diff --git a/src/commands/agent-via-gateway.test.ts b/src/commands/agent-via-gateway.test.ts
index 8173c40176f..83922ffdc94 100644
--- a/src/commands/agent-via-gateway.test.ts
+++ b/src/commands/agent-via-gateway.test.ts
@@ -5,7 +5,7 @@ import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import type { OpenClawConfig } from "../config/config.js";
 import { loggingState } from "../logging/state.js";
 import type { RuntimeEnv } from "../runtime.js";
-import { agentCliCommand } from "./agent-via-gateway.js";
+import { __testing as agentViaGatewayTesting, agentCliCommand } from "./agent-via-gateway.js";
 import type { agentCommand as AgentCommand } from "./agent.js";
 
 const loadConfig = vi.hoisted(() => vi.fn());
@@ -21,6 +21,7 @@ const isGatewayTransportError = vi.hoisted(() =>
 );
 const agentCommand = vi.hoisted(() => vi.fn());
 const agentModuleLoadCount = vi.hoisted(() => vi.fn());
+const loadAgentSessionModuleMock = vi.hoisted(() => vi.fn());
 
 const runtime: RuntimeEnv = {
   log: vi.fn(),
@@ -147,6 +148,17 @@ async function waitForAgentCommandCall(expectedCalls = 1) {
   expect(agentCommand).toHaveBeenCalledTimes(expectedCalls);
 }
 
+async function waitForGatewayCall(expectedCalls = 1) {
+  for (
+    let attempt = 0;
+    attempt < 50 && callGateway.mock.calls.length < expectedCalls;
+    attempt += 1
+  ) {
+    await new Promise<void>((resolve) => setTimeout(resolve, 0));
+  }
+  expect(callGateway).toHaveBeenCalledTimes(expectedCalls);
+}
+
 function mockMessages(mock: unknown): string[] {
   const calls = (mock as { mock?: { calls?: unknown[][] } }).mock?.calls ?? [];
   return calls.map(([message]) => String(message));
@@ -209,6 +221,9 @@ let originalForceConsoleToStderr = false;
 
 beforeEach(() => {
   vi.clearAllMocks();
+  agentViaGatewayTesting.resetLazyImportsForTests();
+  loadAgentSessionModuleMock.mockImplementation(async () => await import("./agent/session.js"));
+  agentViaGatewayTesting.setAgentSessionModuleLoaderForTests(loadAgentSessionModuleMock);
   originalForceConsoleToStderr = loggingState.forceConsoleToStderr;
   loggingState.forceConsoleToStderr = false;
 });
@@ -270,6 +285,7 @@ describe("agentCliCommand", () => {
       expect(params.sessionId).toBeUndefined();
       expect(params.to).toBeUndefined();
       expect(agentCommand).not.toHaveBeenCalled();
+      expect(loadAgentSessionModuleMock).not.toHaveBeenCalled();
     });
   });
 
@@ -529,7 +545,7 @@ describe("agentCliCommand", () => {
         const run = agentCliCommand({ message: "hi", to: "+1555" }, runtime, {
           process: signals.processLike,
         });
-        await Promise.resolve();
+        await waitForGatewayCall();
         signals.emit(signalName);
         expect(signals.listenerCount("SIGTERM")).toBe(0);
         expect(signals.listenerCount("SIGINT")).toBe(0);
@@ -596,7 +612,7 @@ describe("agentCliCommand", () => {
           process: signals.processLike,
         },
       );
-      await Promise.resolve();
+      await waitForGatewayCall();
       signals.emit("SIGTERM");
 
       await run;
@@ -638,7 +654,7 @@ describe("agentCliCommand", () => {
       const run = agentCliCommand({ message: "hi", to: "+1555" }, runtime, {
         process: signals.processLike,
       });
-      await Promise.resolve();
+      await waitForGatewayCall();
       signals.emit("SIGTERM");
 
       await run;
@@ -702,7 +718,7 @@ describe("agentCliCommand", () => {
           process: signals.processLike,
         },
       );
-      await Promise.resolve();
+      await waitForGatewayCall();
       signals.emit("SIGTERM");
 
       await run;
@@ -778,7 +794,7 @@ describe("agentCliCommand", () => {
           process: signals.processLike,
         },
       );
-      await Promise.resolve();
+      await waitForGatewayCall();
       signals.emit("SIGTERM");
 
       await run;
@@ -856,7 +872,7 @@ describe("agentCliCommand", () => {
           process: signals.processLike,
         },
       );
-      await Promise.resolve();
+      await waitForGatewayCall();
       signals.emit("SIGTERM");
 
       await run;
@@ -932,7 +948,7 @@ describe("agentCliCommand", () => {
           process: signals.processLike,
         },
       );
-      await Promise.resolve();
+      await waitForGatewayCall();
       signals.emit("SIGTERM");
 
       await run;
diff --git a/src/commands/agent-via-gateway.ts b/src/commands/agent-via-gateway.ts
index 238d2159855..2346a3f9274 100644
--- a/src/commands/agent-via-gateway.ts
+++ b/src/commands/agent-via-gateway.ts
@@ -29,7 +29,6 @@ import {
 import { type RuntimeEnv, writeRuntimeJson } from "../runtime.js";
 import { normalizeOptionalString } from "../shared/string-coerce.js";
 import { normalizeMessageChannel } from "../utils/message-channel.js";
-import { buildExplicitSessionIdSessionKey, resolveSessionKeyForRequest } from "./agent/session.js";
 
