diff --git a/.github/workflows/server-parity.yml b/.github/workflows/server-parity.yml
index 842c1c9c2..f334e226e 100644
--- a/.github/workflows/server-parity.yml
+++ b/.github/workflows/server-parity.yml
@@ -64,6 +64,7 @@ on:
       - tests/Unit/ServerParityLargeCommandBatchesContractTest.mjs
       - tests/Unit/ServerParityManyUpdatesContractTest.mjs
       - tests/Unit/ServerParityWorkerErrorBodiesContractTest.mjs
+      - tests/Unit/ServerParityChildDescriptionsContractTest.mjs
       - tests/Unit/ServerParityStartSearchAttributesContractTest.mjs
       - tests/Unit/ServerParityQueryArgumentsContractTest.mjs
       - tests/Unit/ServerParityQueryContractArgumentsContractTest.mjs
@@ -1990,7 +1991,7 @@ jobs:
           bash scripts/ci/run-composer.sh --rm -v "$PWD:/source" -w /source -- \
             install --working-dir=scripts/conformance/server-parity --no-interaction --no-progress
           docker run --rm --user=1000:1000 --entrypoint node -v "$PWD:/source:ro" -w /source \
-            "$image" --test tests/Unit/ServerParityRunnerTest.mjs tests/Unit/ServerParityRunnerBlockedExcerptTest.mjs tests/Unit/ServerParityProbeNotesTest.mjs tests/Unit/ServerParitySdkDirectionLanesTest.mjs tests/Unit/ServerParityCodecDeadlineCellsTest.mjs tests/Unit/ServerParityCooperativeContractTest.mjs tests/Unit/ServerParityChildCancellationContractTest.mjs tests/Unit/ServerParityScheduleContractTest.mjs tests/Unit/ServerParityVisibilityContractTest.mjs tests/Unit/ServerParityAdmissionContractTest.mjs tests/Unit/ServerParityRoleTokenContractTest.mjs tests/Unit/ServerParityWorkerDeregistrationContractTest.mjs tests/Unit/ServerParitySearchAttributeContractTest.mjs tests/Unit/ServerParityWorkerListingContractTest.mjs tests/Unit/ServerParityWorkerReplacementContractTest.mjs tests/Unit/ServerParityPatchDeploymentContractTest.mjs tests/Unit/ServerParityWaitingHistoryContractTest.mjs tests/Unit/ServerParityTaskRetryContractTest.mjs tests/Unit/ServerParityPublishedPatchContractTest.mjs tests/Unit/ServerParityPublishedPatchTransportTest.mjs tests/Unit/ServerParityRecordFileTest.mjs tests/Unit/ServerParityFailureLocationTest.mjs tests/Unit/ServerParityFailureExcerptTest.mjs tests/Unit/ServerParityLateWorkflowCompletionContractTest.mjs tests/Unit/ServerParityStorageTestContractTest.mjs tests/Unit/ServerParitySchedulePoliciesContractTest.mjs tests/Unit/ServerParitySignalsBeforeWorkerContractTest.mjs tests/Unit/ServerParityScheduleCatalogContractTest.mjs tests/Unit/ServerParityOperatorMetricsContractTest.mjs tests/Unit/ServerParityActivityLeaseRenewalContractTest.mjs tests/Unit/ServerParityConcurrentWaitsContractTest.mjs tests/Unit/ServerParityContinueTransfersContractTest.mjs tests/Unit/ServerParityWorkerErrorBodiesContractTest.mjs tests/Unit/ServerParityLargeCommandBatchesContractTest.mjs tests/Unit/ServerParityManyUpdatesContractTest.mjs tests/Unit/ServerParityStartSearchAttributesContractTest.mjs tests/Unit/ServerParityQueryArgumentsContractTest.mjs tests/Unit/ServerParityQueryContractArgumentsContractTest.mjs tests/Unit/ServerParityParentCloseCancellationContractTest.mjs tests/Unit/ServerParityRecordLocalActivityContractTest.mjs tests/Unit/ServerParityActivityCancellationAckContractTest.mjs tests/Unit/ServerParityServiceCatalogContractTest.mjs tests/Unit/ServerParityServiceEndpointsContractTest.mjs tests/Unit/ServerParityServiceCallsContractTest.mjs tests/Unit/ServerParityWorkflowImportContractTest.mjs tests/Unit/ServerParityWaterlineImportContractTest.mjs tests/Unit/ServerParitySystemMetricsContractTest.mjs tests/Unit/ServerParityOperatorDashboardTypesContractTest.mjs tests/Unit/ServerParityPrometheusMetricsContractTest.mjs tests/Unit/ServerParityPayloadCleanupContractTest.mjs tests/Unit/ServerParityRepairPassContractTest.mjs tests/Unit/ServerParityClusterInfoContractTest.mjs tests/Unit/ServerParityNamespaceDeleteContractTest.mjs tests/Unit/ServerParityMessageStreamsContractTest.mjs tests/Unit/ServerParityCancellationScopesContractTest.mjs tests/Unit/ServerParityWorkflowPollRequestContractTest.mjs tests/Unit/ServerParityUpdateValidationContractTest.mjs tests/Unit/ServerParityFixtureSelectionTest.mjs tests/Unit/ServerParityUpdateValidationRetryTest.mjs tests/Unit/ServerParityKilledAuthorPollTest.mjs tests/Unit/ServerParityImagePullTest.mjs tests/Unit/ServerParityAdapterCacheTest.mjs tests/Unit/ServerParityWorkerSessionsContractTest.mjs tests/Unit/ServerParityWorkerSessionActivitiesContractTest.mjs tests/Unit/ServerParityNexusOperationsContractTest.mjs tests/Unit/ServerParityBridgeAdaptersContractTest.mjs tests/Unit/ServerParityWorkflowStreamWritesContractTest.mjs > parity-evidence/comparator-tests.txt
