feat: US-011 - Add MessageTool tests

- Added comprehensive test suite for MessageTool (message_test.go)
- 10 test cases covering all acceptance criteria:
  - Success returns SilentResult with proper ForLLM status
  - ForUser is empty (user receives message directly)
  - Failure returns ErrorResult with IsError=true
  - Custom channel/chat_id parameter handling
  - Error scenarios (missing content, no target, not configured)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.ralph/prd.json

@@ -167,7 +167,7 @@
         "go test ./pkg/tools -run TestMessageTool passes"
       ],
       "priority": 11,
-      "passes": false,
+      "passes": true,
       "notes": ""
     },
     {

.ralph/progress.txt

@@ -6,7 +6,7 @@ Tool 返回值结构化重构 - 将 Tool 接口返回值从 (string, error) 改
 
 ## Progress
 
-### Completed (9/21)
+### Completed (10/21)
 
 - US-001: Add ToolResult struct and helper functions
 - US-002: Modify Tool interface to return *ToolResult
@@ -17,6 +17,7 @@ Tool 返回值结构化重构 - 将 Tool 接口返回值从 (string, error) 改
 - US-008: Inject callback into async tools in AgentLoop
 - US-009: State save atomicity - SetLastChannel
 - US-010: Update RecordLastChannel to use atomic save
+- US-011: Refactor MessageTool to use ToolResult
 
 ### In Progress
 
@@ -34,7 +35,7 @@ Tool 返回值结构化重构 - 将 Tool 接口返回值从 (string, error) 改
 | US-008 | Inject callback into async tools in AgentLoop | Completed | |
 | US-009 | State save atomicity - SetLastChannel | Completed | |
 | US-010 | Update RecordLastChannel to use atomic save | Completed | |
-| US-011 | Refactor MessageTool to use ToolResult | Completed | |
+| US-011 | Refactor MessageTool to use ToolResult | Completed | Added test file message_test.go |
 | US-012 | Refactor ShellTool to use ToolResult | Completed | |
 | US-013 | Refactor FilesystemTool to use ToolResult | Completed | |
 | US-014 | Refactor WebTool to use ToolResult | Completed | |
@@ -197,3 +198,25 @@ Tool 返回值结构化重构 - 将 Tool 接口返回值从 (string, error) 改
   - **Useful context:** `RecordLastChannel` 方法现在可以用于跟踪用户最后一次活跃的频道，这对于跨会话的上下文恢复很有用。
 
 ---
+
+## [2026-02-12] - US-011
+- What was implemented:
+  - MessageTool 已经完全使用 ToolResult 返回值（无需修改实现）
+  - 添加了完整的测试文件 `pkg/tools/message_test.go`，包含 10 个测试用例
+  - 测试覆盖了所有验收标准：
+    - 发送成功返回 SilentResult（Silent=true）
+    - ForLLM 包含发送状态描述
+    - ForUser 为空（用户已直接收到消息）
+    - 发送失败返回 ErrorResult（IsError=true）
+  - 支持自定义 channel/chat_id 参数
+  - 支持错误场景（缺少 content、无目标 channel、未配置回调）
+
+- Files changed:
+  - `pkg/tools/message_test.go` (新增)
+
+- **Learnings for future iterations:**
+  - **Patterns discovered:** MessageTool 实现已经符合 ToolResult 规范，只需要添加测试覆盖即可。
+  - **Gotchas encountered:** 测试文件使用 `map[string]interface{}` 作为 args 参数类型，与 Tool.Execute 签名一致。
+  - **Useful context:** MessageTool 的设计模式是"用户已直接收到消息，所以 ForUser 为空且 Silent=true"，避免重复发送。
+
+---

