diff --git a/internal/config/config.go b/internal/config/config.go
index 9d75e160..3e4a912a 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -54,6 +54,9 @@ type MultiAgentConfig struct {
 	// OrchestratorInstructionSupervisor supervisor 主代理系统提示（transfer/exit 说明仍由运行追加）；非空且 agents/orchestrator-supervisor.md 正文为空或未存在时生效。
 	OrchestratorInstructionSupervisor string `yaml:"orchestrator_instruction_supervisor,omitempty" json:"orchestrator_instruction_supervisor,omitempty"`
 	SubAgents                    []MultiAgentSubConfig `yaml:"sub_agents" json:"sub_agents"`
+	// SubAgentUserContextMaxRunes caps the user-context supplement injected into sub-agent instructions.
+	// 0 (default) uses the built-in default of 2000 runes; negative value disables injection entirely.
+	SubAgentUserContextMaxRunes int `yaml:"sub_agent_user_context_max_runes,omitempty" json:"sub_agent_user_context_max_runes,omitempty"`
 	// EinoSkills configures CloudWeGo Eino ADK skill middleware + optional local filesystem/execute on DeepAgent.
 	EinoSkills MultiAgentEinoSkillsConfig `yaml:"eino_skills,omitempty" json:"eino_skills,omitempty"`
 	// EinoMiddleware wires optional ADK middleware (patchtoolcalls, toolsearch, plantask, reduction) and Deep extras.
diff --git a/internal/multiagent/runner.go b/internal/multiagent/runner.go
index ddfbce9c..8efea50b 100644
--- a/internal/multiagent/runner.go
+++ b/internal/multiagent/runner.go
@@ -205,6 +205,9 @@ func RunDeepAgent(
 			if instr == "" {
 				instr = "你是 CyberStrikeAI 中的专业子代理，在授权渗透测试场景下协助完成用户委托的子任务。优先使用可用工具获取证据，回答简洁专业。"
 			}
+			if supplement := buildUserContextForSubAgent(userMessage, history, ma.SubAgentUserContextMaxRunes); supplement != "" {
+				instr += supplement
+			}
 
 			roleTools := sub.RoleTools
 			bind := strings.TrimSpace(sub.BindRole)
diff --git a/internal/multiagent/sub_agent_context.go b/internal/multiagent/sub_agent_context.go
new file mode 100644
index 00000000..bd9e11eb
--- /dev/null
+++ b/internal/multiagent/sub_agent_context.go
@@ -0,0 +1,91 @@
+package multiagent
+
+import (
+	"strings"
+
+	"cyberstrike-ai/internal/agent"
+)
+
+const defaultSubAgentUserContextMaxRunes = 2000
+
+// buildUserContextForSubAgent collects all user messages from conversation
+// history plus the current user message, and returns a formatted string to
+// append to sub-agent instructions. This ensures sub-agents always have
+// access to the full user intent (target URLs, scope, etc.) even when the
+// orchestrator forgets to include them in the task description.
+//
+// maxRunes controls the character budget for the user-context body:
+//   - 0 uses defaultSubAgentUserContextMaxRunes
+//   - negative disables injection (returns "")
+//
+// When truncation is needed, the first and last user messages are each
+// allocated half the budget so neither is lost entirely.
+func buildUserContextForSubAgent(userMessage string, history []agent.ChatMessage, maxRunes int) string {
+	if maxRunes < 0 {
+		return ""
+	}
+	if maxRunes == 0 {
+		maxRunes = defaultSubAgentUserContextMaxRunes
+	}
+
+	var userMsgs []string
+	for _, h := range history {
+		if h.Role == "user" {
+			if m := strings.TrimSpace(h.Content); m != "" {
+				userMsgs = append(userMsgs, m)
+			}
+		}
+	}
+	if um := strings.TrimSpace(userMessage); um != "" {
+		if len(userMsgs) == 0 || userMsgs[len(userMsgs)-1] != um {
+			userMsgs = append(userMsgs, um)
+		}
+	}
+	if len(userMsgs) == 0 {
+		return ""
+	}
+
+	joined := strings.Join(userMsgs, "\n---\n")
+
+	if len([]rune(joined)) > maxRunes {
+		joined = truncateKeepFirstLast(userMsgs, maxRunes)
+	}
+
+	return "\n\n## 本次会话用户原始请求（自动注入，确保你了解完整上下文）\n" + joined
+}
+
+// truncateKeepFirstLast keeps the first and last user messages, giving each
+// half the rune budget. The first message typically contains target info;
+// the last is the current instruction.