+            "$image" --test tests/Unit/ServerParityRunnerTest.mjs tests/Unit/ServerParityRunnerBlockedExcerptTest.mjs tests/Unit/ServerParityProbeNotesTest.mjs tests/Unit/ServerParitySdkDirectionLanesTest.mjs tests/Unit/ServerParityCodecDeadlineCellsTest.mjs tests/Unit/ServerParityCooperativeContractTest.mjs tests/Unit/ServerParityChildCancellationContractTest.mjs tests/Unit/ServerParityScheduleContractTest.mjs tests/Unit/ServerParityVisibilityContractTest.mjs tests/Unit/ServerParityAdmissionContractTest.mjs tests/Unit/ServerParityRoleTokenContractTest.mjs tests/Unit/ServerParityWorkerDeregistrationContractTest.mjs tests/Unit/ServerParitySearchAttributeContractTest.mjs tests/Unit/ServerParityWorkerListingContractTest.mjs tests/Unit/ServerParityWorkerReplacementContractTest.mjs tests/Unit/ServerParityPatchDeploymentContractTest.mjs tests/Unit/ServerParityWaitingHistoryContractTest.mjs tests/Unit/ServerParityTaskRetryContractTest.mjs tests/Unit/ServerParityPublishedPatchContractTest.mjs tests/Unit/ServerParityPublishedPatchTransportTest.mjs tests/Unit/ServerParityRecordFileTest.mjs tests/Unit/ServerParityFailureLocationTest.mjs tests/Unit/ServerParityFailureExcerptTest.mjs tests/Unit/ServerParityLateWorkflowCompletionContractTest.mjs tests/Unit/ServerParityStorageTestContractTest.mjs tests/Unit/ServerParitySchedulePoliciesContractTest.mjs tests/Unit/ServerParitySignalsBeforeWorkerContractTest.mjs tests/Unit/ServerParityScheduleCatalogContractTest.mjs tests/Unit/ServerParityOperatorMetricsContractTest.mjs tests/Unit/ServerParityActivityLeaseRenewalContractTest.mjs tests/Unit/ServerParityConcurrentWaitsContractTest.mjs tests/Unit/ServerParityContinueTransfersContractTest.mjs tests/Unit/ServerParityChildDescriptionsContractTest.mjs tests/Unit/ServerParityWorkerErrorBodiesContractTest.mjs tests/Unit/ServerParityLargeCommandBatchesContractTest.mjs tests/Unit/ServerParityManyUpdatesContractTest.mjs tests/Unit/ServerParityStartSearchAttributesContractTest.mjs tests/Unit/ServerParityQueryArgumentsContractTest.mjs tests/Unit/ServerParityQueryContractArgumentsContractTest.mjs tests/Unit/ServerParityParentCloseCancellationContractTest.mjs tests/Unit/ServerParityRecordLocalActivityContractTest.mjs tests/Unit/ServerParityActivityCancellationAckContractTest.mjs tests/Unit/ServerParityServiceCatalogContractTest.mjs tests/Unit/ServerParityServiceEndpointsContractTest.mjs tests/Unit/ServerParityServiceCallsContractTest.mjs tests/Unit/ServerParityWorkflowImportContractTest.mjs tests/Unit/ServerParityWaterlineImportContractTest.mjs tests/Unit/ServerParitySystemMetricsContractTest.mjs tests/Unit/ServerParityOperatorDashboardTypesContractTest.mjs tests/Unit/ServerParityPrometheusMetricsContractTest.mjs tests/Unit/ServerParityPayloadCleanupContractTest.mjs tests/Unit/ServerParityRepairPassContractTest.mjs tests/Unit/ServerParityClusterInfoContractTest.mjs tests/Unit/ServerParityNamespaceDeleteContractTest.mjs tests/Unit/ServerParityMessageStreamsContractTest.mjs tests/Unit/ServerParityCancellationScopesContractTest.mjs tests/Unit/ServerParityWorkflowPollRequestContractTest.mjs tests/Unit/ServerParityUpdateValidationContractTest.mjs tests/Unit/ServerParityFixtureSelectionTest.mjs tests/Unit/ServerParityUpdateValidationRetryTest.mjs tests/Unit/ServerParityKilledAuthorPollTest.mjs tests/Unit/ServerParityImagePullTest.mjs tests/Unit/ServerParityAdapterCacheTest.mjs tests/Unit/ServerParityWorkerSessionsContractTest.mjs tests/Unit/ServerParityWorkerSessionActivitiesContractTest.mjs tests/Unit/ServerParityNexusOperationsContractTest.mjs tests/Unit/ServerParityBridgeAdaptersContractTest.mjs tests/Unit/ServerParityWorkflowStreamWritesContractTest.mjs > parity-evidence/comparator-tests.txt
           docker run --rm --user=1000:1000 --cpus=1 --memory=256m --memory-swap=256m \
             --network=none --entrypoint node -v "$PWD:/source:ro" -w /source \
             "$image" --test tests/Unit/ServerParityCodecDeadlineLoadTest.mjs > parity-evidence/codec-load-tests.txt
diff --git a/docs/rust-server-port-checkpoints/2026-10-29-child-descriptions.md b/docs/rust-server-port-checkpoints/2026-10-29-child-descriptions.md
new file mode 100644
index 000000000..c8ad1a56b
--- /dev/null
+++ b/docs/rust-server-port-checkpoints/2026-10-29-child-descriptions.md
@@ -0,0 +1,30 @@
+# October 29, descriptions with several open children
+
+- **Before.** Native's child summary (`child_summary.rs`), which describes a
+  parent waiting on children, gave up when:
+  - a second child was open while another was still waiting;
+  - a child's `parent_close_policy` was not `abandon`;
+  - more than 100 children had been started over the run's life;
+  - a timer wait was also open.
+
+  The parent was then described with no wait (`wait_kind` null).
+- **Contract** (published 2.11.5; `WorkflowController::show`, Workflow
+  2.15.1 `RunWaitView`): a parent is described by its open waits. With
+  several open children it waits for the first. An open timer is described
+  ahead of open children, whichever was scheduled first. The parent-close
+  policy does not change the description.
+- **Fixture.** `child-descriptions`, raw worker HTTP on protocol 1.20 in a
+  fresh namespace. Each case completes the parent's first workflow task with
+  its commands and records the answer and the description: one child, two
+  children, a child then a timer, a timer then a child, and a child under
+  `parent_close_policy: terminate`.
+- **Native.**
+  - The summary keeps any number of open children, with no lifetime cap.
+  - Any parent-close policy is allowed.
+  - When a timer wait is already chosen and every child is still open, the
+    timer stays the run's wait.
+- **Not covered here.** A child with a cancellation policy other than
+  `abandon` or with a retry or timeout policy, and a child beside an open
+  activity, are still described without their wait, pending evidence.
+- **Tests.** `child_descriptions.rs`. On the previous source, two children
+  and a child beside a timer were described with a null wait.
diff --git a/docs/rust-server-port.md b/docs/rust-server-port.md
index c1bf223ee..fc033800f 100644
--- a/docs/rust-server-port.md
+++ b/docs/rust-server-port.md
@@ -586,8 +586,18 @@ contract fixture before its correction.
   `many-updates` fixture records a run waiting for a signal through 65
   completed updates, then a 66th left accepted, against published 2.11.5
   ([checkpoint](rust-server-port-checkpoints/2026-10-29-many-updates.md)).
-  The child summary still stops at 100 children over a run's life; that
-  needs its own fixture.
+- **Descriptions with several open children** (October 29, closed).
+  Published PHP describes a parent by its open waits however many children
+  it holds: the first open child, or an open timer ahead of open children,
+  under any parent-close policy. Native's child summary allowed one waiting
+  child at a time, only the `abandon` parent-close policy, at most 100
+  children over a run's life, and no timer beside a child. Such a parent
+  was described with no wait. The `child-descriptions` fixture records five
+  cases against published 2.11.5
+  ([checkpoint](rust-server-port-checkpoints/2026-10-29-child-descriptions.md)).
+  A child with a cancellation policy other than `abandon`, a retry or
+  timeout policy, or beside an open activity is still described without
+  its wait, pending its own evidence.
 - **Trace context (Core 2.10, published in Server 2.11.1).** Core adds
   nullable `observability_context` columns on runs, commands and tasks.
   Native has no carrier: it accepts and ignores a top-level carrier on
diff --git a/rust/src/runtime/child_summary.rs b/rust/src/runtime/child_summary.rs
index c4bd8999a..4fca09954 100644
--- a/rust/src/runtime/child_summary.rs
+++ b/rust/src/runtime/child_summary.rs
@@ -1,4 +1,5 @@
-//! Sequential child liveness requires original typed identity and retained waits.
+//! Child liveness requires original typed identity and retained waits. A run
+//! may hold any number of open children, each under any parent-close policy.
 use super::{
     Result,
     active_summary::{ActiveSummary, SummaryWait},
@@ -33,13 +34,10 @@ impl ChildSummaryHistory {
             return false;
         };
         if event == "ChildWorkflowScheduled" {
-            if self.calls.len() >= 100
-                || self.calls.contains_key(&sequence)
-                || self
-                    .calls
-                    .values()
-                    .any(|child| child.status == "waiting" || child.id == identity.id)
-                || payload["parent_close_policy"] != "abandon"
+            // Any number of children may be open at once, and the parent-close
+            // policy only decides what happens when the parent closes.
