diff --git a/src/gateway/tools-invoke-http.ts b/src/gateway/tools-invoke-http.ts
index fa45bf3dc..bf05e2822 100644
--- a/src/gateway/tools-invoke-http.ts
+++ b/src/gateway/tools-invoke-http.ts
@@ -18,6 +18,7 @@ import {
 import { loadConfig } from "../config/config.js";
 import { resolveMainSessionKey } from "../config/sessions.js";
 import { logWarn } from "../logger.js";
+import { isTestDefaultMemorySlotDisabled } from "../plugins/config-state.js";
 import { getPluginToolMeta } from "../plugins/tools.js";
 import { isSubagentSessionKey } from "../routing/session-key.js";
 import { normalizeMessageChannel } from "../utils/message-channel.js";
@@ -33,6 +34,7 @@ import {
 } from "./http-common.js";
 
 const DEFAULT_BODY_BYTES = 2 * 1024 * 1024;
+const MEMORY_TOOL_NAMES = new Set(["memory_search", "memory_get"]);
 
 type ToolsInvokeBody = {
   tool?: unknown;
@@ -47,6 +49,26 @@ function resolveSessionKeyFromBody(body: ToolsInvokeBody): string | undefined {
   return undefined;
 }
 
+function resolveMemoryToolDisableReasons(cfg: ReturnType<typeof loadConfig>): string[] {
+  if (!process.env.VITEST) return [];
+  const reasons: string[] = [];
+  const plugins = cfg.plugins;
+  const slotRaw = plugins?.slots?.memory;
+  const slotDisabled =
+    slotRaw === null || (typeof slotRaw === "string" && slotRaw.trim().toLowerCase() === "none");
+  const pluginsDisabled = plugins?.enabled === false;
+  const defaultDisabled = isTestDefaultMemorySlotDisabled(cfg);
+
+  if (pluginsDisabled) reasons.push("plugins.enabled=false");
+  if (slotDisabled) {
+    reasons.push(slotRaw === null ? "plugins.slots.memory=null" : 'plugins.slots.memory="none"');
+  }
+  if (!pluginsDisabled && !slotDisabled && defaultDisabled) {
+    reasons.push("memory plugin disabled by test default");
+  }
+  return reasons;
+}
+
 function mergeActionIntoArgsIfSupported(params: {
   toolSchema: unknown;
   action: string | undefined;
@@ -103,6 +125,23 @@ export async function handleToolsInvokeHttpRequest(
     return true;
   }
 
+  if (process.env.VITEST && MEMORY_TOOL_NAMES.has(toolName)) {
+    const reasons = resolveMemoryToolDisableReasons(cfg);
+    if (reasons.length > 0) {
+      const suffix = reasons.length > 0 ? ` (${reasons.join(", ")})` : "";
+      sendJson(res, 400, {
+        ok: false,
+        error: {
+          type: "invalid_request",
+          message:
+            `memory tools are disabled in tests${suffix}. ` +
+            'Enable by setting plugins.slots.memory="memory-core" (and ensure plugins.enabled is not false).',
+        },
+      });
+      return true;
+    }
+  }
+
   const action = typeof body.action === "string" ? body.action.trim() : undefined;
 
   const argsRaw = body.args;
diff --git a/src/plugins/config-state.ts b/src/plugins/config-state.ts
index bf44b5fe4..6b1a6c54a 100644
--- a/src/plugins/config-state.ts
+++ b/src/plugins/config-state.ts
@@ -64,6 +64,72 @@ export const normalizePluginsConfig = (
   };
 };
 
+const hasExplicitMemorySlot = (plugins?: MoltbotConfig["plugins"]) =>
+  Boolean(plugins?.slots && Object.prototype.hasOwnProperty.call(plugins.slots, "memory"));
+
+const hasExplicitMemoryEntry = (plugins?: MoltbotConfig["plugins"]) =>
+  Boolean(plugins?.entries && Object.prototype.hasOwnProperty.call(plugins.entries, "memory-core"));
+
+const hasExplicitPluginConfig = (plugins?: MoltbotConfig["plugins"]) => {
+  if (!plugins) return false;
+  if (typeof plugins.enabled === "boolean") return true;
+  if (Array.isArray(plugins.allow) && plugins.allow.length > 0) return true;
+  if (Array.isArray(plugins.deny) && plugins.deny.length > 0) return true;
+  if (plugins.load?.paths && Array.isArray(plugins.load.paths) && plugins.load.paths.length > 0)
+    return true;
+  if (plugins.slots && Object.keys(plugins.slots).length > 0) return true;
+  if (plugins.entries && Object.keys(plugins.entries).length > 0) return true;
+  return false;
+};
+
+export function applyTestPluginDefaults(
+  cfg: MoltbotConfig,
+  env: NodeJS.ProcessEnv = process.env,
+): MoltbotConfig {
+  if (!env.VITEST) return cfg;
+  const plugins = cfg.plugins;
+  const explicitConfig = hasExplicitPluginConfig(plugins);
+  if (explicitConfig) {
+    if (hasExplicitMemorySlot(plugins) || hasExplicitMemoryEntry(plugins)) {
+      return cfg;
+    }
+    return {
+      ...cfg,
+      plugins: {
+        ...plugins,
+        slots: {
+          ...plugins?.slots,
+          memory: null,
+        },
+      },
+    };
+  }
+
+  return {
+    ...cfg,
+    plugins: {
+      ...plugins,
+      enabled: false,
+      slots: {
+        ...plugins?.slots,
+        memory: null,
+      },
+    },
+  };
+}
+
+export function isTestDefaultMemorySlotDisabled(
+  cfg: MoltbotConfig,
+  env: NodeJS.ProcessEnv = process.env,
+): boolean {
+  if (!env.VITEST) return false;
+  const plugins = cfg.plugins;
+  if (hasExplicitMemorySlot(plugins) || hasExplicitMemoryEntry(plugins)) {
+    return false;
+  }
+  return true;
+}
+
 export function resolveEnableState(
   id: string,
   origin: PluginRecord["origin"],
diff --git a/src/plugins/loader.ts b/src/plugins/loader.ts
index 174441bfc..79c785f27 100644
--- a/src/plugins/loader.ts
+++ b/src/plugins/loader.ts
@@ -10,6 +10,7 @@ import { resolveUserPath } from "../utils.js";
 import { discoverMoltbotPlugins } from "./discovery.js";
 import { loadPluginManifestRegistry } from "./manifest-registry.js";
 import {
+  applyTestPluginDefaults,
   normalizePluginsConfig,
   resolveEnableState,
   resolveMemorySlotDecision,
@@ -162,7 +163,7 @@ function pushDiagnostics(diagnostics: PluginDiagnostic[], append: PluginDiagnost
 }
 
 export function loadMoltbotPlugins(options: PluginLoadOptions = {}): PluginRegistry {
-  const cfg = options.config ?? {};
+  const cfg = applyTestPluginDefaults(options.config ?? {});
   const logger = options.logger ?? defaultLogger();
   const validateOnly = options.mode === "validate";
   const normalized = normalizePluginsConfig(cfg.plugins);