+func truncateKeepFirstLast(msgs []string, maxRunes int) string {
+	if len(msgs) == 1 {
+		return truncateRunes(msgs[0], maxRunes)
+	}
+
+	first := msgs[0]
+	last := msgs[len(msgs)-1]
+	sep := "\n---\n...(中间对话省略)...\n---\n"
+	sepLen := len([]rune(sep))
+
+	budget := maxRunes - sepLen
+	if budget <= 0 {
+		return truncateRunes(first+"\n---\n"+last, maxRunes)
+	}
+
+	halfBudget := budget / 2
+	firstTrunc := truncateRunes(first, halfBudget)
+	lastTrunc := truncateRunes(last, budget-len([]rune(firstTrunc)))
+
+	return firstTrunc + sep + lastTrunc
+}
+
+func truncateRunes(s string, max int) string {
+	rs := []rune(s)
+	if len(rs) <= max {
+		return s
+	}
+	if max <= 0 {
+		return ""
+	}
+	return string(rs[:max])
+}
diff --git a/internal/multiagent/sub_agent_context_test.go b/internal/multiagent/sub_agent_context_test.go
new file mode 100644
index 00000000..c2ca21eb
--- /dev/null
+++ b/internal/multiagent/sub_agent_context_test.go
@@ -0,0 +1,117 @@
+package multiagent
+
+import (
+	"strings"
+	"testing"
+
+	"cyberstrike-ai/internal/agent"
+)
+
+func TestBuildUserContextForSubAgent_SingleMessage(t *testing.T) {
+	result := buildUserContextForSubAgent("http://8.163.32.73:8081 测试命令执行", nil, 0)
+	if result == "" {
+		t.Fatal("expected non-empty context")
+	}
+	if !strings.Contains(result, "http://8.163.32.73:8081") {
+		t.Error("expected URL in context")
+	}
+}
+
+func TestBuildUserContextForSubAgent_MultiTurn(t *testing.T) {
+	history := []agent.ChatMessage{
+		{Role: "user", Content: "http://8.163.32.73:8081 这是一个pikachu靶场，尝试测试命令执行"},
+		{Role: "assistant", Content: "好的，我来测试..."},
+		{Role: "user", Content: "继续，并持久化webshell"},
+		{Role: "assistant", Content: "正在处理..."},
+	}
+	result := buildUserContextForSubAgent("你好", history, 0)
+	if !strings.Contains(result, "http://8.163.32.73:8081") {
+		t.Error("expected first turn URL to be preserved")
+	}
+	if !strings.Contains(result, "你好") {
+		t.Error("expected current message in context")
+	}
+}
+
+func TestBuildUserContextForSubAgent_EmptyMessages(t *testing.T) {
+	result := buildUserContextForSubAgent("", nil, 0)
+	if result != "" {
+		t.Errorf("expected empty context, got %q", result)
+	}
+}
+
+func TestBuildUserContextForSubAgent_DeduplicateCurrentMessage(t *testing.T) {
+	history := []agent.ChatMessage{
+		{Role: "user", Content: "你好"},
+	}
+	result := buildUserContextForSubAgent("你好", history, 0)
+	if strings.Count(result, "你好") != 1 {
+		t.Errorf("expected '你好' exactly once, got: %s", result)
+	}
+}
+
+func TestBuildUserContextForSubAgent_SkipsNonUserMessages(t *testing.T) {
+	history := []agent.ChatMessage{
+		{Role: "user", Content: "目标是 10.0.0.1"},
+		{Role: "assistant", Content: "这个不应该出现"},
+		{Role: "user", Content: "开始扫描"},
+	}
+	result := buildUserContextForSubAgent("确认", history, 0)
+	if strings.Contains(result, "这个不应该出现") {
+		t.Error("assistant message should not be included")
+	}
+	if !strings.Contains(result, "10.0.0.1") {
+		t.Error("expected IP from first user message")
+	}
+}
+
+func TestBuildUserContextForSubAgent_TruncatesLongConversation(t *testing.T) {
+	first := "http://target.com " + strings.Repeat("A", 500)
+	var history []agent.ChatMessage
+	history = append(history, agent.ChatMessage{Role: "user", Content: first})
+	for i := 0; i < 10; i++ {
+		history = append(history, agent.ChatMessage{Role: "user", Content: strings.Repeat("B", 500)})
+	}
+	last := "最后一条指令"
+	result := buildUserContextForSubAgent(last, history, 0)
+
+	if !strings.Contains(result, "http://target.com") {
+		t.Error("first message (target URL) should be preserved after truncation")
+	}
+	if !strings.Contains(result, last) {
+		t.Error("last message should be preserved after truncation")
+	}
+}
+
+func TestBuildUserContextForSubAgent_DisabledByNegativeMax(t *testing.T) {
+	result := buildUserContextForSubAgent("http://example.com test", nil, -1)
+	if result != "" {
+		t.Errorf("expected empty when disabled, got %q", result)
+	}
+}
+
+func TestBuildUserContextForSubAgent_CustomMaxRunes(t *testing.T) {
+	msg := strings.Repeat("A", 200)
+	result := buildUserContextForSubAgent(msg, nil, 50)
+	body := strings.TrimPrefix(result, "\n\n## 本次会话用户原始请求（自动注入，确保你了解完整上下文）\n")
+	if len([]rune(body)) > 50 {
+		t.Errorf("body should be capped at 50 runes, got %d", len([]rune(body)))
+	}
+}
+
+func TestTruncateKeepFirstLast_BothPreserved(t *testing.T) {
+	first := strings.Repeat("F", 100)
+	last := strings.Repeat("L", 100)
+	msgs := []string{first, "middle1", "middle2", last}
+	result := truncateKeepFirstLast(msgs, 250)
+
+	if !strings.HasPrefix(result, "FFFF") {
+		t.Error("first message should be at the start")
+	}
+	if !strings.HasSuffix(result, "LLLL") {
+		t.Error("last message should be at the end")
+	}
+	if !strings.Contains(result, "中间对话省略") {
+		t.Error("should contain truncation marker")
+	}
+}