+            if self.calls.contains_key(&sequence)
+                || self.calls.values().any(|child| child.id == identity.id)
                 || payload["cancellation_policy"] != "abandon"
                 || !payload["retry_policy"].is_null()
                 || !payload["timeout_policy"].is_null()
@@ -152,9 +150,9 @@ where
         history: &ChildSummaryHistory,
         summary: &mut ActiveSummary,
     ) -> Result<bool> {
-        let rows = Self::query("SELECT w.*,c.status AS call_status,c.resolved_child_run_id,c.resolved_child_instance_id,c.child_workflow_type,c.metadata AS call_metadata,l.id AS link_id,l.child_workflow_run_id AS link_run,l.child_workflow_instance_id AS link_instance FROM workflow_run_waits w LEFT JOIN workflow_child_calls c ON c.parent_workflow_run_id=w.workflow_run_id AND c.sequence=w.sequence LEFT JOIN workflow_links l ON l.parent_workflow_run_id=w.workflow_run_id AND l.sequence=w.sequence AND l.link_type='child_workflow' WHERE w.workflow_run_id=$1 AND w.kind='child' ORDER BY w.sequence LIMIT 101")
+        let rows = Self::query("SELECT w.*,c.status AS call_status,c.resolved_child_run_id,c.resolved_child_instance_id,c.child_workflow_type,c.metadata AS call_metadata,l.id AS link_id,l.child_workflow_run_id AS link_run,l.child_workflow_instance_id AS link_instance FROM workflow_run_waits w LEFT JOIN workflow_child_calls c ON c.parent_workflow_run_id=w.workflow_run_id AND c.sequence=w.sequence LEFT JOIN workflow_links l ON l.parent_workflow_run_id=w.workflow_run_id AND l.sequence=w.sequence AND l.link_type='child_workflow' WHERE w.workflow_run_id=$1 AND w.kind='child' ORDER BY w.sequence")
             .bind(run_id).fetch_all(&mut **tx).await?;
-        if rows.len() != history.calls.len() || rows.len() > 100 {
+        if rows.len() != history.calls.len() {
             return Ok(false);
         }
         for row in &rows {
@@ -171,7 +169,16 @@ where
         if rows.is_empty() {
             return Ok(true);
         }
-        // Other wait families retain their separately qualified precedence.
+        // An open timer wait describes the run ahead of open children, as
+        // PHP's run description does. Other wait families, and a resolved
+        // child beside a timer, retain their separately qualified precedence.
+        let all_open = rows.iter().all(|row| DB::string(row, "status").is_ok_and(|status| status == "open"));
+        if summary.wait.as_ref().is_some_and(|wait| wait.kind == "timer")
+            && all_open
+            && summary.task_type.as_deref().is_none_or(|kind| kind == "timer")
+        {
+            return Ok(true);
+        }
         if summary
             .wait
             .as_ref()
diff --git a/rust/tests/execution.rs b/rust/tests/execution.rs
index 5f15f7c8b..db2b7a7f8 100644
--- a/rust/tests/execution.rs
+++ b/rust/tests/execution.rs
@@ -352,6 +352,8 @@ mod close_inventory;
 mod start_search_attributes;
 #[path = "execution/worker_error_bodies.rs"]
 mod worker_error_bodies;
+#[path = "execution/child_descriptions.rs"]
+mod child_descriptions;
 
 enum TestDatabase {
     Sqlite(tempfile::TempDir),
diff --git a/rust/tests/execution/child_descriptions.rs b/rust/tests/execution/child_descriptions.rs
new file mode 100644
index 000000000..10cb8e39a
--- /dev/null
+++ b/rust/tests/execution/child_descriptions.rs
@@ -0,0 +1,42 @@
+use super::*;
+
+// Published Server 2.11.5 describes a parent by its open waits however many
+// children it holds: the first open child, or an open timer ahead of open
+// children, under any parent-close policy. The child-descriptions fixture
+// records the same cases.
+
+fn child(policy: Option<&str>) -> Value {
+    let mut command = json!({"type":"start_child_workflow","workflow_type":"echo","arguments":envelope(Payload::Array(vec![]))});
+    if let Some(policy) = policy {
+        command["parent_close_policy"] = json!(policy);
+    }
+    command
+}
+
+#[tokio::test]
+async fn a_parent_is_described_by_its_waits_with_several_children() {
+    let timer = json!({"type":"start_timer","delay_seconds":3600});
+    let child_wait = (json!("child"), json!("Waiting for child workflow echo"));
+    let timer_wait = (json!("timer"), json!("Waiting for timer"));
+    for (id, commands, expected) in [
+        ("one-child", json!([child(None)]), child_wait.clone()),
+        ("two-children", json!([child(None), child(None)]), child_wait.clone()),
+        ("child-then-timer", json!([child(None), timer.clone()]), timer_wait.clone()),
+        ("timer-then-child", json!([timer.clone(), child(None)]), timer_wait.clone()),
+        ("terminating-child", json!([child(Some("terminate"))]), child_wait.clone()),
+    ] {
+        let database = TestDatabase::new().await;
+        let runtime = database.open().await.unwrap();
+        let app = router(runtime.clone());
+        register(&app, "worker", json!(["echo"]), json!([])).await;
+        start(&app, id).await;
+        let task = poll(&app, "worker", "workflow").await;
+        let (status, body) = finish_task(&app, &task, commands).await;
+        assert_eq!(status, StatusCode::OK, "{id}: {body}");
+        let (_, described) = request(&app, "GET", &format!("/api/workflows/{id}"), Value::Null).await;
+        assert_eq!(described["status"], "waiting", "{id}: {described}");
+        assert_eq!((described["wait_kind"].clone(), described["wait_reason"].clone()), expected, "{id}: {described}");
+        runtime.close().await;
+        database.remove().await;
+    }
+}
diff --git a/scripts/conformance/server-parity/child-descriptions-contract.mjs b/scripts/conformance/server-parity/child-descriptions-contract.mjs
new file mode 100644
index 000000000..fb537c566
--- /dev/null
+++ b/scripts/conformance/server-parity/child-descriptions-contract.mjs
@@ -0,0 +1,23 @@
+import assert from 'node:assert/strict';
+
+// Reviewed parent descriptions while children are open
+// (child-descriptions-probe.php), recorded against published Server 2.11.5.
