From b4d386c779b89f64777d76b42bc4c7e88c89f706 Mon Sep 17 00:00:00 2001
From: Vincent Koc <vincentkoc@ieee.org>
Date: Fri, 31 Jul 2026 20:17:58 +0200
Subject: [PATCH 1/3] fix(review): materialize exact PR source

---
 .github/workflows/sweep.yml | 62 +++++++++++++++++++++++++++-----
 test/sweep-workflow.test.ts | 72 +++++++++++++++++++++++++++++++++++++
 2 files changed, 126 insertions(+), 8 deletions(-)

diff --git a/.github/workflows/sweep.yml b/.github/workflows/sweep.yml
index 4b2ebf404f..334166ce52 100644
--- a/.github/workflows/sweep.yml
+++ b/.github/workflows/sweep.yml
@@ -857,7 +857,12 @@ jobs:
             ${{ steps.target.outputs.target_repo_name }}-git-${{ runner.os }}-
 
       - name: Check out target repository
+        id: checkout-target
         if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' }}
+        env:
+          ITEM_KIND: ${{ steps.live-item.outputs.item_kind }}
+          ITEM_NUMBER: ${{ steps.target.outputs.item_number }}
+          SOURCE_HEAD_SHA: ${{ fromJSON(steps.claim-exact-review-queue.outputs.decision).sourceHeadSha || '' }}
         run: |
           set -euo pipefail
           url="https://github.com/${{ steps.target.outputs.target_repo }}.git"
@@ -887,10 +892,39 @@ jobs:
             git clone --bare --filter=blob:none --single-branch --branch "$target_branch" "$url" "$cache_dir"
             git clone --filter=blob:none --branch "$target_branch" --single-branch "$url" "$checkout_dir"
           fi
+          if [ "$ITEM_KIND" = "pull_request" ]; then
+            if ! [[ "$SOURCE_HEAD_SHA" =~ ^[0-9a-f]{40}$ ]]; then
+              echo "::error::Exact PR review requires a valid leased source head SHA."
+              exit 1
+            fi
+            git -C "$checkout_dir" fetch --force --depth=50 origin "refs/pull/${ITEM_NUMBER}/head"
+            fetched_head="$(git -C "$checkout_dir" rev-parse FETCH_HEAD)"
+            if [ "$fetched_head" != "$SOURCE_HEAD_SHA" ]; then
+              echo "::notice::Fetched PR head $fetched_head moved past leased source head $SOURCE_HEAD_SHA; skipping review and requeueing the latest source."
+              echo "source_drift=true" >> "$GITHUB_OUTPUT"
+              exit 0
+            else
+              git -C "$checkout_dir" checkout --detach "$SOURCE_HEAD_SHA"
+              checked_out_head="$(git -C "$checkout_dir" rev-parse HEAD)"
+              if [ "$checked_out_head" != "$SOURCE_HEAD_SHA" ]; then
+                echo "::error::Target checkout head $checked_out_head does not match leased source head $SOURCE_HEAD_SHA."
+                exit 1
+              fi
+            fi
+          fi
+          echo "source_drift=false" >> "$GITHUB_OUTPUT"
           git -C "$checkout_dir" rev-parse --short HEAD
 
+      - name: Requeue exact review after source drift
+        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.checkout-target.outputs.source_drift == 'true' }}
+        run: echo "::notice::The leased PR source moved before review; this run is a successful no-op and the durable queue will review the latest head."
+
+      - name: Materialize Codex source for OpenClaw review
+        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.checkout-target.outputs.source_drift != 'true' && steps.target.outputs.target_repo == 'openclaw/openclaw' }}
+        run: git clone --filter=blob:none --depth=1 https://github.com/openai/codex.git codex
+
       - name: Mark re-review command in progress
-        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' }}
+        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.checkout-target.outputs.source_drift != 'true' }}
         continue-on-error: true
         env:
           GH_TOKEN: ${{ steps.target-write-token.outputs.token }}
@@ -911,7 +945,7 @@ jobs:
             --wait-ms 120000
 
       - uses: ./.github/actions/setup-codex
-        if: ${{ env.CLAWSWEEPER_RUNNER != 'openclaw' && steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' }}
+        if: ${{ env.CLAWSWEEPER_RUNNER != 'openclaw' && steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.checkout-target.outputs.source_drift != 'true' }}
         env:
           OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
           CLAWSWEEPER_INTERNAL_MODEL: ${{ secrets.CLAWSWEEPER_MODEL }}
@@ -919,11 +953,11 @@ jobs:
           login-status: "true"
 
       - uses: ./.github/actions/setup-openclaw
-        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' }}
+        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.checkout-target.outputs.source_drift != 'true' }}
 
       - name: Reserve exact review lease
         id: reserve-exact-review-lease
-        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' }}
+        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.checkout-target.outputs.source_drift != 'true' }}
         env:
           GH_TOKEN: ${{ steps.target-write-token.outputs.token }}
           TARGET_REPO: ${{ steps.target.outputs.target_repo }}
@@ -1232,7 +1266,7 @@ jobs:
           fi
 
       - name: Finalize exact event action ledger
-        if: ${{ always() && steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' }}
+        if: ${{ always() && steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.checkout-target.outputs.source_drift != 'true' }}
         continue-on-error: true
         env:
           REVIEW_EXIT_CODE: ${{ steps.review-exact-event-item.outputs.exit_code || '' }}
@@ -1251,7 +1285,7 @@ jobs:
 
