diff --git a/src/config/agent-list-projection.ts b/src/config/agent-list-projection.ts
new file mode 100644
index 000000000000..995b15f831b9
--- /dev/null
+++ b/src/config/agent-list-projection.ts
@@ -0,0 +1,17 @@
+import { listAgentEntries } from "../agents/agent-scope.js";
+import type { OpenClawConfig } from "./types.js";
+
+/** Attach the non-serialized list projection used by legacy runtime consumers. */
+export function attachAgentListProjection(config: OpenClawConfig): OpenClawConfig {
+  const agents = config.agents;
+  if (!agents || typeof agents !== "object" || Array.isArray(agents)) {
+    return config;
+  }
+  Object.defineProperty(agents, "list", {
+    configurable: true,
+    enumerable: false,
+    value: listAgentEntries(config),
+    writable: false,
+  });
+  return config;
+}
diff --git a/src/config/runtime-overrides.test.ts b/src/config/runtime-overrides.test.ts
index 5ab42c74d11d..2a0cf02ecdf4 100644
--- a/src/config/runtime-overrides.test.ts
+++ b/src/config/runtime-overrides.test.ts
@@ -1,5 +1,6 @@
 // Covers runtime config overrides and precedence.
 import { beforeEach, describe, expect, it } from "vitest";
+import { listAgentWorkspaceDirs } from "../agents/workspace-dirs.js";
 import {
   applyConfigOverrides,
   captureConfigOverrideApplier,
@@ -8,7 +9,9 @@ import {
   setConfigOverride,
   unsetConfigOverride,
 } from "./runtime-overrides.js";
+import { resolveMainSessionKey } from "./sessions/main-session.js";
 import type { OpenClawConfig } from "./types.js";
+import { validateConfigObject } from "./validation.js";
 
 describe("runtime overrides", () => {
   beforeEach(() => {
@@ -33,6 +36,44 @@ describe("runtime overrides", () => {
     expect(applyConfigOverrides({}).gateway?.auth?.token).toBe("later-token");
   });
 
+  it("preserves the validated agent projection when an override copies agents", () => {
+    const validated = validateConfigObject({
+      agents: {
+        entries: {
+          jarvis: {
+            default: true,
+            workspace: "/tmp/jarvis-workspace",
+          },
+          worker: {
+            workspace: "/tmp/worker-workspace",
+          },
+        },
+      },
+    });
+    if (!validated.ok) {
+      throw new Error("expected valid keyed agent config");
+    }
+
+    const override = setConfigOverride("agents.defaults.model", "test/model");
+    expect(override.ok).toBe(true);
+    const applyCapturedOverrides = captureConfigOverrideApplier();
+    const runtimeConfigs = [
+      applyConfigOverrides(validated.config),
+      applyCapturedOverrides(validated.config),
+    ];
+
+    for (const runtimeConfig of runtimeConfigs) {
+      expect(runtimeConfig.agents).not.toBe(validated.config.agents);
+      expect(runtimeConfig.agents?.list?.map((entry) => entry.id)).toEqual(["jarvis", "worker"]);
+      expect(Object.keys(runtimeConfig.agents ?? {})).not.toContain("list");
+      expect(listAgentWorkspaceDirs(runtimeConfig)).toEqual([
+        "/tmp/jarvis-workspace",
+        "/tmp/worker-workspace",
+      ]);
+      expect(resolveMainSessionKey(runtimeConfig)).toBe("agent:jarvis:main");
+    }
+  });
+
   it("merges object overrides without clobbering siblings", () => {
     const cfg = {
       channels: { whatsapp: { dmPolicy: "pairing", allowFrom: ["+1"] } },
diff --git a/src/config/runtime-overrides.ts b/src/config/runtime-overrides.ts
index d44bf4ea0cc1..a68d07906da8 100644
--- a/src/config/runtime-overrides.ts
+++ b/src/config/runtime-overrides.ts
@@ -2,6 +2,7 @@ import { err, ok, type Result } from "@openclaw/normalization-core/result";
 import { isBlockedObjectKey } from "../infra/prototype-keys.js";
 // Applies runtime-only config overrides without mutating persisted config.
 import { isPlainObject } from "../utils.js";
+import { attachAgentListProjection } from "./agent-list-projection.js";
 import { parseConfigPath, setConfigValueAtPath, unsetConfigValueAtPath } from "./config-paths.js";
 import type { OpenClawConfig } from "./types.js";
 
@@ -46,6 +47,14 @@ function mergeOverrides(base: unknown, override: unknown): unknown {
   return next;
 }
 
+function applyOverrideTree(cfg: OpenClawConfig, overrideTree: OverrideTree): OpenClawConfig {
+  const next = mergeOverrides(cfg, overrideTree) as OpenClawConfig;
+  if (next.agents === cfg.agents) {
+    return next;
+  }
+  return attachAgentListProjection(next);
+}
+
 /** Return the process-local runtime override tree used by debug config commands. */
 export function getConfigOverrides(): OverrideTree {
   return overrides;
@@ -81,7 +90,7 @@ export function applyConfigOverrides(cfg: OpenClawConfig): OpenClawConfig {
   if (!overrides || Object.keys(overrides).length === 0) {
     return cfg;
   }
-  return mergeOverrides(cfg, overrides) as OpenClawConfig;
+  return applyOverrideTree(cfg, overrides);
 }
 
 /** Capture an immutable applier for the process-local overrides active at this instant. */
@@ -90,5 +99,5 @@ export function captureConfigOverrideApplier(): (cfg: OpenClawConfig) => OpenCla
   if (Object.keys(capturedOverrides).length === 0) {
     return (cfg) => cfg;
   }
-  return (cfg) => mergeOverrides(cfg, capturedOverrides) as OpenClawConfig;
+  return (cfg) => applyOverrideTree(cfg, capturedOverrides);
 }
diff --git a/src/config/validation-core.ts b/src/config/validation-core.ts
index 1db01fc429f5..c469aed59759 100644
--- a/src/config/validation-core.ts
+++ b/src/config/validation-core.ts
@@ -3,7 +3,6 @@ import { isCanonicalDottedDecimalIPv4, isLoopbackIpAddress } from "@openclaw/net
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { sanitizeForLog } from "../../packages/terminal-core/src/ansi.js";
 import {
-  listAgentEntries,
   listAgentEntriesWithSource,
   resolveAgentWorkspaceDir,
   resolveDefaultAgentId,
@@ -22,6 +21,7 @@ import {
 } from "../shared/gateway-tailscale-auth-policy.js";
 import { isRecord } from "../utils.js";
 import { findDuplicateAgentDirs, formatDuplicateAgentDirError } from "./agent-dirs.js";
+import { attachAgentListProjection } from "./agent-list-projection.js";
 import { migratePersistedImplicitMainRoster } from "./legacy.roster.js";
 import { materializeRuntimeConfig } from "./materialize.js";
 import {
@@ -243,19 +243,6 @@ function collectModelPolicyAllowIssues(config: OpenClawConfig): ConfigValidation
   return issues;
 }
 
-function attachAgentListProjection(config: OpenClawConfig): OpenClawConfig {
-  if (!config.agents) {
-    return config;
-  }
-  Object.defineProperty(config.agents, "list", {
-    configurable: true,
-    enumerable: false,
-    value: listAgentEntries(config),
-    writable: false,
-  });
-  return config;
-}
-
 /**
  * Validates config without applying runtime defaults.
  * Use this when you need the raw validated config (e.g., for writing back to file).