diff --git a/apps/server/src/pullRequest/PullRequestService.test.ts b/apps/server/src/pullRequest/PullRequestService.test.ts
index a438ac780f43..a3cb8ae76d48 100644
--- a/apps/server/src/pullRequest/PullRequestService.test.ts
+++ b/apps/server/src/pullRequest/PullRequestService.test.ts
@@ -2748,6 +2748,34 @@ it.effect("deduplicates routed PR reports without dropping draft changes", () =>
   }),
 );
 
+it.effect("preserves check observation time on cache hits and advances it on refresh", () =>
+  Effect.gen(function* () {
+    let reads = 0;
+    const reference = { projectId: "p1" as ProjectId, repository: "acme/web", number: 1 };
+    const service = yield* makeService({
+      projects: [project({ id: "p1", title: "web", workspaceRoot: "/a", repository: "acme/web" })],
+      providers: [
+        fakeProvider(SourceControlProviderKind.make("github"), {
+          getChangeRequestChecks: () =>
+            Effect.sync(() => {
+              reads += 1;
+              return { state: "open" as const, checks: [] };
+            }),
+        }),
+      ],
+    });
+    yield* TestClock.setTime(1_000);
+    const first = yield* service.checks(reference);
+    expect(first).toMatchObject({ observedAt: 1_000 });
+    yield* TestClock.adjust("1 second");
+    expect(yield* service.checks(reference)).toEqual(first);
+    expect(reads).toBe(1);
+    yield* TestClock.adjust("15 seconds");
+    expect(yield* service.checks(reference)).toMatchObject({ observedAt: 17_000 });
+    expect(reads).toBe(2);
+  }),
+);
+
 it.effect("reuses an observed merged state for strict settlement reads", () =>
   Effect.gen(function* () {
     const reference = { projectId: "p1" as ProjectId, repository: "acme/web", number: 1 };
diff --git a/apps/server/src/pullRequest/PullRequestService.ts b/apps/server/src/pullRequest/PullRequestService.ts
index 3c6c9b333fbf..bc763834f7f6 100644
--- a/apps/server/src/pullRequest/PullRequestService.ts
+++ b/apps/server/src/pullRequest/PullRequestService.ts
@@ -2790,7 +2790,11 @@ export const make = Effect.gen(function* () {
                   host: project.host,
                   number: input.number,
                 })
-                .pipe(Effect.mapError(toPullRequestError("checks"))),
+                .pipe(
+                  Effect.mapError(toPullRequestError("checks")),
+                  observeRead,
+                  Effect.map(({ value, observedAt }) => ({ ...value, observedAt })),
+                ),
         ),
       );
     },
diff --git a/apps/web/src/components/chat/ThreadDetailsPrRow.tsx b/apps/web/src/components/chat/ThreadDetailsPrRow.tsx
index c6741fa035e4..85c65005b9d8 100644
--- a/apps/web/src/components/chat/ThreadDetailsPrRow.tsx
+++ b/apps/web/src/components/chat/ThreadDetailsPrRow.tsx
@@ -32,6 +32,7 @@ import {
   buildFixFindingsHandoff,
   buildResolveConflictsPrompt,
   classifyPullRequestChecks,
+  resolvePullRequestDetailChecks,
   describePullRequestChecks,
   isPullRequestConflicting,
   resolvePullRequestMergeMethod,
@@ -135,12 +136,7 @@ export function ThreadDetailsPrRow({
   const checksSettledEmpty = useEnvironmentQuerySelector(checksAtom, isSettledWithoutChecks);
   const checksQuery = useEnvironmentQueryRefresh(checksAtom);
   const checksAreNewer = useEnvironmentQueryIsNewer(checksAtom, detailAtom);
-  const detail =
-    detailData === null
-      ? null
-      : checksData !== null && checksAreNewer
-        ? { ...detailData, ...checksData }
-        : detailData;
+  const detail = resolvePullRequestDetailChecks(detailData, checksData, checksAreNewer);
   const open = reference !== null && (detail?.state ?? pr?.state) === "open";
   const refreshKey = `${environmentId}:${project?.id}:${reference?.host}:${reference?.repository}:${number}`;
   useLiveRefresh(
diff --git a/apps/web/src/components/pullRequest/pullRequestDetail.logic.test.ts b/apps/web/src/components/pullRequest/pullRequestDetail.logic.test.ts
index ad7e99ecf87e..292d40bfe400 100644
--- a/apps/web/src/components/pullRequest/pullRequestDetail.logic.test.ts
+++ b/apps/web/src/components/pullRequest/pullRequestDetail.logic.test.ts
@@ -46,6 +46,7 @@ import {
   checkoutFailureDescription,
   readPullRequestDetailSnapshot,
   resolveDisplayedPullRequestDetail,
+  resolvePullRequestDetailChecks,
   resolvePullRequestReferenceHost,
   resolvePullRequestPrimaryControl,
   allowsSinglePullRequestMerge,
@@ -1245,6 +1246,59 @@ describe("cached pull request detail", () => {
       ...overrides,
     }) as PullRequestDetail;
 
