54, percent: 100 } },
+      resync: false,
+      // deriveProgressKeys NOT set — body-only write path
+      ...untouched,
+    });
+    assert.equal(r.postFm.progress.completed_plans, 50,
+      'body-only write must keep curated completed_plans (no deriveProgressKeys) (#2969/#3242)');
+  });
+
   test('progress: NOT restored when transition re-derives from disk (resync=true) — sync/advancePlan/completePhase path', () => {
     const recomputed = { progress: { total_phases: 5, completed_phases: 1, percent: 20 } };
     const r = applyStatePreservation({