pkg/tools/message_test.go

@@ -0,0 +1,259 @@
+package tools
+
+import (
+	"context"
+	"errors"
+	"testing"
+)
+
+func TestMessageTool_Execute_Success(t *testing.T) {
+	tool := NewMessageTool()
+	tool.SetContext("test-channel", "test-chat-id")
+
+	var sentChannel, sentChatID, sentContent string
+	tool.SetSendCallback(func(channel, chatID, content string) error {
+		sentChannel = channel
+		sentChatID = chatID
+		sentContent = content
+		return nil
+	})
+
+	ctx := context.Background()
+	args := map[string]interface{}{
+		"content": "Hello, world!",
+	}
+
+	result := tool.Execute(ctx, args)
+
+	// Verify message was sent with correct parameters
+	if sentChannel != "test-channel" {
+		t.Errorf("Expected channel 'test-channel', got '%s'", sentChannel)
+	}
+	if sentChatID != "test-chat-id" {
+		t.Errorf("Expected chatID 'test-chat-id', got '%s'", sentChatID)
+	}
+	if sentContent != "Hello, world!" {
+		t.Errorf("Expected content 'Hello, world!', got '%s'", sentContent)
+	}
+
+	// Verify ToolResult meets US-011 criteria:
+	// - Send success returns SilentResult (Silent=true)
+	if !result.Silent {
+		t.Error("Expected Silent=true for successful send")
+	}
+
+	// - ForLLM contains send status description
+	if result.ForLLM != "Message sent to test-channel:test-chat-id" {
+		t.Errorf("Expected ForLLM 'Message sent to test-channel:test-chat-id', got '%s'", result.ForLLM)
+	}
+
+	// - ForUser is empty (user already received message directly)
+	if result.ForUser != "" {
+		t.Errorf("Expected ForUser to be empty, got '%s'", result.ForUser)
+	}
+
+	// - IsError should be false
+	if result.IsError {
+		t.Error("Expected IsError=false for successful send")
+	}
+}
+
+func TestMessageTool_Execute_WithCustomChannel(t *testing.T) {
+	tool := NewMessageTool()
+	tool.SetContext("default-channel", "default-chat-id")
+
+	var sentChannel, sentChatID string
+	tool.SetSendCallback(func(channel, chatID, content string) error {
+		sentChannel = channel
+		sentChatID = chatID
+		return nil
+	})
+
+	ctx := context.Background()
+	args := map[string]interface{}{
+		"content": "Test message",
+		"channel": "custom-channel",
+		"chat_id": "custom-chat-id",
+	}
+
+	result := tool.Execute(ctx, args)
+
+	// Verify custom channel/chatID were used instead of defaults
+	if sentChannel != "custom-channel" {
+		t.Errorf("Expected channel 'custom-channel', got '%s'", sentChannel)
+	}
+	if sentChatID != "custom-chat-id" {
+		t.Errorf("Expected chatID 'custom-chat-id', got '%s'", sentChatID)
+	}
+
+	if !result.Silent {
+		t.Error("Expected Silent=true")
+	}
+	if result.ForLLM != "Message sent to custom-channel:custom-chat-id" {
+		t.Errorf("Expected ForLLM 'Message sent to custom-channel:custom-chat-id', got '%s'", result.ForLLM)
+	}
+}
+
+func TestMessageTool_Execute_SendFailure(t *testing.T) {
+	tool := NewMessageTool()
+	tool.SetContext("test-channel", "test-chat-id")
+
+	sendErr := errors.New("network error")
+	tool.SetSendCallback(func(channel, chatID, content string) error {
+		return sendErr
+	})
+
+	ctx := context.Background()
+	args := map[string]interface{}{
+		"content": "Test message",
+	}
+
+	result := tool.Execute(ctx, args)
+
+	// Verify ToolResult for send failure:
+	// - Send failure returns ErrorResult (IsError=true)
+	if !result.IsError {
+		t.Error("Expected IsError=true for failed send")
+	}
+
+	// - ForLLM contains error description
+	expectedErrMsg := "sending message: network error"
+	if result.ForLLM != expectedErrMsg {
+		t.Errorf("Expected ForLLM '%s', got '%s'", expectedErrMsg, result.ForLLM)
