diff --git a/.github/scripts/tests/notify-pr-merge-review.test.mjs b/.github/scripts/tests/notify-pr-merge-review.test.mjs
index dbb8dca94d..aadd27bea6 100644
--- a/.github/scripts/tests/notify-pr-merge-review.test.mjs
+++ b/.github/scripts/tests/notify-pr-merge-review.test.mjs
@@ -253,6 +253,58 @@ test("workflow uses read permissions, a protected environment, trusted checkout,
   }
 });
 
+// Evaluates the small GitHub expression subset used by the notifier job condition.
+// Unknown functions or syntax fail the test instead of being silently approximated.
+function jobCondition(expression) {
+  const source = expression.trim().replace(/\s+/g, " ");
+  const allowed = /^(?:\s|\(|\)|&&|\|\||==|!=|,|'[^']*'|\d+|github(?:\.[a-z_]+)+|contains|fromJSON)+$/;
+  assert.match(source, allowed, "Unsupported syntax in the notifier job condition");
+  const javascript = source.replace(/github((?:\.[a-z_]+)+)/g, (_, path) => `github${path.replaceAll(".", "?.")}`)
+    .replace(/==/g, "===").replace(/!===/g, "!==");
+  const evaluate = new Function("github", "contains", "fromJSON", `return (${javascript});`);
+  return (github) => evaluate(github, (list, value) => list.includes(value), (text) => JSON.parse(text));
+}
+
+test("workflow skips non-final events before runner allocation and collapses bursts per PR head", () => {
+  const workflow = readFileSync(".github/workflows/pr-merge-review.yml", "utf8");
+  const triggers = workflow.slice(workflow.indexOf("\non:"), workflow.indexOf("\npermissions:"));
+  // Exactly these trigger kinds; check_run and status cannot be filtered at the trigger level.
+  assert.deepEqual([...triggers.matchAll(/^ {2}([a-z_]+):/gm)].map((match) => match[1]),
+    ["workflow_run", "check_run", "status"]);
+  assert.match(triggers, /check_run:\n {4}types: \[completed\]/);
+  const job = workflow.slice(workflow.indexOf("\n  notify:"));
+  const condition = job.slice(job.indexOf("    if: >-"), job.indexOf("\n    # ", job.indexOf("    if: >-")));
+  // GitHub Actions check runs arrive through workflow_run; only other providers schedule a job.
+  assert.match(condition, /github\.event_name == 'check_run' &&\s+github\.event\.check_run\.app\.id != 15368/);
+  assert.match(condition, /fromJSON\('\["success","skipped","neutral"\]'\), github\.event\.check_run\.conclusion/);
+  assert.match(condition, /fromJSON\('\["success","skipped","neutral"\]'\), github\.event\.workflow_run\.conclusion/);
+  assert.match(condition, /github\.event_name == 'status' && github\.event\.state == 'success'/);
+  assert.match(condition, /github\.event\.workflow_run\.event == 'pull_request'/);
+  assert.match(condition, /github\.repository == 'paperclipai\/paperclip'/);
+  // Evaluate the condition for real events so an operator change cannot reopen the flood.
+  const schedules = jobCondition(condition.replace(/^ {4}if: >-/, ""));
+  const repository = { full_name: "paperclipai/paperclip" };
+  const run = (event, conclusion) => ({ event_name: "workflow_run", repository: "paperclipai/paperclip",
+    event: { repository, workflow_run: { event, conclusion, head_sha: head } } });
+  const checkRun = (appId, conclusion) => ({ event_name: "check_run", repository: "paperclipai/paperclip",
+    event: { repository, check_run: { app: { id: appId }, conclusion, head_sha: head } } });
+  const status = (state) => ({ event_name: "status", repository: "paperclipai/paperclip",
+    event: { repository, state, sha: head } });
+  for (const accepted of [run("pull_request", "success"), run("pull_request_target", "neutral"),
+    run("pull_request", "skipped"), checkRun(867647, "success"), checkRun(156372, "neutral"), status("success")]) {
+    assert.equal(schedules(accepted), true, JSON.stringify(accepted));
+  }
+  for (const rejected of [run("pull_request", "failure"), run("pull_request", "cancelled"), run("push", "success"),
+    run("schedule", "success"), checkRun(15368, "success"), checkRun(867647, "failure"),
+    checkRun(867647, "action_required"), status("pending"), status("failure"), status("error"),
+    { ...status("success"), repository: "someone/fork" }]) {
+    assert.equal(schedules(rejected), false, JSON.stringify(rejected));
+  }
+  // Job-level concurrency: a skipped event must not cancel a scheduled notifier.
+  assert.doesNotMatch(workflow.slice(0, workflow.indexOf("\njobs:")), /concurrency:/);
+  assert.match(job, /\n {4}concurrency:\n {6}group: pr-merge-review-\$\{\{ github\.event\.workflow_run\.head_sha \|\| github\.event\.check_run\.head_sha \|\| github\.event\.sha \}\}\n {6}cancel-in-progress: true\n/);
+});
+
 test("API probe uses the same read permissions without private webhook access", () => {
   const probe = readFileSync(".github/workflows/pr-review-api-access.yml", "utf8");
   for (const permission of ["actions", "checks", "contents", "pull-requests", "statuses"]) {
diff --git a/.github/workflows/pr-merge-review.yml b/.github/workflows/pr-merge-review.yml
index 87c08abbc4..827bf28f4e 100644
--- a/.github/workflows/pr-merge-review.yml
+++ b/.github/workflows/pr-merge-review.yml
@@ -16,6 +16,9 @@ on:
       - PR review API access
     types: [completed]
   # External check providers and legacy commit statuses can finish after CI.
+  # GitHub has no trigger-level filter for these events, so the job condition
+  # below skips them before a runner is allocated. GitHub Actions check runs
+  # are covered by the workflow_run list above.
   check_run:
     types: [completed]
   status:
@@ -29,11 +32,27 @@ permissions:
 