+  it("uses fresh checks for detail counts without replacing other PR fields", () => {
+    const pending = (name: string): PullRequestCheck => ({
+      name,
+      status: "pending",
+      url: null,
+      description: null,
+    });
+    const original = detail({ checks: [pending("build"), pending("test")] });
+    const checks = [pending("build"), { ...pending("test"), status: "success" as const }];
+    expect(resolvePullRequestDetailChecks(original, { state: "closed", checks }, true)).toEqual({
+      ...original,
+      state: "closed",
+      checks,
+    });
+    expect(resolvePullRequestDetailChecks(original, { state: "closed", checks }, false)).toBe(
+      original,
+    );
+    expect(resolvePullRequestDetailChecks(original, null, true)).toBe(original);
+    expect(resolvePullRequestDetailChecks(null, { state: "closed", checks }, true)).toBeNull();
+  });
+
+  it("keeps newer checks when an older cached detail arrives later", () => {
+    const pending: PullRequestCheck = {
+      name: "build",
+      status: "pending",
+      url: null,
+      description: null,
+    };
+    const cached = detail({ observedAt: 1_000, checks: [pending] });
+    const checks = {
+      state: "open" as const,
+      checks: [{ ...pending, status: "success" as const }],
+      observedAt: 2_000,
+    };
+    const resolved = resolvePullRequestDetailChecks(cached, checks, false);
+    expect(resolved?.checks).toEqual(checks.checks);
+    expect(resolved?.observedAt).toBe(1_000);
+    expect(
+      resolvePullRequestDetailChecks(cached, { state: checks.state, checks: checks.checks }, true)
+        ?.checks,
+    ).toEqual(checks.checks);
+    const refreshed = detail({ observedAt: 3_000, checks: [pending] });
+    expect(resolvePullRequestDetailChecks(refreshed, checks, true)).toBe(refreshed);
+  });
+
+  it("keeps merged details settled while applying newer checks", () => {
+    const merged = detail({ state: "merged", observedAt: 1_000 });
+    const checks = [{ name: "build", status: "success" as const, url: null, description: null }];
+    expect(
+      resolvePullRequestDetailChecks(merged, { state: "open", observedAt: 2_000, checks }, true),
+    ).toEqual({ ...merged, checks });
+  });
+
   const makeStorage = () => {
     const held = new Map<string, string>();
     return {
diff --git a/apps/web/src/components/pullRequest/pullRequestDetail.logic.ts b/apps/web/src/components/pullRequest/pullRequestDetail.logic.ts
index b4d7a7052163..217a36ee54c7 100644
--- a/apps/web/src/components/pullRequest/pullRequestDetail.logic.ts
+++ b/apps/web/src/components/pullRequest/pullRequestDetail.logic.ts
@@ -10,6 +10,7 @@ import {
   type PullRequestActor,
   type PullRequestBaseComparison,
   type PullRequestCheck,
+  type PullRequestChecks,
   type PullRequestChecksState as ContractPullRequestChecksState,
   type PullRequestComment,
   type PullRequestCommit,
@@ -1419,3 +1420,22 @@ export function resolveDisplayedPullRequestDetail(input: {
     return null;
   }
 }
+
+export function resolvePullRequestDetailChecks(
+  detail: PullRequestDetail | null,
+  checks: PullRequestChecks | null,
+  checksAreNewer: boolean,
+): PullRequestDetail | null {
+  if (detail === null || checks === null) return detail;
+  const newer =
+    detail.observedAt !== undefined && checks.observedAt !== undefined
+      ? checks.observedAt >= detail.observedAt
+      : checksAreNewer;
+  return newer
+    ? {
+        ...detail,
+        state: detail.state === "merged" ? "merged" : checks.state,
+        checks: checks.checks,
+      }
+    : detail;
+}
diff --git a/apps/web/src/components/pullRequest/usePullRequestDetail.ts b/apps/web/src/components/pullRequest/usePullRequestDetail.ts
index a3228f6b64fa..2ef76be9b159 100644
--- a/apps/web/src/components/pullRequest/usePullRequestDetail.ts
+++ b/apps/web/src/components/pullRequest/usePullRequestDetail.ts
@@ -7,6 +7,8 @@ import {
 } from "@t3tools/contracts";
 import { useEffect, useEffectEvent, useState } from "react";
 