+	}
+
+	// - Err field should contain original error
+	if result.Err == nil {
+		t.Error("Expected Err to be set")
+	}
+	if result.Err != sendErr {
+		t.Errorf("Expected Err to be sendErr, got %v", result.Err)
+	}
+}
+
+func TestMessageTool_Execute_MissingContent(t *testing.T) {
+	tool := NewMessageTool()
+	tool.SetContext("test-channel", "test-chat-id")
+
+	ctx := context.Background()
+	args := map[string]interface{}{} // content missing
+
+	result := tool.Execute(ctx, args)
+
+	// Verify error result for missing content
+	if !result.IsError {
+		t.Error("Expected IsError=true for missing content")
+	}
+	if result.ForLLM != "content is required" {
+		t.Errorf("Expected ForLLM 'content is required', got '%s'", result.ForLLM)
+	}
+}
+
+func TestMessageTool_Execute_NoTargetChannel(t *testing.T) {
+	tool := NewMessageTool()
+	// No SetContext called, so defaultChannel and defaultChatID are empty
+
+	tool.SetSendCallback(func(channel, chatID, content string) error {
+		return nil
+	})
+
+	ctx := context.Background()
+	args := map[string]interface{}{
+		"content": "Test message",
+	}
+
+	result := tool.Execute(ctx, args)
+
+	// Verify error when no target channel specified
+	if !result.IsError {
+		t.Error("Expected IsError=true when no target channel")
+	}
+	if result.ForLLM != "No target channel/chat specified" {
+		t.Errorf("Expected ForLLM 'No target channel/chat specified', got '%s'", result.ForLLM)
+	}
+}
+
+func TestMessageTool_Execute_NotConfigured(t *testing.T) {
+	tool := NewMessageTool()
+	tool.SetContext("test-channel", "test-chat-id")
+	// No SetSendCallback called
+
+	ctx := context.Background()
+	args := map[string]interface{}{
+		"content": "Test message",
+	}
+
+	result := tool.Execute(ctx, args)
+
+	// Verify error when send callback not configured
+	if !result.IsError {
+		t.Error("Expected IsError=true when send callback not configured")
+	}
+	if result.ForLLM != "Message sending not configured" {
+		t.Errorf("Expected ForLLM 'Message sending not configured', got '%s'", result.ForLLM)
+	}
+}
+
+func TestMessageTool_Name(t *testing.T) {
+	tool := NewMessageTool()
+	if tool.Name() != "message" {
+		t.Errorf("Expected name 'message', got '%s'", tool.Name())
+	}
+}
+
+func TestMessageTool_Description(t *testing.T) {
+	tool := NewMessageTool()
+	desc := tool.Description()
+	if desc == "" {
+		t.Error("Description should not be empty")
+	}
+}
+
+func TestMessageTool_Parameters(t *testing.T) {
+	tool := NewMessageTool()
+	params := tool.Parameters()
+
+	// Verify parameters structure
+	typ, ok := params["type"].(string)
+	if !ok || typ != "object" {
+		t.Error("Expected type 'object'")
+	}
+
+	props, ok := params["properties"].(map[string]interface{})
+	if !ok {
+		t.Fatal("Expected properties to be a map")
+	}
+
+	// Check required properties
+	required, ok := params["required"].([]string)
+	if !ok || len(required) != 1 || required[0] != "content" {
+		t.Error("Expected 'content' to be required")
+	}
+
+	// Check content property
+	contentProp, ok := props["content"].(map[string]interface{})
+	if !ok {
+		t.Error("Expected 'content' property")
+	}
+	if contentProp["type"] != "string" {
+		t.Error("Expected content type to be 'string'")
+	}
+
+	// Check channel property (optional)
+	channelProp, ok := props["channel"].(map[string]interface{})
+	if !ok {
+		t.Error("Expected 'channel' property")
+	}
+	if channelProp["type"] != "string" {
+		t.Error("Expected channel type to be 'string'")
+	}
+
+	// