diff --git a/apps/cli/src/ai/tool-adapter.ts b/apps/cli/src/ai/tool-adapter.ts
index a55dbbce..b20505b1 100644
--- a/apps/cli/src/ai/tool-adapter.ts
+++ b/apps/cli/src/ai/tool-adapter.ts
@@ -21,7 +21,6 @@ import { getServerAiLogger } from './logger'
 const DEFAULT_MAX_TOOL_RESULT_TOKENS = 8000
 
 const TOOL_TRUNCATION_STRATEGY: Record<string, TruncationStrategy> = {
-  search_keyword: 'keep_first',
   search_messages: 'keep_first',
   deep_search_messages: 'keep_first',
   get_recent_messages: 'keep_last',
diff --git a/packages/mcp-server/src/server.ts b/packages/mcp-server/src/server.ts
index 6fd35968..3786f3cb 100644
--- a/packages/mcp-server/src/server.ts
+++ b/packages/mcp-server/src/server.ts
@@ -17,10 +17,7 @@ import { formatToolResultAsText } from './format'
 
 const MCP_TOOL_PREFIX = 'chatlab_'
 
-const FORMAT_PARAM = z
-  .enum(['text', 'json'])
-  .optional()
-  .describe('Output format: "text" for token-efficient plain text (default), "json" for structured JSON')
+const FORMAT_PARAM = z.enum(['text', 'json']).optional().describe('text (default) or json')
 
 /** Tools where JSON is a better default (raw SQL results, schema) */
 const JSON_DEFAULT_TOOLS = new Set(['execute_sql', 'get_schema'])
@@ -60,9 +57,8 @@ function registerTools(server: McpServer, dbManager: McpDatabaseManager): void {
       continue
     }
 
-    const sessionsToolMcpName = `${MCP_TOOL_PREFIX}list_sessions`
     const zodShape = {
-      session_id: z.string().describe(`Session ID (use ${sessionsToolMcpName} to get available sessions)`),
+      session_id: z.string().describe('Session ID'),
       ...jsonSchemaToZod(tool.inputSchema.properties, tool.inputSchema.required),
       format: FORMAT_PARAM,
     }
diff --git a/packages/tools/src/index.ts b/packages/tools/src/index.ts
index bcb2a638..d6651cae 100644
--- a/packages/tools/src/index.ts
+++ b/packages/tools/src/index.ts
@@ -14,7 +14,7 @@ export { CoreDataProvider } from './providers/core-data-provider'
 // === Tool Definitions ===
 export { memberStatsTool } from './definitions/member-stats'
 export { timeStatsTool } from './definitions/time-stats'
-export { searchTool } from './definitions/search'
+
 export { recentMessagesTool } from './definitions/recent-messages'
 export { sqlQueryTool, schemaTool } from './definitions/sql-query'
 export { chatOverviewTool } from './definitions/chat-overview'
diff --git a/packages/tools/src/registry.ts b/packages/tools/src/registry.ts
index cf2a01ff..f5250bed 100644
--- a/packages/tools/src/registry.ts
+++ b/packages/tools/src/registry.ts
@@ -1,14 +1,15 @@
 /**
- * 工具注册表
+ * Tool registries
  *
- * AGENT_TOOL_REGISTRY: Agent 共用（Server Agent / Electron Agent），
- *   与 Electron TOOL_REGISTRY 保持一致的完整工具集。
- * MCP_TOOL_REGISTRY: MCP Server 使用，包含 Agent 全量工具 + MCP 特有的会话发现工具。
+ * AGENT_TOOL_REGISTRY: full toolset for Server Agent / Electron Agent
+ *   (core + analysis + raw SQL + declarative SQL tools).
+ * MCP_TOOL_REGISTRY: slim toolset for MCP Server — core + analysis + raw SQL
+ *   plus MCP-specific session-discovery tools. Omits declarative SQL tools
+ *   to keep tool-schema token cost low for external AI agents.
  */
 
 import type { ToolDefinition } from './types'
 
-import { searchTool } from './definitions/search'
 import { sqlQueryTool, schemaTool } from './definitions/sql-query'
 import { sessionInfoTool } from './definitions/session-info'
 import { sessionsListTool } from './definitions/sessions'
@@ -30,12 +31,10 @@ import { keywordFrequencyTool } from './definitions/keyword-frequency'
 import { SQL_TOOL_DEFS, createAllSqlToolDefinitions } from './sql'
 
 /**
- * Agent 共用注册表
- *
- * 与 Electron TOOL_REGISTRY 完全对齐的工具集，在"已选定会话"上下文中使用。
- * 不包含 MCP 特有的会话发现工具（list_sessions、get_session_info、search_keyword）。
+ * Core + analysis + raw SQL — shared between Agent and MCP.
+ * New non-SQL tools added here will automatically appear in both registries.
  */
-export const AGENT_TOOL_REGISTRY: ToolDefinition[] = [
+const SHARED_TOOLS: ToolDefinition[] = [
   // Core
   chatOverviewTool,
   searchMessagesTool,
@@ -55,25 +54,30 @@ export const AGENT_TOOL_REGISTRY: ToolDefinition[] = [
   responseTimeAnalysisTool,
   keywordFrequencyTool,
 
-  // SQL
+  // Raw SQL
   sqlQueryTool,
-  ...createAllSqlToolDefinitions(SQL_TOOL_DEFS),
 ]
 
 /**
- * MCP Server 注册表
+ * Agent full toolset (Server Agent / Electron Agent).
+ * Includes declarative SQL convenience tools on top of the shared set.
+ */
+export const AGENT_TOOL_REGISTRY: ToolDefinition[] = [...SHARED_TOOLS, ...createAllSqlToolDefinitions(SQL_TOOL_DEFS)]
+
+/**
+ * MCP Server toolset — slim registry optimised for external AI agents.
  *
- * 包含 MCP 特有工具（会话发现、schema）以及完整的 Agent 工具集。
- * MCP 层自动为非 list_sessions 工具注入 session_id 参数。
+ * Includes MCP-specific session-discovery tools + shared core/analysis tools.
+ * Omits declarative SQL tools to reduce tool-schema token overhead (~40% saving).
+ * LLMs can use execute_sql + get_schema for any custom query.
  */
 export const MCP_TOOL_REGISTRY: ToolDefinition[] = [
   // MCP-specific: session discovery & schema
   sessionsListTool,
   sessionInfoTool,
-  searchTool,
   schemaTool,
-  // Full agent toolset
-  ...AGENT_TOOL_REGISTRY,
+  // Shared core + analysis + raw SQL
+  ...SHARED_TOOLS,
 ]
 
 /**