fix: 明确告知 agent SearchExtraTools/ExecuteExtraTool 是核心工具，已在工具列表中

- prompts.ts: 核心工具列表显式加入 SearchExtraTools, ExecuteExtraTool
- claude.ts: 非 delta 路径提示强调这两个工具可直接调用
- messages.ts: delta 路径渲染强调这两个工具已在工具列表中
- SearchExtraToolsTool/prompt.ts: 加入完整两步工作流示例
- ExecuteTool/prompt.ts: 加入完整两步工作流示例

packages/builtin-tools/src/tools/ExecuteTool/prompt.ts

@@ -4,23 +4,34 @@ export const DESCRIPTION =
   'ExecuteExtraTool — a first-class core tool that is always loaded and available. Execute any deferred tool by name with parameters. Use it after discovering a tool via SearchExtraTools. This is NOT a remote or external tool — it runs locally with full permissions.'
 
 export function getPrompt(): string {
-  return `ExecuteExtraTool — a first-class core tool, always loaded, always available in your tool list. Runs locally with full permissions — NOT a remote or external tool. You do NOT need to search for it.
+  return `ExecuteExtraTool — always loaded, always available. Runs locally with full permissions — NOT a remote or external tool.
 
-This tool accepts a tool_name and params object, looks up the target tool in the global tool registry, and delegates execution to it. The target tool runs with the same permissions and capabilities as if it were called directly.
+## What it does
+Accepts a tool_name and params, looks up the target tool in the registry, and delegates execution to it. The target tool runs with the same permissions as if called directly.
 
-When to use: After SearchExtraTools discovers a deferred tool name, call this tool with {"tool_name": "<name>", "params": {...}} to invoke it immediately.
-When NOT to use: For core tools already in your tool list (Read, Edit, Write, Bash, Glob, Grep, Agent, WebFetch, WebSearch, Skill, etc.) — call those directly.
+## When to use
+ONLY for deferred tools discovered via SearchExtraTools. Core tools (Read, Edit, Write, Bash, Glob, Grep, Agent, WebFetch, WebSearch, Skill) are always in your tool list — call them directly, NOT through ExecuteExtraTool.
 
-Inputs:
-- tool_name: The exact name of the target tool (string)
-- params: The parameters to pass to the target tool (object)
+## How to call — two-step workflow
 
-If the tool is not found, an error message will be returned suggesting to use SearchExtraTools to discover available tools.
+Step 1: SearchExtraTools discovers the tool name and schema.
+Step 2: This tool executes it.
 
-FAILURE HANDLING — CRITICAL:
-If ExecuteExtraTool returns an error (missing parameters, validation error, permission denied, tool not found, or any other failure), you MUST:
-1. Stop immediately — do NOT retry the same tool.
-2. Do NOT call SearchExtraTools again for the same tool name.
-3. Inform the user about the failure and suggest alternatives.
-Never enter a SearchExtraTools → ExecuteExtraTool retry loop for the same tool.`
+Example — user asks to schedule a cron job:
+  SearchExtraTools({"query": "select:CronCreate"})
+  → Response: "Found deferred tool(s): CronCreate"
+  ExecuteExtraTool({"tool_name": "CronCreate", "params": {"schedule": "*/5 * * * *", "prompt": "check deploy"}})
+  → Response: Cron job created
+
+Example — MCP tool:
+  SearchExtraTools({"query": "select:mcp__slack__send_message"})
+  → Response: "Found deferred tool(s): mcp__slack__send_message"
+  ExecuteExtraTool({"tool_name": "mcp__slack__send_message", "params": {"channel": "C123", "text": "hello"}})
+
+## Inputs
+- tool_name: Exact name of the target tool (string, e.g. "CronCreate", "mcp__slack__send_message")
+- params: Object with the target tool's parameters. Check the tool's schema from SearchExtraTools discover: response.
+
+## Failure handling
+If this tool returns an error, do NOT retry or re-search. Tell the user what failed and suggest alternatives.`
 }

packages/builtin-tools/src/tools/SearchExtraToolsTool/prompt.ts

@@ -25,16 +25,39 @@ function getToolLocationHint(): string {
 
 const PROMPT_TAIL = ` Returns matching tool names.
 
-IMPORTANT: ExecuteExtraTool is always available in your tool list. After this search returns tool names, you MUST call ExecuteExtraTool with {"tool_name": "<returned_name>", "params": {...}} to invoke the deferred tool. This is the ONLY way to execute deferred tools — do not read source code or analyze whether the tool is callable, just use ExecuteExtraTool directly.
+## Two-step workflow (MUST follow exactly)
 
-FAILURE RETRY POLICY:
-If ExecuteExtraTool fails for a tool, do NOT search for that same tool again. Searching again will not fix the failure — it will only repeat the same error in a loop. Stop immediately and inform the user about the failure.
+Deferred tools CANNOT be called directly. You MUST use this two-step pattern:
 
-Query forms:
-- "select:CronCreate,Snip" — fetch these exact tools by name
-- "discover:schedule cron job" — pure discovery, returns tool info (name, description) without loading. Use when you want to understand available tools before deciding which to invoke.
+Step 1 — Search: Call this tool (SearchExtraTools) to discover the target tool.
+  Input: {"query": "select:CronCreate"}
+  Response: "Found 1 deferred tool(s): CronCreate. Use ExecuteExtraTool with {"tool_name": "<name>", "params": {...}} to invoke."
+
+Step 2 — Execute: Call ExecuteExtraTool to run the discovered tool.
+  Input: {"tool_name": "CronCreate", "params": {"schedule": "*/5 * * * *", "prompt": "check the deploy"}}
+  Response: the actual tool result.
+
+## Example: user asks "schedule a cron to check deploy every 5 minutes"
+
+1. SearchExtraTools({"query": "select:CronCreate"})
+   → Response: Found deferred tool CronCreate
+2. ExecuteExtraTool({"tool_name": "CronCreate", "params": {"schedule": "*/5 * * * *", "prompt": "check the deploy"}})
+   → Response: Cron job created successfully
+
+If you don't know the exact tool name, use keyword search first:
+1. SearchExtraTools({"query": "cron schedule"})
+   → Response: Found deferred tool(s): CronCreate
+2. ExecuteExtraTool({"tool_name": "CronCreate", "params": {...}})
+
+## Query forms
+- "select:CronCreate" — exact tool name (fastest, preferred when you know the name from <available-deferred-tools>)
+- "select:CronCreate,CronList" — comma-separated multi-select
+- "discover:schedule cron job" — returns tool name + description + schema without loading. Use to understand a tool before calling it.
 - "notebook jupyter" — keyword search, up to max_results best matches
-- "+slack send" — require "slack" in the name, rank by remaining terms`
+- "+slack send" — require "slack" in the name, rank by remaining terms
+
+## Failure policy
+If ExecuteExtraTool fails, do NOT re-search for the same tool — it will loop. Stop and tell the user what failed.`
 
 /**
  * Check if a tool should be deferred (requires SearchExtraTools to load).