diff --git a/server/src/__tests__/adapter-routes.test.ts b/server/src/__tests__/adapter-routes.test.ts
index e1a730d3ec..eede2af23c 100644
--- a/server/src/__tests__/adapter-routes.test.ts
+++ b/server/src/__tests__/adapter-routes.test.ts
@@ -45,6 +45,7 @@ const overridingConfigSchemaAdapter: ServerAdapterModule = {
 
 let registerServerAdapter: typeof import("../adapters/registry.js").registerServerAdapter;
 let unregisterServerAdapter: typeof import("../adapters/registry.js").unregisterServerAdapter;
+let findServerAdapter: typeof import("../adapters/registry.js").findServerAdapter;
 let setOverridePaused: typeof import("../adapters/registry.js").setOverridePaused;
 let adapterRoutes: typeof import("../routes/adapters.js").adapterRoutes;
 let errorHandler: typeof import("../middleware/index.js").errorHandler;
@@ -107,6 +108,7 @@ describe("adapter routes", () => {
     ]);
     registerServerAdapter = registry.registerServerAdapter;
     unregisterServerAdapter = registry.unregisterServerAdapter;
+    findServerAdapter = registry.findServerAdapter;
     setOverridePaused = registry.setOverridePaused;
     adapterRoutes = routes.adapterRoutes;
     errorHandler = middleware.errorHandler;
@@ -236,4 +238,44 @@ describe("adapter routes", () => {
 
     expect(res.status, JSON.stringify(res.body)).toBe(403);
   });
+
+  it("POST /api/adapters/install preserves module-provided sessionManagement (hot-install parity with init-time IIFE)", async () => {
+    const HOT_INSTALL_TYPE = "hot_install_session_test";
+    const declaredSessionManagement = {
+      supportsSessionResume: true,
+      nativeContextManagement: "confirmed" as const,
+      defaultSessionCompaction: {
+        enabled: true,
+        maxSessionRuns: 10,
+        maxRawInputTokens: 100_000,
+        maxSessionAgeHours: 24,
+      },
+    };
+    const externalModule: ServerAdapterModule = {
+      type: HOT_INSTALL_TYPE,
+      execute: async () => ({ exitCode: 0, signal: null, timedOut: false }),
+      testEnvironment: async () => ({
+        adapterType: HOT_INSTALL_TYPE,
+        status: "pass",
+        checks: [],
+        testedAt: new Date(0).toISOString(),
+      }),
+      sessionManagement: declaredSessionManagement,
+    };
+    mockPluginLoader.loadExternalAdapterPackage.mockResolvedValue(externalModule);
+
+    const app = createApp({ isInstanceAdmin: true });
+    const res = await request(app)
+      .post("/api/adapters/install")
+      .send({ packageName: "/tmp/fake-hot-install-adapter", isLocalPath: true });
+
+    expect(res.status, JSON.stringify(res.body)).toBe(201);
+    expect(res.body.type).toBe(HOT_INSTALL_TYPE);
+
+    const registered = findServerAdapter(HOT_INSTALL_TYPE);
+    expect(registered).not.toBeNull();
+    expect(registered?.sessionManagement).toEqual(declaredSessionManagement);
+
+    unregisterServerAdapter(HOT_INSTALL_TYPE);
+  });
 });
diff --git a/server/src/adapters/registry.ts b/server/src/adapters/registry.ts
index 40202edc7c..8268f0629a 100644
--- a/server/src/adapters/registry.ts
+++ b/server/src/adapters/registry.ts
@@ -353,8 +353,10 @@ function getDisabledAdapterTypesFromStore(): string[] {
  * override a built-in — same `type` — inherit the builtin's policy). If
  * neither is available, `sessionManagement` remains `undefined`.
  *
- * Exported for unit tests; runtime callers use the IIFE below, which
- * applies this transformation during the external-adapter load pass.
+ * Used by both the init-time IIFE below (external-adapter load pass on
+ * server start) and the hot-install path in `routes/adapters.ts`
+ * (`registerWithSessionManagement`), so the two load paths resolve
+ * `sessionManagement` identically.
  */
 export function resolveExternalAdapterRegistration(
   externalAdapter: ServerAdapterModule,
diff --git a/server/src/routes/adapters.ts b/server/src/routes/adapters.ts
index 40e5800ef9..efe52b4870 100644
--- a/server/src/routes/adapters.ts
+++ b/server/src/routes/adapters.ts
@@ -25,11 +25,11 @@ import {
   findActiveServerAdapter,
   listEnabledServerAdapters,
   registerServerAdapter,
+  resolveExternalAdapterRegistration,
   unregisterServerAdapter,
   isOverridePaused,
   setOverridePaused,
 } from "../adapters/registry.js";
-import { getAdapterSessionManagement } from "@paperclipai/adapter-utils";
 import {
   listAdapterPlugins,
   addAdapterPlugin,
@@ -168,15 +168,17 @@ async function normalizeLocalPath(rawPath: string): Promise<string> {
 }
 
 /**
- * Register an adapter module into the server registry, filling in
- * sessionManagement from the host.
+ * Register an external adapter module into the server registry via the
+ * hot-install path, resolving `sessionManagement` identically to how the
+ * init-time IIFE does. Module-provided `sessionManagement` is honored first,
+ * with fallback to the host registry by type for builtin-type overrides.
+ *
+ * Keeps the hot-install and init-time paths at parity so an adapter installed
+ * via `POST /api/adapters/install` has the same shape in the registry as the
+ * same adapter loaded on the next server restart.
  */
 function registerWithSessionManagement(adapter: ServerAdapterModule): void {
-  const wrapped: ServerAdapterModule = {
-    ...adapter,
-    sessionManagement: getAdapterSessionManagement(adapter.type) ?? undefined,
-  };
-  registerServerAdapter(wrapped);
+  registerServerAdapter(resolveExternalAdapterRegistration(adapter));
 }
 
 // ---------------------------------------------------------------------------