       - name: Create exact review artifact bundle
         id: create-exact-review-bundle
-        if: ${{ always() && steps.claim-exact-review-queue.outputs.claimed == 'true' && !cancelled() && steps.target.outputs.target_enabled == 'true' && steps.live-item.outcome == 'success' && steps.live-item.outputs.admission_retry != 'true' && steps.setup-pnpm.outcome == 'success' && steps.review-exact-event-item.outputs.superseded != 'true' && (steps.live-item.outputs.proceed != 'true' || (steps.review-exact-event-item.outcome == 'success' && steps.review-exact-event-item.outputs.retry_at == '')) }}
+        if: ${{ always() && steps.claim-exact-review-queue.outputs.claimed == 'true' && !cancelled() && steps.target.outputs.target_enabled == 'true' && steps.live-item.outcome == 'success' && steps.live-item.outputs.admission_retry != 'true' && steps.setup-pnpm.outcome == 'success' && steps.checkout-target.outputs.source_drift != 'true' && steps.review-exact-event-item.outputs.superseded != 'true' && (steps.live-item.outputs.proceed != 'true' || (steps.review-exact-event-item.outcome == 'success' && steps.review-exact-event-item.outputs.retry_at == '')) }}
         env:
           EXACT_REVIEW_ACTION_LEDGER_ROOT: ${{ env.CLAWSWEEPER_ACTION_LEDGER_OUTPUT_ROOT }}
           EXACT_REVIEW_BUNDLE_DIR: .artifacts/exact-review-bundle
@@ -1471,13 +1505,17 @@ jobs:
           RUN_URL: https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}
           REVIEW_OUTCOME: ${{ steps.review-exact-event-item.outcome }}
           REVIEW_SUPERSEDED: ${{ steps.review-exact-event-item.outputs.superseded || 'false' }}
+          SOURCE_DRIFT: ${{ steps.checkout-target.outputs.source_drift || 'false' }}
           RESERVATION_STATUS: ${{ steps.reserve-exact-review-lease.outputs.status }}
           RETRY_AT: ${{ steps.reserve-exact-review-lease.outputs.retry_at || steps.review-exact-event-item.outputs.retry_at }}
           CLAWSWEEPER_ACTION_LEDGER_DISABLED: "1"
         run: |
           state="Failed"
           detail="The exact review did not produce a publishable artifact. The durable queue will retry it."
-          if [ "$RESERVATION_STATUS" = "superseded" ] || [ "$REVIEW_SUPERSEDED" = "true" ]; then
+          if [ "$SOURCE_DRIFT" = "true" ]; then
+            state="Waiting"
+            detail="The pull request head moved before review. The durable queue will review the latest source."
+          elif [ "$RESERVATION_STATUS" = "superseded" ] || [ "$REVIEW_SUPERSEDED" = "true" ]; then
             state="Waiting"
             detail="A newer exact-review queue owner superseded this run. This run completed as a no-op."
           elif [ "$RESERVATION_STATUS" = "held" ]; then
@@ -1505,13 +1543,17 @@ jobs:
           LIVE_OUTCOME: ${{ steps.live-item.outcome }}
           REVIEW_OUTCOME: ${{ steps.review-exact-event-item.outcome }}
           REVIEW_SUPERSEDED: ${{ steps.review-exact-event-item.outputs.superseded || 'false' }}
+          SOURCE_DRIFT: ${{ steps.checkout-target.outputs.source_drift || 'false' }}
           RESERVATION_STATUS: ${{ steps.reserve-exact-review-lease.outputs.status }}
           PUBLICATION_QUEUE_OUTCOME: ${{ steps.queue-exact-review-publication.outcome }}
           DIRECT_PUBLICATION_ACCEPTED: ${{ steps.direct-exact-review-publication.outputs.accepted }}
         run: |
           outcome=failure
           requeue_latest=false
-          if [ "$ADMISSION_RETRY" = "true" ]; then
+          if [ "$SOURCE_DRIFT" = "true" ]; then
+            outcome=success
+            requeue_latest=true
+          elif [ "$ADMISSION_RETRY" = "true" ]; then
             outcome=success
             requeue_latest=true
           elif [ "$TARGET_ENABLED" = "false" ]; then
@@ -3290,6 +3332,10 @@ jobs:
           fi
           git -C "$checkout_dir" rev-parse --short HEAD
 
+      - name: Materialize Codex source for OpenClaw review
+        if: ${{ needs.plan.outputs.target_repo == 'openclaw/openclaw' }}
+        run: git clone --filter=blob:none --depth=1 https://github.com/openai/codex.git codex
+
       - name: Mark shard start
         id: shard-start
         run: echo "started_at=$(date -u '+%Y-%m-%dT%H:%M:%SZ')" >> "$GITHUB_OUTPUT"
diff --git a/test/sweep-workflow.test.ts b/test/sweep-workflow.test.ts
index 208b1a20e8..0d7658ae93 100644
--- a/test/sweep-workflow.test.ts
+++ b/test/sweep-workflow.test.ts
@@ -3610,6 +3610,78 @@ test("sweep target checkouts retry without cached references", () => {
   }
 });
 