 type AgentGatewayResult = {
   payloads?: Array<{
@@ -93,6 +92,8 @@ type AgentGatewayCallIdentity = Pick<
   "clientName" | "mode" | "scopes"
 >;
 type EmbeddedAgentCommandModule = typeof import("./agent.js");
+type AgentSessionModule = typeof import("./agent/session.js");
+type AgentSessionModuleLoader = () => Promise<AgentSessionModule>;
 
 const AGENT_CLI_SIGNALS: readonly AgentCliSignal[] = ["SIGINT", "SIGTERM"];
 const GATEWAY_ABORT_RETRY_DELAYS_MS = [50, 150, 300, 600] as const;
@@ -103,12 +104,33 @@ const AGENT_CLI_SIGNAL_EXIT_CODES: Record<AgentCliSignal, number> = {
 };
 
 let embeddedAgentCommandPromise: Promise<EmbeddedAgentCommandModule["agentCommand"]> | undefined;
+let agentSessionModulePromise: Promise<AgentSessionModule> | undefined;
+const defaultAgentSessionModuleLoader: AgentSessionModuleLoader = () =>
+  import("./agent/session.js");
+let agentSessionModuleLoader: AgentSessionModuleLoader = defaultAgentSessionModuleLoader;
 
 function loadEmbeddedAgentCommand(): Promise<EmbeddedAgentCommandModule["agentCommand"]> {
   embeddedAgentCommandPromise ??= import("./agent.js").then((module) => module.agentCommand);
   return embeddedAgentCommandPromise;
 }
 
+function loadAgentSessionModule(): Promise<AgentSessionModule> {
+  agentSessionModulePromise ??= agentSessionModuleLoader();
+  return agentSessionModulePromise;
+}
+
+export const __testing = {
+  resetLazyImportsForTests(): void {
+    embeddedAgentCommandPromise = undefined;
+    agentSessionModulePromise = undefined;
+    agentSessionModuleLoader = defaultAgentSessionModuleLoader;
+  },
+  setAgentSessionModuleLoaderForTests(loader: AgentSessionModuleLoader): void {
+    agentSessionModulePromise = undefined;
+    agentSessionModuleLoader = loader;
+  },
+};
+
 function protectJsonStdout(opts: Pick<AgentCliOpts, "json">): void {
   if (opts.json === true) {
     routeLogsToStderr();
@@ -461,11 +483,13 @@ function createGatewayTimeoutFallbackSession(agentId?: string): {
   const sessionId = createGatewayTimeoutFallbackSessionId();
   return {
     sessionId,
-    sessionKey: buildExplicitSessionIdSessionKey({ sessionId, agentId }),
+    sessionKey: `agent:${normalizeAgentId(agentId)}:explicit:${sessionId.trim()}`,
   };
 }
 
-function resolveAgentIdForGatewayTimeoutFallback(opts: AgentCliOpts): string | undefined {
+async function resolveAgentIdForGatewayTimeoutFallback(
+  opts: AgentCliOpts,
+): Promise<string | undefined> {
   const explicitSessionKey = opts.sessionKey?.trim();
   if (classifySessionKeyShape(explicitSessionKey) === "agent") {
     return resolveAgentIdFromSessionKey(explicitSessionKey);
@@ -483,6 +507,7 @@ function resolveAgentIdForGatewayTimeoutFallback(opts: AgentCliOpts): string | u
     return undefined;
   }
   const cfg = getRuntimeConfig();
+  const { resolveSessionKeyForRequest } = await loadAgentSessionModule();
   const resolvedSessionKey = resolveSessionKeyForRequest({
     cfg,
     to: opts.to,
@@ -550,13 +575,16 @@ async function agentViaGatewayCommand(
       ? NO_GATEWAY_TIMEOUT_MS // no timeout (timer-safe max)
       : Math.max(10_000, (timeoutSeconds + 30) * 1000);
 
-  const sessionKey = resolveSessionKeyForRequest({
-    cfg,
-    agentId,
-    to: opts.to,
-    sessionId: opts.sessionId,
-    sessionKey: explicitSessionKey,
-  }).sessionKey;
+  const sessionKey =
+    classifySessionKeyShape(explicitSessionKey) === "agent"
+      ? explicitSessionKey
+      : (await loadAgentSessionModule()).resolveSessionKeyForRequest({
+          cfg,
+          agentId,
+          to: opts.to,
+          sessionId: opts.sessionId,
+          sessionKey: explicitSessionKey,
+        }).sessionKey;
 
   const channel = normalizeMessageChannel(opts.channel);
   const idempotencyKey = normalizeOptionalString(opts.runId) || randomIdempotencyKey();
@@ -750,7 +778,7 @@ export async function agentCliCommand(
         if (isControlCommandThatMustNotFallback(dispatchOpts)) {
           throw err;
         }
-        const fallbackAgentId = resolveAgentIdForGatewayTimeoutFallback(dispatchOpts);
+        const fallbackAgentId = await resolveAgentIdForGatewayTimeoutFallback(dispatchOpts);
         const fallbackSession = createGatewayTimeoutFallbackSession(fallbackAgentId);
         runtime.error?.(
           `EMBEDDED FALLBACK: Gateway agent timed out; running embedded agent with fresh session ${fallbackSession.sessionId}: ${String(err)}`,