+import { usePullRequestChecksRefresh } from "~/hooks/usePullRequestChecksRefresh";
+import { useServerConfigs } from "~/state/entities";
 import { useEnvironmentQuery } from "~/state/query";
 import { useEnvironmentScope } from "~/state/session";
 import {
@@ -18,6 +20,7 @@ import {
 import {
   readPullRequestDetailSnapshot,
   resolveDisplayedPullRequestDetail,
+  resolvePullRequestDetailChecks,
   writePullRequestDetailSnapshot,
 } from "./pullRequestDetail.logic";
 import { pullRequestChecksState } from "./pullRequestPresentation";
@@ -42,11 +45,35 @@ export function usePullRequestDetail(
   const scopeKey = `${environmentId}:${pullRequestRefKey(reference)}`;
   const canWriteSourceControl = useEnvironmentScope(environmentId, AuthSourceControlWriteScope);
   const detailQuery = useEnvironmentQuery(
-    pullRequestEnvironment.detail({ environmentId, input: reference }),
+    pullRequestEnvironment.detail({ environmentId, input: { ...reference, allowStale: false } }),
   );
   const activityQuery = useEnvironmentQuery(
     pullRequestEnvironment.activity({ environmentId, input: reference }),
   );
+  const serverConfigs = useServerConfigs();
+  const supportsChecks =
+    serverConfigs.get(environmentId)?.environment.capabilities.pullRequestChecks === true;
+  const checksQuery = useEnvironmentQuery(
+    supportsChecks && detailQuery.data !== null
+      ? pullRequestEnvironment.checks({ environmentId, input: reference })
+      : null,
+  );
+  const liveDetail = resolvePullRequestDetailChecks(
+    detailQuery.data,
+    checksQuery.data,
+    checksQuery.dataUpdatedAt >= detailQuery.dataUpdatedAt,
+  );
+  usePullRequestChecksRefresh({
+    refresh: () => {
+      if (!checksQuery.isPending && !detailQuery.isPending) checksQuery.refresh();
+    },
+    enabled:
+      liveDetail?.state === "open" &&
+      supportsChecks &&
+      !(checksQuery.isSuccess && checksQuery.data === null),
+    key: `workspace-pr-checks:${environmentId}:${reference.projectId}:${reference.host}:${reference.repository}:${reference.number}`,
+    checks: liveDetail?.checks ?? [],
+  });
   const [cachedDetail, setCachedDetail] = useState(() =>
     readPullRequestDetailSnapshot(
       typeof window === "undefined" ? undefined : window.localStorage,
@@ -79,16 +106,16 @@ export function usePullRequestDetail(
   useEffect(() => {
     if (detailQuery.data !== null) saveDetailSnapshot(detailQuery.data);
   }, [detailQuery.data]);
-  const detailSummary = pullRequestDetailSummary(detailQuery.data);
+  const detailSummary = pullRequestDetailSummary(liveDetail);
   const observedSummary = useSharedPullRequestSummary(
     environmentId,
     reference,
     detailSummary,
-    detailQuery.dataUpdatedAt,
+    Math.max(detailQuery.dataUpdatedAt, checksQuery.dataUpdatedAt),
   );
   const activity = activityQuery.data;
   const resolvedCoreDetail = resolveDisplayedPullRequestDetail({
-    live: detailQuery.data,
+    live: liveDetail,
     cached: cachedDetail,
     reference,
   });
diff --git a/packages/client-runtime/src/state/pullRequests.test.ts b/packages/client-runtime/src/state/pullRequests.test.ts
index a3ca6dc62a15..74493ff95fbc 100644
--- a/packages/client-runtime/src/state/pullRequests.test.ts
+++ b/packages/client-runtime/src/state/pullRequests.test.ts
@@ -1277,6 +1277,35 @@ it.effect("shares close, reopen, and merge with an untouched client's mounted PR
   ),
 );
 