+test("exact PR reviews fail closed unless the leased source head is checked out", () => {
+  const workflow = YAML.parse(readText(".github/workflows/sweep.yml")) as {
+    jobs: Record<
+      string,
+      {
+        steps: Array<{
+          name?: string;
+          if?: string;
+          env?: Record<string, string>;
+          run?: string;
+        }>;
+      }
+    >;
+  };
+  const steps = workflow.jobs["event-review-apply"]!.steps;
+  const checkoutIndex = steps.findIndex((step) => step.name === "Check out target repository");
+  const codexIndex = steps.findIndex(
+    (step) => step.name === "Materialize Codex source for OpenClaw review",
+  );
+  const reviewIndex = steps.findIndex((step) => step.name === "Review exact event item");
+  const checkout = steps[checkoutIndex]!;
+  const codex = steps[codexIndex]!;
+  const requeue = steps.find((step) => step.name === "Requeue exact review after source drift")!;
+  const generation = steps.find((step) => step.name === "Export exact review generation result")!;
+
+  assert.ok(checkoutIndex >= 0);
+  assert.ok(codexIndex > checkoutIndex);
+  assert.ok(reviewIndex > codexIndex);
+  assert.equal(
+    checkout.env?.SOURCE_HEAD_SHA,
+    "${{ fromJSON(steps.claim-exact-review-queue.outputs.decision).sourceHeadSha || '' }}",
+  );
+  assert.match(checkout.run ?? "", /refs\/pull\/\$\{ITEM_NUMBER\}\/head/);
+  assert.match(checkout.run ?? "", /fetched_head" != "\$SOURCE_HEAD_SHA/);
+  assert.match(checkout.run ?? "", /source_drift=true/);
+  assert.match(checkout.run ?? "", /exit 0/);
+  assert.match(checkout.run ?? "", /checkout --detach "\$SOURCE_HEAD_SHA"/);
+  assert.match(checkout.run ?? "", /checked_out_head" != "\$SOURCE_HEAD_SHA/);
+  assert.equal(
+    requeue.if,
+    "${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.checkout-target.outputs.source_drift == 'true' }}",
+  );
+  assert.match(codex.if ?? "", /source_drift != 'true'/);
+  assert.match(codex.if ?? "", /target_repo == 'openclaw\/openclaw'/);
+  assert.match(codex.run ?? "", /https:\/\/github\.com\/openai\/codex\.git codex/);
+  assert.equal(
+    generation.env?.SOURCE_DRIFT,
+    "${{ steps.checkout-target.outputs.source_drift || 'false' }}",
+  );
+  assert.match(generation.run ?? "", /SOURCE_DRIFT" = "true"/);
+  assert.match(generation.run ?? "", /requeue_latest=true/);
+});
+
+test("scheduled OpenClaw review workers materialize sibling Codex source", () => {
+  const workflow = YAML.parse(readText(".github/workflows/sweep.yml")) as {
+    jobs: Record<string, { steps: Array<{ name?: string; if?: string; run?: string }> }>;
+  };
+  const steps = workflow.jobs.review!.steps;
+  const checkoutIndex = steps.findIndex((step) => step.name === "Check out target repository");
+  const codexIndex = steps.findIndex(
+    (step) => step.name === "Materialize Codex source for OpenClaw review",
+  );
+  const reviewIndex = steps.findIndex((step) => step.name === "Review shard");
+  const codex = steps[codexIndex]!;
+
+  assert.ok(checkoutIndex >= 0);
+  assert.ok(codexIndex > checkoutIndex);
+  assert.ok(reviewIndex > codexIndex);
+  assert.equal(codex.if, "${{ needs.plan.outputs.target_repo == 'openclaw/openclaw' }}");
+  assert.match(codex.run ?? "", /https:\/\/github\.com\/openai\/codex\.git codex/);
+});
+
 test("target sweep runs count as background review capacity", () => {
   const workflow = readText(".github/workflows/sweep.yml");
   const capacityBlock = workflow.slice(

From 9da9049ed697594aff34a1391972179b5500358d Mon Sep 17 00:00:00 2001
From: Vincent Koc <vincentkoc@ieee.org>
Date: Fri, 31 Jul 2026 22:37:01 +0200
Subject: [PATCH 2/3] refactor(review): test leased source materialization

---
 .github/workflows/sweep.yml             |  31 ++-----
 CHANGELOG.md                            |   1 +
 package.json                            |   1 +
 src/repair/exact-review-source-cli.ts   |  71 +++++++++++++++
 src/repair/exact-review-source.ts       |  61 +++++++++++++
 test/repair/exact-review-source.test.ts | 115 ++++++++++++++++++++++++
 test/sweep-workflow.test.ts             |  29 ++++--
 7 files changed, 276 insertions(+), 33 deletions(-)
 create mode 100644 src/repair/exact-review-source-cli.ts
 create mode 100644 src/repair/exact-review-source.ts
 create mode 100644 test/repair/exact-review-source.test.ts

diff --git a/.github/workflows/sweep.yml b/.github/workflows/sweep.yml
index 334166ce52..5af7f25a6b 100644
--- a/.github/workflows/sweep.yml
+++ b/.github/workflows/sweep.yml
@@ -892,28 +892,11 @@ jobs:
             git clone --bare --filter=blob:none --single-branch --branch "$target_branch" "$url" "$cache_dir"
             git clone --filter=blob:none --branch "$target_branch" --single-branch "$url" "$checkout_dir"
           fi
-          if [ "$ITEM_KIND" = "pull_request" ]; then
-            if ! [[ "$SOURCE_HEAD_SHA" =~ ^[0-9a-f]{40}$ ]]; then
-              echo "::error::Exact PR review requires a valid leased source head SHA."
-              exit 1
-            fi
-            git -C "$checkout_dir" fetch --force --depth=50 origin "refs/pull/${ITEM_NUMBER}/head"
-            fetched_head="$(git -C "$checkout_dir" rev-parse FETCH_HEAD)"
-            if [ "$fetched_head" != "$SOURCE_HEAD_SHA" ]; then
-              echo "::notice::Fetched PR head $fetched_head moved past leased source head $SOURCE_HEAD_SHA; skipping review and requeueing the latest source."
-              echo "source_drift=true" >> "$GITHUB_OUTPUT"
-              exit 0
-            else
-              git -C "$checkout_dir" checkout --detach "$SOURCE_HEAD_SHA"
-              checked_out_head="$(git -C "$checkout_dir" rev-parse HEAD)"
-              if [ "$checked_out_head" != "$SOURCE_HEAD_SHA" ]; then
-                echo "::error::Target checkout head $checked_out_head does not match leased source head $SOURCE_HEAD_SHA."
-                exit 1
-              fi
-            fi
-          fi
-          echo "source_drift=false" >> "$GITHUB_OUTPUT"
-          git -C "$checkout_dir" rev-parse --short HEAD
+          pnpm run --silent repair:exact-review-source -- \
+            --target-dir "$checkout_dir" \
+            --item-kind "$ITEM_KIND" \
+            --item-number "$ITEM_NUMBER" \
+            --source-head-sha "$SOURCE_HEAD_SHA"
 
