diff --git a/extensions/openrouter/index.ts b/extensions/openrouter/index.ts
index 7c56d8f19ddb..84c5aa168002 100644
--- a/extensions/openrouter/index.ts
+++ b/extensions/openrouter/index.ts
@@ -162,7 +162,8 @@ function resolveFusionExtraBody(
   ];
   let effective: Record<string, unknown> | undefined;
   for (const source of sources) {
-    const raw = source && Object.hasOwn(source, "extra_body") ? source.extra_body : source?.extraBody;
+    const raw =
+      source && Object.hasOwn(source, "extra_body") ? source.extra_body : source?.extraBody;
     const candidate = readRecord(raw);
     if (candidate) {
       effective = candidate;
diff --git a/extensions/openrouter/provider-routing.ts b/extensions/openrouter/provider-routing.ts
index 5871b45546bf..babc30ebf4ac 100644
--- a/extensions/openrouter/provider-routing.ts
+++ b/extensions/openrouter/provider-routing.ts
@@ -73,6 +73,7 @@ function resolveOpenRouterProviderConfigParams(
   for (const [, config] of prioritizedProviders) {
     const params = readRecord(config.params);
     if (params) {
+      // SAFETY: both inputs are sanitized plain records, so the recursive merge remains a record.
       matchedParams = mergeDeep(matchedParams ?? {}, params) as Record<string, unknown>;
     }
   }
diff --git a/src/auto-reply/reply/memory-flush.test.ts b/src/auto-reply/reply/memory-flush.test.ts
index dbce6169cb85..8f57bde36d95 100644
--- a/src/auto-reply/reply/memory-flush.test.ts
+++ b/src/auto-reply/reply/memory-flush.test.ts
@@ -76,14 +76,13 @@ describe("Responses server compaction host/transport parity", () => {
         defaults: {
           params: { responsesCompactThreshold: 120_000 },
         },
-        entries: [
-          {
-            id: "audit",
+        entries: {
+          audit: {
             models: {
               [modelRef]: { params: { responsesCompactThreshold: 175_000 } },
             },
           },
-        ],
+        },
       },
     };