 jobs:
   notify:
+    # A skipped job does not take a runner. Only events that can complete a
+    # green PR state schedule the job: successful, skipped, or neutral PR
+    # workflow runs, the same results from non-Actions check providers (GitHub
+    # Actions app 15368 checks arrive through workflow_run), and successful
+    # commit statuses. One PR push previously queued about 60 runner jobs.
     if: >-
       github.repository == 'paperclipai/paperclip' &&
-      (github.event_name != 'workflow_run' ||
-        github.event.workflow_run.event == 'pull_request' ||
-        github.event.workflow_run.event == 'pull_request_target')
+      ((github.event_name == 'workflow_run' &&
+        (github.event.workflow_run.event == 'pull_request' ||
+          github.event.workflow_run.event == 'pull_request_target') &&
+        contains(fromJSON('["success","skipped","neutral"]'), github.event.workflow_run.conclusion)) ||
+      (github.event_name == 'check_run' &&
+        github.event.check_run.app.id != 15368 &&
+        contains(fromJSON('["success","skipped","neutral"]'), github.event.check_run.conclusion)) ||
+      (github.event_name == 'status' && github.event.state == 'success'))
+    # Collapse bursts for one PR head to the latest event. The notifier reads
+    # the current PR state, so the newest event subsumes older ones. Job-level
+    # concurrency keeps skipped events from cancelling a scheduled notifier.
+    concurrency:
+      group: pr-merge-review-${{ github.event.workflow_run.head_sha || github.event.check_run.head_sha || github.event.sha }}
+      cancel-in-progress: true
     runs-on: ubuntu-latest
     timeout-minutes: 5
     # Restrict this environment to master. Repository secrets would also be
diff --git a/doc/PR-MERGE-REVIEW-WEBHOOK.md b/doc/PR-MERGE-REVIEW-WEBHOOK.md
index 6526aca099..664a2b7886 100644
--- a/doc/PR-MERGE-REVIEW-WEBHOOK.md
+++ b/doc/PR-MERGE-REVIEW-WEBHOOK.md
@@ -34,6 +34,15 @@ PR code or downloads PR artifacts or caches. It reacts to the repository's PR
 workflow completions, external check completions, and legacy commit statuses.
 When adding another PR verification workflow, add its name to `workflow_run`.
 
+GitHub cannot filter `check_run` or `status` triggers, so the job condition
+skips events that cannot complete a green state before a runner is allocated.
+Only successful, skipped, or neutral PR workflow runs and non-Actions check runs,
+and successful commit statuses, schedule the job. GitHub Actions check runs are
+skipped because their workflow completions already arrive through `workflow_run`.
+A job-level concurrency group keyed by the PR head SHA cancels older pending or
+running notifiers, because the newest event sees the most complete PR state.
+The group is on the job so skipped events cannot cancel a scheduled notifier.
+
 The separate `PR review API access` workflow checks notifier changes using
 the real read-only Actions token. It has no private environment or webhook
 credentials and sends no webhook. Both workflows explicitly grant