       - name: Requeue exact review after source drift
         if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.checkout-target.outputs.source_drift == 'true' }}
@@ -1062,7 +1045,7 @@ jobs:
 
       - name: Review exact event item
         id: review-exact-event-item
-        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.reserve-exact-review-lease.outputs.status == 'posted' }}
+        if: ${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.checkout-target.outputs.source_drift != 'true' && steps.reserve-exact-review-lease.outputs.status == 'posted' }}
         continue-on-error: true
         env:
           GH_TOKEN: ${{ steps.target-read-token.outputs.token }}
@@ -1465,7 +1448,7 @@ jobs:
           exit 1
 
       - name: Release unsuccessful workflow-owned review lease
-        if: ${{ always() && steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.reserve-exact-review-lease.outputs.status != 'held' && steps.direct-exact-review-publication.outputs.accepted != 'true' && steps.queue-exact-review-publication.outcome != 'success' }}
+        if: ${{ always() && steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.live-item.outputs.proceed == 'true' && steps.checkout-target.outputs.source_drift != 'true' && steps.reserve-exact-review-lease.outputs.status != 'held' && steps.direct-exact-review-publication.outputs.accepted != 'true' && steps.queue-exact-review-publication.outcome != 'success' }}
         env:
           GH_TOKEN: ${{ steps.target-write-token.outputs.token }}
           TARGET_REPO: ${{ steps.target.outputs.target_repo }}
diff --git a/CHANGELOG.md b/CHANGELOG.md
index edd353ad1b..28a58730d3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@ checkpoint, and status-only commits are intentionally omitted.
 