+// The fixture's `expected` holds the whole observation.
+export function checkChildDescriptions(fixture, observation) {
+  const definition = fixture.child_descriptions;
+  const state = observation.child_descriptions;
+  const projection = {scope: 'child_descriptions', cases: Object.keys(definition.cases).length};
+  assert.ok(state && typeof state === 'object', 'actual child descriptions observation');
+  if (observation.mode === 'embedded') {
+    assert.deepStrictEqual(state, {applicable: false, reason: 'embedded_has_no_worker_protocol'},
+      'embedded child descriptions explicitly inapplicable');
+    return projection;
+  }
+  assert.equal(state.applicable, true, 'HTTP targets record child descriptions');
+  for (const [run, expected] of Object.entries(definition.expected)) {
+    assert.deepStrictEqual(state[run], expected, `child descriptions ${run}`);
+  }
+  assert.deepStrictEqual(Object.keys(state).sort(), ['applicable', ...Object.keys(definition.expected)].sort(),
+    'child descriptions cases');
+  return projection;
+}
diff --git a/scripts/conformance/server-parity/child-descriptions-probe.php b/scripts/conformance/server-parity/child-descriptions-probe.php
new file mode 100644
index 000000000..eda1cc58b
--- /dev/null
+++ b/scripts/conformance/server-parity/child-descriptions-probe.php
@@ -0,0 +1,83 @@
+<?php
+
+declare(strict_types=1);
+
+use DurableWorkflow\Client;
+use GuzzleHttp\Client as ChildDescriptionsHttp;
+use GuzzleHttp\HandlerStack;
+
+// A parent run's description while its children are open, over raw worker
+// HTTP on protocol 1.20 in a fresh namespace (published Server
+// WorkflowController::show, Workflow RunWaitView). Each case starts a
+// parent, completes its first workflow task with the case's child and timer
+// commands, and records the completion answer and the parent's description.
+function finishHttpChildDescriptions(Client $admin, array $fixture, string $workflowId, string $url): array
+{
+    $definition = $fixture['child_descriptions'];
+    $namespace = strtolower($workflowId.'-cd');
+    $admin->createNamespace($namespace, 'child descriptions λ', 30);
+    $token = getenv('DW_PARITY_TOKEN') ?: null;
+    $stack = HandlerStack::create();
+    $stack->push(LockPressurePollRetries::middleware(), 'lock_pressure_poll_retry');
+    $http = new ChildDescriptionsHttp(['base_uri' => rtrim($url, '/').'/api/', 'http_errors' => false,
+        'connect_timeout' => 1, 'timeout' => 30, 'handler' => $stack]);
+    $headers = array_filter([
+        'Authorization' => $token === null ? null : 'Bearer '.$token,
+        'Accept' => 'application/json', 'X-Namespace' => $namespace,
+        'X-Durable-Workflow-Control-Plane-Version' => '2', 'X-Durable-Workflow-Protocol-Version' => '1.20',
+    ]);
+    $raw = static function (string $method, string $path, ?array $body = null) use ($http, $headers): array {
+        $response = $http->request($method, $path, ['headers' => $headers,
+            ...($body === null ? [] : ['json' => $body === [] ? (object) [] : $body])]);
+
+        return ['status' => $response->getStatusCode(),
+            'response' => json_decode((string) $response->getBody(), true, flags: JSON_THROW_ON_ERROR)];
+    };
+    $empty = ['codec' => 'avro', 'blob' => $definition['empty_blob']];
+    $state = ['applicable' => true];
+    foreach ($definition['cases'] as $case => $commands) {
+        $id = $workflowId.'-cd-'.$case;
+        $queue = $id.'-queue';
+        $worker = $id.'-worker';
+        $registered = $raw('POST', 'worker/register', ['worker_id' => $worker, 'task_queue' => $queue, 'runtime' => 'php',
+            'sdk_version' => 'raw-http', 'supported_workflow_types' => [$definition['workflow_type'], $definition['child_type']],
+            'supported_activity_types' => [],
+            'capability_manifest' => array_fill_keys(['local_activities', 'worker_sessions', 'sticky_execution'],
+                ['supported' => false, 'minimum_protocol_version' => '1.18', 'reason' => 'raw_http'])]);
+        $started = $raw('POST', 'workflows', ['workflow_id' => $id, 'workflow_type' => $definition['workflow_type'],
+            'task_queue' => $queue, 'input' => $empty]);
+        if ($registered['status'] !== 201 || $started['status'] !== 201) {
+            throw new RuntimeException('Child descriptions setup: '.json_encode([$registered, $started]));
+        }
+        $task = $raw('POST', 'worker/workflow-tasks/poll', ['worker_id' => $worker, 'task_queue' => $queue,
+            'timeout_seconds' => 5])['response']['task'] ?? null;
+        if (! is_array($task)) {
+            throw new RuntimeException('Child descriptions: no workflow task for '.$case);
+        }
+        $completed = $raw('POST', 'worker/workflow-tasks/'.$task['task_id'].'/complete', ['lease_owner' => $task['lease_owner'],
+            'workflow_task_attempt' => $task['workflow_task_attempt'], 'commands' => $commands]);
+        $described = $raw('GET', 'workflows/'.rawurlencode($id))['response'];
+        $state[$case] = [
+            'completed' => ['status' => $completed['status'], 'reason' => $completed['response']['reason'] ?? null,
+                'run_status' => $completed['response']['run_status'] ?? null],
+            'described' => array_intersect_key($described, array_flip($definition['described_fields'])),
+        ];
+        // End the children and then the parent, so their never-polled tasks
+        // do not stay for the maintenance passes of later fixtures.
