diff --git a/src/costrict/agents/strictPlan.ts b/src/costrict/agents/strictPlan.ts
index 08c716dc4..6ddfd6b5f 100644
--- a/src/costrict/agents/strictPlan.ts
+++ b/src/costrict/agents/strictPlan.ts
@@ -235,5 +235,8 @@ export const STRICT_PLAN_AGENT: BuiltInAgentDefinition = {
   baseDir: 'built-in',
   model: 'inherit',
   omitClaudeMd: false,
+  // 通过斜杠命令从主线程启动时，使 resolveAgentTools 跳过 filterToolsForAgent，
+  // 从而保留主线程完整工具集（包括 Agent 工具）。
+  isMainThread: true,
   getSystemPrompt: () => getStrictPlanSystemPrompt(),
 }
diff --git a/src/tools/AgentTool/agentToolUtils.ts b/src/tools/AgentTool/agentToolUtils.ts
index 084ac6a85..c14c48214 100644
--- a/src/tools/AgentTool/agentToolUtils.ts
+++ b/src/tools/AgentTool/agentToolUtils.ts
@@ -122,7 +122,7 @@ export function filterToolsForAgent({
 export function resolveAgentTools(
   agentDefinition: Pick<
     AgentDefinition,
-    'tools' | 'disallowedTools' | 'source' | 'permissionMode'
+    'tools' | 'disallowedTools' | 'source' | 'permissionMode' | 'isMainThread'
   >,
   availableTools: Tools,
   isAsync = false,
@@ -133,11 +133,15 @@ export function resolveAgentTools(
     disallowedTools,
     source,
     permissionMode,
+    isMainThread: agentIsMainThread,
   } = agentDefinition
-  // When isMainThread is true, skip filterToolsForAgent entirely — the main
-  // thread's tool pool is already properly assembled by useMergedTools(), so
+  // Allow the agent definition itself to declare isMainThread=true,
+  // which takes precedence over the isMainThread parameter.
+  const effectiveIsMainThread = agentIsMainThread ?? isMainThread
+  // When effectiveIsMainThread is true, skip filterToolsForAgent entirely — the
+  // main thread's tool pool is already properly assembled by useMergedTools(), so
   // the sub-agent disallow lists shouldn't apply.
-  const filteredAvailableTools = isMainThread
+  const filteredAvailableTools = effectiveIsMainThread
     ? availableTools
     : filterToolsForAgent({
         tools: availableTools,
@@ -195,7 +199,7 @@ export function resolveAgentTools(
       }
       // For sub-agents, Agent is excluded by filterToolsForAgent — mark the spec
       // valid for allowedAgentTypes tracking but skip tool resolution.
-      if (!isMainThread) {
+      if (!effectiveIsMainThread) {
         validTools.push(toolSpec)
         continue
       }
diff --git a/src/tools/AgentTool/loadAgentsDir.ts b/src/tools/AgentTool/loadAgentsDir.ts
index cb4dc35e2..5336f45ea 100644
--- a/src/tools/AgentTool/loadAgentsDir.ts
+++ b/src/tools/AgentTool/loadAgentsDir.ts
@@ -130,6 +130,10 @@ export type BaseAgentDefinition = {
    * full CLAUDE.md and interprets their output. Saves ~5-15 Gtok/week across
    * 34M+ Explore spawns. Kill-switch: tengu_slim_subagent_claudemd. */
   omitClaudeMd?: boolean
+  /** When true, resolveAgentTools skips filterToolsForAgent so the agent
+   * receives the full main-thread tool pool (including Agent tool).
+   * Use for agents launched directly via slash command from the main thread. */
+  isMainThread?: boolean
 }
 
 // Built-in agents - dynamic prompts only, no static systemPrompt field