 ### Changed
 
+- Exact pull-request reviews now materialize and verify the leased head through a tested TypeScript guard, requeue moved heads without running review or lease cleanup, and materialize sibling Codex source for OpenClaw contract review.
 - Event-review artifact publication completes as a superseded no-op when the reviewed branch vanished upstream (force-push or deletion) instead of failing the run.
 - Worker record requests now retry transient blank/invalid 2xx bodies from the edge within the bounded budget instead of failing hydration on the first occurrence.
 - Exact reviews of items that closed after enqueue now complete as superseded no-ops, and GitHub-throttled reservations defer as held retries — neither spends the item's review-failure budget.
diff --git a/package.json b/package.json
index 9b5343920b..712199736a 100644
--- a/package.json
+++ b/package.json
@@ -62,6 +62,7 @@
     "repair:spam-comment-intake": "node dist/repair/spam-comment-intake.js",
     "repair:spam-scan": "node dist/repair/spam-scanner.js",
     "repair:exact-review-bundle": "node dist/repair/exact-review-bundle-cli.js",
+    "repair:exact-review-source": "node dist/repair/exact-review-source-cli.js",
     "repair:exact-review-queue-maintenance": "node dist/repair/exact-review-queue-maintenance.js",
     "repair:scheduled-review-enqueue": "node dist/repair/scheduled-review-enqueue.js",
     "repair:exact-review-dead-letters": "node scripts/exact-review-dead-letter-operator.mjs",
diff --git a/src/repair/exact-review-source-cli.ts b/src/repair/exact-review-source-cli.ts
new file mode 100644
index 0000000000..4d6c936472
--- /dev/null
+++ b/src/repair/exact-review-source-cli.ts
@@ -0,0 +1,71 @@
+#!/usr/bin/env node
+import fs from "node:fs";
+
+import { materializeExactReviewSource } from "./exact-review-source.js";
+
+const args = parseArgs(process.argv.slice(2));
+const result = materializeExactReviewSource({
+  targetDir: required(args.targetDir, "--target-dir"),
+  itemKind: itemKind(required(args.itemKind, "--item-kind")),
+  itemNumber: positiveInteger(required(args.itemNumber, "--item-number"), "--item-number"),
+  ...(args.sourceHeadSha ? { sourceHeadSha: args.sourceHeadSha } : {}),
+});
+
+writeOutput("status", result.status);
+writeOutput("source_drift", result.status === "source_drift" ? "true" : "false");
+if (result.status === "source_drift") {
+  writeOutput("fetched_head_sha", result.fetchedHeadSha);
+  console.error(
+    `Fetched PR head ${result.fetchedHeadSha} moved past leased source head ${result.leasedHeadSha}; skipping review so the durable queue can requeue the latest source.`,
+  );
+} else {
+  writeOutput("materialized_head_sha", result.headSha);
+  console.log(result.headSha.slice(0, 12));
+}
+
+function parseArgs(argv: readonly string[]) {
+  const parsed: {
+    targetDir?: string;
+    itemKind?: string;
+    itemNumber?: string;
+    sourceHeadSha?: string;
+  } = {};
+  for (let index = 0; index < argv.length; index += 1) {
+    const flag = argv[index];
+    const value = argv[index + 1];
+    if (value === undefined || (flag !== "--source-head-sha" && value.startsWith("--"))) {
+      throw new Error(`${flag} requires a value`);
+    }
+    if (flag === "--target-dir") parsed.targetDir = value;
+    else if (flag === "--item-kind") parsed.itemKind = value;
+    else if (flag === "--item-number") parsed.itemNumber = value;
+    else if (flag === "--source-head-sha") parsed.sourceHeadSha = value;
+    else throw new Error(`unknown argument: ${flag}`);
+    index += 1;
+  }
+  return parsed;
+}
+
+function required(value: string | undefined, flag: string): string {
+  if (!value) throw new Error(`${flag} is required`);
+  return value;
+}
+
+function itemKind(value: string): "issue" | "pull_request" {
+  if (value === "issue" || value === "pull_request") return value;
+  throw new Error("--item-kind must be issue or pull_request");
+}
+
+function positiveInteger(value: string, flag: string): number {
+  const parsed = Number(value);
+  if (!Number.isSafeInteger(parsed) || parsed < 1) {
+    throw new Error(`${flag} must be a positive integer`);
+  }
+  return parsed;
+}
+
+function writeOutput(name: string, value: string): void {
+  const outputPath = process.env.GITHUB_OUTPUT;
+  if (outputPath) fs.appendFileSync(outputPath, `${name}=${value}\n`, "utf8");
+  else console.log(`${name}=${value}`);
+}
diff --git a/src/repair/exact-review-source.ts b/src/repair/exact-review-source.ts
new file mode 100644
index 0000000000..390441c7e6
--- /dev/null
+++ b/src/repair/exact-review-source.ts
@@ -0,0 +1,61 @@
+import { currentHead } from "./git-repo-utils.js";
+import { runCommand as run } from "./command-runner.js";
+
+const gitNetworkTimeoutMs = Math.max(
+  30_000,
+  Number(
+    process.env.CLAWSWEEPER_GIT_NETWORK_TIMEOUT_MS ??
+      process.env.CLAWSWEEPER_NETWORK_COMMAND_TIMEOUT_MS ??
+      5 * 60 * 1000,
+  ),
+);
+
+export type ExactReviewSourceResult =
+  | { status: "ready"; headSha: string }
+  | { status: "source_drift"; leasedHeadSha: string; fetchedHeadSha: string };
+
+export function materializeExactReviewSource(options: {
+  targetDir: string;
+  itemKind: "issue" | "pull_request";
+  itemNumber: number;
+  sourceHeadSha?: string;
+}): ExactReviewSourceResult {
+  if (!Number.isSafeInteger(options.itemNumber) || options.itemNumber < 1) {
+    throw new Error("itemNumber must be a positive integer");
+  }
+  if (options.itemKind === "issue") {
+    return { status: "ready", headSha: currentHead(options.targetDir) };
+  }
+
+  const leasedHeadSha = String(options.sourceHeadSha ?? "")
+    .trim()
+    .toLowerCase();
+  if (!/^[0-9a-f]{40}$/.test(leasedHeadSha)) {
+    throw new Error("Exact PR review requires a valid leased source head SHA");
+  }
+
+  run("git", ["fetch", "--force", "--depth=50", "origin", `refs/pull/${options.itemNumber}/head`], {
+    cwd: options.targetDir,
+    timeoutMs: gitNetworkTimeoutMs,
+  });
+  const fetchedHeadSha = run("git", ["rev-parse", "FETCH_HEAD"], {
+    cwd: options.targetDir,
+  })
+    .trim()
+    .toLowerCase();
+  if (!/^[0-9a-f]{40}$/.test(fetchedHeadSha)) {
+    throw new Error(`Fetched PR head is not a full commit SHA: ${fetchedHeadSha || "empty"}`);
+  }
+  if (fetchedHeadSha !== leasedHeadSha) {
+    return { status: "source_drift", leasedHeadSha, fetchedHeadSha };
+  }
+
+  run("git", ["checkout", "--detach", leasedHeadSha], { cwd: options.targetDir });
+  const headSha = currentHead(options.targetDir).toLowerCase();
+  if (headSha !== leasedHeadSha) {
+    throw new Error(
+      `Target checkout head ${headSha || "empty"} does not match leased source head ${leasedHeadSha}`,
+    );
+  }
+  return { status: "ready", headSha };
+}
diff --git a/test/repair/exact-review-source.test.ts b/test/repair/exact-review-source.test.ts
new file mode 100644
index 0000000000..068154646d
--- /dev/null
+++ b/test/repair/exact-review-source.test.ts
@@ -0,0 +1,115 @@
+import assert from "node:assert/strict";
+import { execFileSync } from "node:child_process";
+import { existsSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import test from "node:test";
+
+import { materializeExactReviewSource } from "../../dist/repair/exact-review-source.js";
+
+function git(args: string[], cwd?: string): string {
+  return execFileSync("git", args, {
+    ...(cwd ? { cwd } : {}),
+    encoding: "utf8",
+    stdio: ["ignore", "pipe", "pipe"],
+  }).trim();
+}
+
+function createPullFixture() {
+  const root = mkdtempSync(join(tmpdir(), "exact-review-source-"));
+  const origin = join(root, "origin.git");
+  const source = join(root, "source");
+  const target = join(root, "target");
+
+  git(["init", "--bare", origin]);
+  git(["init", source]);
+  git(["config", "user.email", "clawsweeper@example.com"], source);
+  git(["config", "user.name", "ClawSweeper Test"], source);
+  writeFileSync(join(source, "README.md"), "base\n");
+  git(["add", "README.md"], source);
+  git(["commit", "-m", "base"], source);
+  git(["branch", "-M", "main"], source);
+  git(["remote", "add", "origin", origin], source);
+  git(["push", "origin", "main"], source);
+
+  writeFileSync(join(source, "feature.txt"), "first\n");
+  git(["add", "feature.txt"], source);
+  git(["commit", "-m", "feature"], source);
+  const leasedHeadSha = git(["rev-parse", "HEAD"], source);
+  git(["push", "origin", "HEAD:refs/pull/357/head"], source);
+  git(["clone", "--branch", "main", origin, target]);
+
+  return { root, origin, source, target, leasedHeadSha };
+}
+
+test("materializes the immutable leased pull request head", () => {
+  const fixture = createPullFixture();
+  try {
+    assert.deepEqual(
+      materializeExactReviewSource({
+        targetDir: fixture.target,
+        itemKind: "pull_request",
+        itemNumber: 357,
+        sourceHeadSha: fixture.leasedHeadSha,
+      }),
+      { status: "ready", headSha: fixture.leasedHeadSha },
+    );
+    assert.equal(git(["rev-parse", "HEAD"], fixture.target), fixture.leasedHeadSha);
+    assert.equal(git(["rev-parse", "--abbrev-ref", "HEAD"], fixture.target), "HEAD");
+    assert.equal(readFileSync(join(fixture.target, "feature.txt"), "utf8"), "first\n");
+  } finally {
+    rmSync(fixture.root, { recursive: true, force: true });
+  }
+});
+
+test("reports source drift without checking out the moved pull request head", () => {
+  const fixture = createPullFixture();
+  try {
+    const originalCheckoutHead = git(["rev-parse", "HEAD"], fixture.target);
+    writeFileSync(join(fixture.source, "feature.txt"), "second\n");
+    git(["add", "feature.txt"], fixture.source);
+    git(["commit", "-m", "move head"], fixture.source);
+    const fetchedHeadSha = git(["rev-parse", "HEAD"], fixture.source);
+    git(["push", "--force", "origin", "HEAD:refs/pull/357/head"], fixture.source);
+
+    assert.deepEqual(
+      materializeExactReviewSource({
+        targetDir: fixture.target,
+        itemKind: "pull_request",
+        itemNumber: 357,
+        sourceHeadSha: fixture.leasedHeadSha,
+      }),
+      {
+        status: "source_drift",
+        leasedHeadSha: fixture.leasedHeadSha,
+        fetchedHeadSha,
+      },
+    );
+    assert.equal(git(["rev-parse", "HEAD"], fixture.target), originalCheckoutHead);
+    assert.equal(existsSync(join(fixture.target, "feature.txt")), false);
+  } finally {
+    rmSync(fixture.root, { recursive: true, force: true });
+  }
+});
+
+test("fails closed when the pull request ref cannot be fetched", () => {
+  const root = mkdtempSync(join(tmpdir(), "exact-review-source-missing-"));
+  const origin = join(root, "origin.git");
+  const target = join(root, "target");
+  try {
+    git(["init", "--bare", origin]);
+    git(["clone", origin, target]);
+    assert.throws(
+      () =>
+        materializeExactReviewSource({
+          targetDir: target,
+          itemKind: "pull_request",
+          itemNumber: 357,
+          sourceHeadSha: "a".repeat(40),
+        }),
+      /couldn't find remote ref|could not read from remote repository|fatal:/i,
+    );
+  } finally {
+    rmSync(root, { recursive: true, force: true });
+  }
+});
diff --git a/test/sweep-workflow.test.ts b/test/sweep-workflow.test.ts
index 0d7658ae93..8a7dfaf10e 100644
--- a/test/sweep-workflow.test.ts
+++ b/test/sweep-workflow.test.ts
@@ -3594,9 +3594,13 @@ test("sweep workflow schedules cursor-based PR comment sync batches", () => {
 });
 