+        $events = $raw('GET', 'workflows/'.rawurlencode($id).'/runs/'.$started['response']['run_id'].'/history')['response']['events'] ?? [];
+        $ended = [];
+        foreach ($events as $event) {
+            if ($event['event_type'] === 'ChildWorkflowScheduled' && is_string($event['payload']['child_workflow_instance_id'] ?? null)) {
+                $ended[] = $event['payload']['child_workflow_instance_id'];
+            }
+        }
+        foreach ([...$ended, $id] as $instance) {
+            $terminated = $raw('POST', 'workflows/'.rawurlencode($instance).'/terminate', ['reason' => 'child descriptions recorded']);
+            if (! in_array($terminated['status'], [200, 202], true)) {
+                throw new RuntimeException('Child descriptions cleanup: '.json_encode($terminated));
+            }
+        }
+    }
+
+    return $state;
+}
diff --git a/scripts/conformance/server-parity/contract.mjs b/scripts/conformance/server-parity/contract.mjs
index ac81f43c7..c43cb3587 100644
--- a/scripts/conformance/server-parity/contract.mjs
+++ b/scripts/conformance/server-parity/contract.mjs
@@ -18,6 +18,7 @@ import {checkContinueTransfers} from './continue-transfers-contract.mjs';
 import {checkLargeCommandBatches} from './large-command-batches-contract.mjs';
 import {checkManyUpdates} from './many-updates-contract.mjs';
 import {checkWorkerErrorBodies} from './worker-error-bodies-contract.mjs';
+import {checkChildDescriptions} from './child-descriptions-contract.mjs';
 import {checkStartSearchAttributes} from './start-search-attributes-contract.mjs';
 import {checkQueryArgumentRouting} from './query-arguments-contract.mjs';
 import {checkQueryContractArguments} from './query-contract-arguments-contract.mjs';
@@ -181,6 +182,7 @@ export function checkObservation(fixture, observation, workflowId, artifacts) {
   const largeCommandBatches = fixture.large_command_batches ? checkLargeCommandBatches(fixture, observation) : null;
   const manyUpdates = fixture.many_updates ? checkManyUpdates(fixture, observation) : null;
   const workerErrorBodies = fixture.worker_error_bodies ? checkWorkerErrorBodies(fixture, observation) : null;
+  const childDescriptions = fixture.child_descriptions ? checkChildDescriptions(fixture, observation) : null;
   const startSearchAttributes = fixture.start_search_attributes ? checkStartSearchAttributes(fixture, observation) : null;
   const queryArguments = fixture.query_argument_routing ? checkQueryArgumentRouting(fixture, observation) : null;
   const queryContractArguments = fixture.query_contract_arguments ? checkQueryContractArguments(fixture, observation) : null;
@@ -762,6 +764,7 @@ export function checkObservation(fixture, observation, workflowId, artifacts) {
     ...(largeCommandBatches ? {large_command_batches: largeCommandBatches} : {}),
     ...(manyUpdates ? {many_updates: manyUpdates} : {}),
     ...(workerErrorBodies ? {worker_error_bodies: workerErrorBodies} : {}),
+    ...(childDescriptions ? {child_descriptions: childDescriptions} : {}),
     ...(startSearchAttributes ? {start_search_attributes: startSearchAttributes} : {}),
     ...(queryArguments ? {query_argument_routing: queryArguments} : {}),
     ...(queryContractArguments ? {query_contract_arguments: queryContractArguments} : {}),
diff --git a/scripts/conformance/server-parity/probe.php b/scripts/conformance/server-parity/probe.php
index 0790284be..1d2df32a6 100644
--- a/scripts/conformance/server-parity/probe.php
+++ b/scripts/conformance/server-parity/probe.php
@@ -436,6 +436,7 @@ function httpObservation(array $fixture, string $workflowId, string $namespace,
     $largeCommandBatches = isset($fixture['large_command_batches']) ? finishHttpLargeCommandBatches($client, $fixture, $workflowId, $url) : null;
     $manyUpdates = isset($fixture['many_updates']) ? finishHttpManyUpdates($client, $fixture, $workflowId, $url) : null;
     $workerErrorBodies = isset($fixture['worker_error_bodies']) ? finishHttpWorkerErrorBodies($client, $fixture, $workflowId, $url) : null;
+    $childDescriptions = isset($fixture['child_descriptions']) ? finishHttpChildDescriptions($client, $fixture, $workflowId, $url) : null;
     $startSearchAttributes = isset($fixture['start_search_attributes']) ? finishHttpStartSearchAttributes($client, $fixture, $workflowId, $url) : null;
     $queryArgumentRouting = isset($fixture['query_argument_routing']) ? finishHttpQueryArgumentRouting($client, $fixture, $workflowId, $url) : null;
     $queryContractArguments = isset($fixture['query_contract_arguments']) ? finishHttpQueryContractArguments($client, $fixture, $workflowId, $url) : null;
@@ -570,6 +571,7 @@ function httpObservation(array $fixture, string $workflowId, string $namespace,
         'large_command_batches' => $largeCommandBatches,
         'many_updates' => $manyUpdates,
         'worker_error_bodies' => $workerErrorBodies,