+it.effect("shares checks reads across reference property order", () =>
+  Effect.scoped(
+    Effect.gen(function* () {
+      let reads = 0;
+      const client = {
+        [WS_METHODS.pullRequestsSubscribeRefreshes]: () => Stream.never,
+        [WS_METHODS.pullRequestsChecks]: () =>
+          Effect.sync(() => {
+            reads += 1;
+            return { state: "open", checks: [], observedAt: 1_000 };
+          }),
+      } as unknown as WsRpcProtocolClient;
+      const { atoms, registry } = yield* makeTestRuntime(client);
+      const projectId = ProjectId.make("project-1");
+      const row = atoms.checks({
+        environmentId: TARGET.environmentId,
+        input: { host: "github.com", repository: "acme/web", number: 1, projectId },
+      });
+      const panel = atoms.checks({
+        environmentId: TARGET.environmentId,
+        input: { projectId, host: "github.com", repository: "acme/web", number: 1 },
+      });
+      yield* AtomRegistry.getResult(registry, row);
+      yield* AtomRegistry.getResult(registry, panel);
+      expect(reads).toBe(1);
+    }),
+  ),
+);
+
 it.effect("keeps live detail reads separate from reads that allow stale data", () =>
   Effect.scoped(
     Effect.gen(function* () {
diff --git a/packages/client-runtime/src/state/pullRequests.ts b/packages/client-runtime/src/state/pullRequests.ts
index 757037734479..fa5385c09fad 100644
--- a/packages/client-runtime/src/state/pullRequests.ts
+++ b/packages/client-runtime/src/state/pullRequests.ts
@@ -55,6 +55,26 @@ export class EnvironmentHttpConnectionNotReadyError extends Data.TaggedError(
 
 const LINKED_PULL_REQUEST_IDLE_TTL_MS = 5_000;
 