 test("sweep target checkouts retry without cached references", () => {
-  const workflow = readText(".github/workflows/sweep.yml");
-  const checkoutBlocks =
-    workflow.match(/- name: Check out target repository[\s\S]*?rev-parse --short HEAD/g) ?? [];
+  const workflow = YAML.parse(readText(".github/workflows/sweep.yml")) as {
+    jobs: Record<string, { steps?: Array<{ name?: string; run?: string }> }>;
+  };
+  const checkoutBlocks = Object.values(workflow.jobs)
+    .flatMap((job) => job.steps ?? [])
+    .filter((step) => step.name === "Check out target repository")
+    .map((step) => step.run ?? "");
 
   assert.equal(checkoutBlocks.length, 2);
   for (const block of checkoutBlocks) {
@@ -3642,12 +3646,7 @@ test("exact PR reviews fail closed unless the leased source head is checked out"
     checkout.env?.SOURCE_HEAD_SHA,
     "${{ fromJSON(steps.claim-exact-review-queue.outputs.decision).sourceHeadSha || '' }}",
   );
-  assert.match(checkout.run ?? "", /refs\/pull\/\$\{ITEM_NUMBER\}\/head/);
-  assert.match(checkout.run ?? "", /fetched_head" != "\$SOURCE_HEAD_SHA/);
-  assert.match(checkout.run ?? "", /source_drift=true/);
-  assert.match(checkout.run ?? "", /exit 0/);
-  assert.match(checkout.run ?? "", /checkout --detach "\$SOURCE_HEAD_SHA"/);
-  assert.match(checkout.run ?? "", /checked_out_head" != "\$SOURCE_HEAD_SHA/);
+  assert.match(checkout.run ?? "", /repair:exact-review-source/);
   assert.equal(
     requeue.if,
     "${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.checkout-target.outputs.source_drift == 'true' }}",
@@ -3661,6 +3660,18 @@ test("exact PR reviews fail closed unless the leased source head is checked out"
   );
   assert.match(generation.run ?? "", /SOURCE_DRIFT" = "true"/);
   assert.match(generation.run ?? "", /requeue_latest=true/);
+
+  for (const name of [
+    "Reserve exact review lease",
+    "Review exact event item",
+    "Finalize exact event action ledger",
+    "Create exact review artifact bundle",
+    "Release unsuccessful workflow-owned review lease",
+  ]) {
+    const step = steps.find((candidate) => candidate.name === name);
+    assert.ok(step, `missing ${name}`);
+    assert.match(step.if ?? "", /checkout-target\.outputs\.source_drift != 'true'/);
+  }
 });
 
 test("scheduled OpenClaw review workers materialize sibling Codex source", () => {

From 813167fd14590cbfa5ae5a65dcdace44e815647a Mon Sep 17 00:00:00 2001
From: Vincent Koc <vincentkoc@ieee.org>
Date: Fri, 31 Jul 2026 22:48:47 +0200
Subject: [PATCH 3/3] fix(review): preserve exact review ancestry