+        'child_descriptions' => $childDescriptions,
         'start_search_attributes' => $startSearchAttributes,
         'query_argument_routing' => $queryArgumentRouting,
         'query_contract_arguments' => $queryContractArguments,
@@ -907,6 +909,7 @@ function embeddedObservation(array $fixture, string $workflowId, string $namespa
     require __DIR__.'/large-command-batches-probe.php';
     require __DIR__.'/many-updates-probe.php';
     require __DIR__.'/worker-error-bodies-probe.php';
+    require __DIR__.'/child-descriptions-probe.php';
     require __DIR__.'/start-search-attributes-probe.php';
     require __DIR__.'/query-arguments-probe.php';
     require __DIR__.'/query-contract-arguments-probe.php';
@@ -1108,6 +1111,9 @@ function embeddedObservation(array $fixture, string $workflowId, string $namespa
     if ($mode === 'embedded' && isset($fixture['worker_error_bodies'])) {
         $observation['worker_error_bodies'] = ['applicable' => false, 'reason' => 'embedded_has_no_worker_protocol'];
     }
+    if ($mode === 'embedded' && isset($fixture['child_descriptions'])) {
+        $observation['child_descriptions'] = ['applicable' => false, 'reason' => 'embedded_has_no_worker_protocol'];
+    }
     if ($mode === 'embedded' && isset($fixture['start_search_attributes'])) {
         $observation['start_search_attributes'] = ['applicable' => false, 'reason' => 'embedded_has_no_http_search_attribute_registry'];
     }
diff --git a/tests/Fixtures/ServerParity/child-descriptions.json b/tests/Fixtures/ServerParity/child-descriptions.json
new file mode 100644
index 000000000..465af5c15
--- /dev/null
+++ b/tests/Fixtures/ServerParity/child-descriptions.json
@@ -0,0 +1,200 @@
+{
+  "schema": "durable-workflow.server-parity-fixture/v1",
+  "id": "child-descriptions",
+  "review_state": "reviewed",
+  "contract": "A parent run's description while its children are open (published Server 2.11.5 WorkflowController::show with Workflow 2.15.1 RunWaitView), over raw worker HTTP on protocol 1.20 in a fresh namespace. Each case completes the parent's first workflow task with child and timer commands and records the description. A parent with two open children is described as waiting for a child; with an open child and an open timer, in either order, as waiting for the timer; and a child under parent_close_policy terminate is described like any other. Embedded applications have no worker protocol.",
+  "workflow_type": "parity.v1.echo",
+  "input": {
+    "message": "continue transfers λ",
+    "count": 9007199254740993,
+    "optional": null
+  },
+  "typed_value": {
+    "type": "map",
+    "value": {
+      "message": {
+        "type": "string",
+        "value": "continue transfers λ"
+      },
+      "count": {
+        "type": "int64",
+        "value": "9007199254740993"
+      },
+      "optional": {
+        "type": "null",
+        "value": null
+      }
+    }
+  },
+  "activity": false,
+  "expected_events": [
+    "StartAccepted",
+    "WorkflowStarted",
+    "WorkflowCompleted"
+  ],
+  "child_descriptions": {
+    "workflow_type": "parity.v1.child_descriptions",
+    "child_type": "parity.v1.child_descriptions_child",
+    "empty_blob": "wwHioz3/VYAiNwwA",
+    "described_fields": [
+      "status",
+      "status_bucket",
+      "is_terminal",
+      "resume_step_sequence",
+      "recovery_kind",
+      "wait_kind",
+      "wait_reason"
+    ],
+    "cases": {
+      "one_child": [
+        {
+          "type": "start_child_workflow",
+          "workflow_type": "parity.v1.child_descriptions_child",
+          "arguments": {
+            "codec": "avro",
+            "blob": "wwHioz3/VYAiNwwA"
+          }
+        }
+      ],
+      "two_children": [
+        {
+          "type": "start_child_workflow",
+          "workflow_type": "parity.v1.child_descriptions_child",
+          "arguments": {
+            "codec": "avro",
+            "blob": "wwHioz3/VYAiNwwA"
+          }
+        },
+        {
+          "type": "start_child_workflow",
+          "workflow_type": "parity.v1.child_descriptions_child",
+          "arguments": {
+            "codec": "avro",
+            "blob": "wwHioz3/VYAiNwwA"
+          }
+        }
+      ],
+      "child_then_timer": [
+        {
+          "type": "start_child_workflow",
+          "workflow_type": "parity.v1.child_descriptions_child",
+          "arguments": {
+            "codec": "avro",
+            "blob": "wwHioz3/VYAiNwwA"
+          }
+        },
+        {
+          "type": "start_timer",
+          "delay_seconds": 3600
+        }
+      ],
+      "timer_then_child": [
+        {
+          "type": "start_timer",
+          "delay_seconds": 3600
+        },
+        {
+          "type": "start_child_workflow",
+          "workflow_type": "parity.v1.child_descriptions_child",
+          "arguments": {
+            "codec": "avro",
+            "blob": "wwHioz3/VYAiNwwA"