+function normalizePullRequestQuery<A>(
+  query: (target: { readonly environmentId: EnvironmentId; readonly input: PullRequestRef }) => A,
+) {
+  return ({
+    environmentId,
+    input: { projectId, host, repository, number, allowStale, expectedAccountId },
+  }: Parameters<typeof query>[0]) =>
+    query({
+      environmentId,
+      input: {
+        projectId,
+        ...(host === undefined ? {} : { host }),
+        repository,
+        number,
+        ...(allowStale === undefined ? {} : { allowStale }),
+        ...(expectedAccountId === undefined ? {} : { expectedAccountId }),
+      },
+    });
+}
+
 function writableQueryFamily<A, E>(
   family: (target: {
     readonly environmentId: EnvironmentId;
@@ -77,22 +97,7 @@ function writableQueryFamily<A, E>(
       (refresh) => refresh(source),
     ).pipe(Atom.setIdleTTL(5 * 60_000)),
   );
-  return ({
-    environmentId,
-    input: { projectId, host, repository, number, allowStale },
-  }: Parameters<typeof family>[0]) =>
-    writable(
-      family({
-        environmentId,
-        input: {
-          projectId,
-          ...(host === undefined ? {} : { host }),
-          repository,
-          number,
-          ...(allowStale === undefined ? {} : { allowStale }),
-        },
-      }),
-    );
+  return normalizePullRequestQuery((target) => writable(family(target)));
 }
 
 /** Restart pre-mutation reads before patching so they cannot restore stale values. */
@@ -319,14 +324,16 @@ export function createPullRequestEnvironmentAtoms<R, E>(
     }),
     detail,
     preview,
-    checks: createEnvironmentRpcQueryAtomFamily(runtime, {
-      label: "environment-data:pull-requests:checks",
-      persistence: persistQuery(Schema.NullOr(PullRequestChecks)),
-      tag: WS_METHODS.pullRequestsChecks,
-      execute: (input) => routedRequest(WS_METHODS.pullRequestsChecks, input),
-      staleTimeMs: 45_000,
-      refreshTrigger: ({ environmentId }) => refreshes({ environmentId, input: {} }),
-    }),
+    checks: normalizePullRequestQuery(
+      createEnvironmentRpcQueryAtomFamily(runtime, {
+        label: "environment-data:pull-requests:checks",
+        persistence: persistQuery(Schema.NullOr(PullRequestChecks)),
+        tag: WS_METHODS.pullRequestsChecks,
+        execute: (input) => routedRequest(WS_METHODS.pullRequestsChecks, input),
+        staleTimeMs: 45_000,
+        refreshTrigger: ({ environmentId }) => refreshes({ environmentId, input: {} }),
+      }),
+    ),
     activity,
     threadComments: createEnvironmentRpcCommand(runtime, {
       label: "environment-data:pull-requests:thread-comments",
diff --git a/packages/contracts/src/pullRequest.ts b/packages/contracts/src/pullRequest.ts
index a68f5394b0dd..5f9bc23048dd 100644
--- a/packages/contracts/src/pullRequest.ts
+++ b/packages/contracts/src/pullRequest.ts
@@ -589,6 +589,7 @@ export const PullRequestDetail = Schema.Struct({
 export type PullRequestDetail = typeof PullRequestDetail.Type;
 
 export const PullRequestChecks = Schema.Struct({
+  observedAt: Schema.optional(Schema.Finite),
   state: PullRequestState,
   checks: Schema.Array(PullRequestCheck),
 });
diff --git a/packages/source-control-core/src/server/PullRequestProvider.ts b/packages/source-control-core/src/server/PullRequestProvider.ts
index 3bb7a757f773..daa166e654e2 100644
--- a/packages/source-control-core/src/server/PullRequestProvider.ts
+++ b/packages/source-control-core/src/server/PullRequestProvider.ts
@@ -342,7 +342,7 @@ export interface PullRequestProviderApi {
 
   readonly getChangeRequestChecks?: (
     input: ProviderRepositoryRef & { readonly number: number },
-  ) => Effect.Effect<PullRequestChecks, PullRequestProviderError>;
+  ) => Effect.Effect<Pick<PullRequestChecks, "state" | "checks">, PullRequestProviderError>;
 
   readonly getChangeRequest: (
     input: ProviderRepositoryRef & { readonly number: number },