---
 .github/workflows/sweep.yml             |  1 +
 CHANGELOG.md                            |  2 +-
 src/repair/exact-review-source-cli.ts   |  6 ++-
 src/repair/exact-review-source.ts       | 10 ++++-
 test/repair/exact-review-source.test.ts | 59 ++++++++++++++++++++++---
 test/sweep-workflow.test.ts             |  1 +
 6 files changed, 68 insertions(+), 11 deletions(-)

diff --git a/.github/workflows/sweep.yml b/.github/workflows/sweep.yml
index 5af7f25a6b..c238dcd072 100644
--- a/.github/workflows/sweep.yml
+++ b/.github/workflows/sweep.yml
@@ -896,6 +896,7 @@ jobs:
             --target-dir "$checkout_dir" \
             --item-kind "$ITEM_KIND" \
             --item-number "$ITEM_NUMBER" \
+            --base-branch "$target_branch" \
             --source-head-sha "$SOURCE_HEAD_SHA"
 
       - name: Requeue exact review after source drift
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 28a58730d3..7b66e038d8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,7 +18,7 @@ checkpoint, and status-only commits are intentionally omitted.
 
 ### Changed
 
-- Exact pull-request reviews now materialize and verify the leased head through a tested TypeScript guard, requeue moved heads without running review or lease cleanup, and materialize sibling Codex source for OpenClaw contract review.
+- Exact pull-request reviews now materialize and verify the leased head with complete merge-base ancestry through a tested TypeScript guard, requeue moved heads without running review or lease cleanup, and materialize sibling Codex source for OpenClaw contract review.
 - Event-review artifact publication completes as a superseded no-op when the reviewed branch vanished upstream (force-push or deletion) instead of failing the run.
 - Worker record requests now retry transient blank/invalid 2xx bodies from the edge within the bounded budget instead of failing hydration on the first occurrence.
 - Exact reviews of items that closed after enqueue now complete as superseded no-ops, and GitHub-throttled reservations defer as held retries — neither spends the item's review-failure budget.
diff --git a/src/repair/exact-review-source-cli.ts b/src/repair/exact-review-source-cli.ts
index 4d6c936472..fb83fc52f5 100644
--- a/src/repair/exact-review-source-cli.ts
+++ b/src/repair/exact-review-source-cli.ts
@@ -4,10 +4,12 @@ import fs from "node:fs";
 import { materializeExactReviewSource } from "./exact-review-source.js";
 
 const args = parseArgs(process.argv.slice(2));
+const kind = itemKind(required(args.itemKind, "--item-kind"));
 const result = materializeExactReviewSource({
   targetDir: required(args.targetDir, "--target-dir"),
-  itemKind: itemKind(required(args.itemKind, "--item-kind")),
+  itemKind: kind,
   itemNumber: positiveInteger(required(args.itemNumber, "--item-number"), "--item-number"),
+  ...(kind === "pull_request" ? { baseBranch: required(args.baseBranch, "--base-branch") } : {}),
   ...(args.sourceHeadSha ? { sourceHeadSha: args.sourceHeadSha } : {}),
 });
 
@@ -28,6 +30,7 @@ function parseArgs(argv: readonly string[]) {
     targetDir?: string;
     itemKind?: string;
     itemNumber?: string;
+    baseBranch?: string;
     sourceHeadSha?: string;
   } = {};
   for (let index = 0; index < argv.length; index += 1) {
@@ -39,6 +42,7 @@ function parseArgs(argv: readonly string[]) {
     if (flag === "--target-dir") parsed.targetDir = value;
     else if (flag === "--item-kind") parsed.itemKind = value;
     else if (flag === "--item-number") parsed.itemNumber = value;
+    else if (flag === "--base-branch") parsed.baseBranch = value;
     else if (flag === "--source-head-sha") parsed.sourceHeadSha = value;
     else throw new Error(`unknown argument: ${flag}`);
     index += 1;
diff --git a/src/repair/exact-review-source.ts b/src/repair/exact-review-source.ts
index 390441c7e6..cc134ad4b9 100644
--- a/src/repair/exact-review-source.ts
+++ b/src/repair/exact-review-source.ts
@@ -1,4 +1,4 @@
-import { currentHead } from "./git-repo-utils.js";
+import { currentHead, ensureMergeBaseAvailable } from "./git-repo-utils.js";
 import { runCommand as run } from "./command-runner.js";
 
 const gitNetworkTimeoutMs = Math.max(
@@ -18,6 +18,7 @@ export function materializeExactReviewSource(options: {
   targetDir: string;
   itemKind: "issue" | "pull_request";
   itemNumber: number;
+  baseBranch?: string;
   sourceHeadSha?: string;
 }): ExactReviewSourceResult {
   if (!Number.isSafeInteger(options.itemNumber) || options.itemNumber < 1) {
@@ -33,8 +34,12 @@ export function materializeExactReviewSource(options: {
   if (!/^[0-9a-f]{40}$/.test(leasedHeadSha)) {
     throw new Error("Exact PR review requires a valid leased source head SHA");
   }
+  const baseBranch = String(options.baseBranch ?? "").trim();
+  if (!baseBranch) {
+    throw new Error("Exact PR review requires its base branch");
+  }
 
-  run("git", ["fetch", "--force", "--depth=50", "origin", `refs/pull/${options.itemNumber}/head`], {
+  run("git", ["fetch", "--force", "origin", `refs/pull/${options.itemNumber}/head`], {
     cwd: options.targetDir,
     timeoutMs: gitNetworkTimeoutMs,
   });
@@ -57,5 +62,6 @@ export function materializeExactReviewSource(options: {
       `Target checkout head ${headSha || "empty"} does not match leased source head ${leasedHeadSha}`,
     );
   }
+  ensureMergeBaseAvailable({ targetDir: options.targetDir, baseBranch });
   return { status: "ready", headSha };
 }
diff --git a/test/repair/exact-review-source.test.ts b/test/repair/exact-review-source.test.ts
index 068154646d..0a38b1e6b9 100644
--- a/test/repair/exact-review-source.test.ts
+++ b/test/repair/exact-review-source.test.ts
@@ -15,7 +15,10 @@ function git(args: string[], cwd?: string): string {
   }).trim();
 }
 