+          }
+        }
+      ],
+      "terminating_child": [
+        {
+          "type": "start_child_workflow",
+          "workflow_type": "parity.v1.child_descriptions_child",
+          "arguments": {
+            "codec": "avro",
+            "blob": "wwHioz3/VYAiNwwA"
+          },
+          "parent_close_policy": "terminate"
+        }
+      ]
+    },
+    "expected": {
+      "one_child": {
+        "completed": {
+          "status": 200,
+          "reason": null,
+          "run_status": "waiting"
+        },
+        "described": {
+          "status": "waiting",
+          "status_bucket": "running",
+          "is_terminal": false,
+          "resume_step_sequence": null,
+          "recovery_kind": null,
+          "wait_kind": "child",
+          "wait_reason": "Waiting for child workflow parity.v1.child_descriptions_child"
+        }
+      },
+      "two_children": {
+        "completed": {
+          "status": 200,
+          "reason": null,
+          "run_status": "waiting"
+        },
+        "described": {
+          "status": "waiting",
+          "status_bucket": "running",
+          "is_terminal": false,
+          "resume_step_sequence": null,
+          "recovery_kind": null,
+          "wait_kind": "child",
+          "wait_reason": "Waiting for child workflow parity.v1.child_descriptions_child"
+        }
+      },
+      "child_then_timer": {
+        "completed": {
+          "status": 200,
+          "reason": null,
+          "run_status": "waiting"
+        },
+        "described": {
+          "status": "waiting",
+          "status_bucket": "running",
+          "is_terminal": false,
+          "resume_step_sequence": null,
+          "recovery_kind": null,
+          "wait_kind": "timer",
+          "wait_reason": "Waiting for timer"
+        }
+      },
+      "timer_then_child": {
+        "completed": {
+          "status": 200,
+          "reason": null,
+          "run_status": "waiting"
+        },
+        "described": {
+          "status": "waiting",
+          "status_bucket": "running",
+          "is_terminal": false,
+          "resume_step_sequence": null,
+          "recovery_kind": null,
+          "wait_kind": "timer",
+          "wait_reason": "Waiting for timer"
+        }
+      },
+      "terminating_child": {
+        "completed": {
+          "status": 200,
+          "reason": null,
+          "run_status": "waiting"
+        },
+        "described": {
+          "status": "waiting",
+          "status_bucket": "running",
+          "is_terminal": false,
+          "resume_step_sequence": null,
+          "recovery_kind": null,
+          "wait_kind": "child",
+          "wait_reason": "Waiting for child workflow parity.v1.child_descriptions_child"
+        }
+      }
+    }
+  }
+}
diff --git a/tests/Unit/ServerParityChildDescriptionsContractTest.mjs b/tests/Unit/ServerParityChildDescriptionsContractTest.mjs
new file mode 100644
index 000000000..56651b0cd
--- /dev/null
+++ b/tests/Unit/ServerParityChildDescriptionsContractTest.mjs
@@ -0,0 +1,33 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import {readFileSync} from 'node:fs';
+import {checkChildDescriptions} from '../../scripts/conformance/server-parity/child-descriptions-contract.mjs';
+
+const fixture = JSON.parse(readFileSync(new URL('../Fixtures/ServerParity/child-descriptions.json', import.meta.url), 'utf8'));
+const expected = fixture.child_descriptions.expected;
+const observation = () => structuredClone({mode: 'http', child_descriptions: {applicable: true, ...expected}});
+const cases = Object.keys(fixture.child_descriptions.cases).length;
+
+test('the published answers pass', () => {
+  assert.deepStrictEqual(checkChildDescriptions(fixture, observation()), {scope: 'child_descriptions', cases});
+});
+
+test('embedded applications have no worker protocol', () => {
+  assert.deepStrictEqual(checkChildDescriptions(fixture,
+    {mode: 'embedded', child_descriptions: {applicable: false, reason: 'embedded_has_no_worker_protocol'}}),
+  {scope: 'child_descriptions', cases});
+});
+
+test('children and timers are described by the published precedence', () => {
+  assert.deepStrictEqual(Object.fromEntries(Object.entries(expected).map(([name, run]) => [name, run.described.wait_kind])),
+    {one_child: 'child', two_children: 'child', child_then_timer: 'timer', timer_then_child: 'timer', terminating_child: 'child'});
+});
+
+for (const [name, mutate] of [
+  ['two children described without a wait', state => { state.two_children.described.wait_kind = null; }],
+  ['a child ahead of an open timer', state => { state.child_then_timer.described.wait_kind = 'child'; }],
+  ['an unexpected case', state => { state.extra = {}; }],
+]) test(`the contract rejects ${name}`, () => {
+  const raw = observation(); mutate(raw.child_descriptions);
+  assert.throws(() => checkChildDescriptions(fixture, raw));
+});