-function createPullFixture() {
+function createPullFixture(
+  featureCommitCount = 1,
+  options: { baseAdvanceCount?: number; shallowTarget?: boolean } = {},
+) {
   const root = mkdtempSync(join(tmpdir(), "exact-review-source-"));
   const origin = join(root, "origin.git");
   const source = join(root, "source");
@@ -28,18 +31,36 @@ function createPullFixture() {
   writeFileSync(join(source, "README.md"), "base\n");
   git(["add", "README.md"], source);
   git(["commit", "-m", "base"], source);
+  const baseSha = git(["rev-parse", "HEAD"], source);
   git(["branch", "-M", "main"], source);
   git(["remote", "add", "origin", origin], source);
   git(["push", "origin", "main"], source);
 
-  writeFileSync(join(source, "feature.txt"), "first\n");
-  git(["add", "feature.txt"], source);
-  git(["commit", "-m", "feature"], source);
+  for (let index = 1; index <= featureCommitCount; index += 1) {
+    writeFileSync(join(source, "feature.txt"), `feature ${index}\n`);
+    git(["add", "feature.txt"], source);
+    git(["commit", "-m", `feature ${index}`], source);
+  }
   const leasedHeadSha = git(["rev-parse", "HEAD"], source);
   git(["push", "origin", "HEAD:refs/pull/357/head"], source);
-  git(["clone", "--branch", "main", origin, target]);
+  if ((options.baseAdvanceCount ?? 0) > 0) {
+    git(["checkout", "-B", "advanced-main", baseSha], source);
+    for (let index = 1; index <= (options.baseAdvanceCount ?? 0); index += 1) {
+      writeFileSync(join(source, "README.md"), `base ${index}\n`);
+      git(["add", "README.md"], source);
+      git(["commit", "-m", `base ${index}`], source);
+    }
+    git(["push", "origin", "HEAD:main"], source);
+  }
+  git([
+    "clone",
+    "--branch",
+    "main",
+    ...(options.shallowTarget ? ["--depth=1", `file://${origin}`] : [origin]),
+    target,
+  ]);
 
-  return { root, origin, source, target, leasedHeadSha };
+  return { root, origin, source, target, baseSha, leasedHeadSha };
 }
 
 test("materializes the immutable leased pull request head", () => {
@@ -50,13 +71,35 @@ test("materializes the immutable leased pull request head", () => {
         targetDir: fixture.target,
         itemKind: "pull_request",
         itemNumber: 357,
+        baseBranch: "main",
         sourceHeadSha: fixture.leasedHeadSha,
       }),
       { status: "ready", headSha: fixture.leasedHeadSha },
     );
     assert.equal(git(["rev-parse", "HEAD"], fixture.target), fixture.leasedHeadSha);
     assert.equal(git(["rev-parse", "--abbrev-ref", "HEAD"], fixture.target), "HEAD");
-    assert.equal(readFileSync(join(fixture.target, "feature.txt"), "utf8"), "first\n");
+    assert.equal(readFileSync(join(fixture.target, "feature.txt"), "utf8"), "feature 1\n");
+  } finally {
+    rmSync(fixture.root, { recursive: true, force: true });
+  }
+});
+
+test("materializes both sides of deep pull request ancestry from a shallow base", () => {
+  const fixture = createPullFixture(75, { baseAdvanceCount: 60, shallowTarget: true });
+  try {
+    assert.deepEqual(
+      materializeExactReviewSource({
+        targetDir: fixture.target,
+        itemKind: "pull_request",
+        itemNumber: 357,
+        baseBranch: "main",
+        sourceHeadSha: fixture.leasedHeadSha,
+      }),
+      { status: "ready", headSha: fixture.leasedHeadSha },
+    );
+    assert.equal(git(["merge-base", "origin/main", "HEAD"], fixture.target), fixture.baseSha);
+    assert.equal(git(["rev-list", "--count", "origin/main..HEAD"], fixture.target), "75");
+    assert.equal(git(["rev-parse", "--is-shallow-repository"], fixture.target), "false");
   } finally {
     rmSync(fixture.root, { recursive: true, force: true });
   }
@@ -77,6 +120,7 @@ test("reports source drift without checking out the moved pull request head", ()
         targetDir: fixture.target,
         itemKind: "pull_request",
         itemNumber: 357,
+        baseBranch: "main",
         sourceHeadSha: fixture.leasedHeadSha,
       }),
       {
@@ -105,6 +149,7 @@ test("fails closed when the pull request ref cannot be fetched", () => {
           targetDir: target,
           itemKind: "pull_request",
           itemNumber: 357,
+          baseBranch: "main",
           sourceHeadSha: "a".repeat(40),
         }),
       /couldn't find remote ref|could not read from remote repository|fatal:/i,
diff --git a/test/sweep-workflow.test.ts b/test/sweep-workflow.test.ts
index 8a7dfaf10e..adc1a76723 100644
--- a/test/sweep-workflow.test.ts
+++ b/test/sweep-workflow.test.ts
@@ -3647,6 +3647,7 @@ test("exact PR reviews fail closed unless the leased source head is checked out"
     "${{ fromJSON(steps.claim-exact-review-queue.outputs.decision).sourceHeadSha || '' }}",
   );
   assert.match(checkout.run ?? "", /repair:exact-review-source/);
+  assert.match(checkout.run ?? "", /--base-branch "\$target_branch"/);
   assert.equal(
     requeue.if,
     "${{ steps.claim-exact-review-queue.outputs.claimed == 'true' && steps.checkout-target.outputs.source_drift == 'true' }}",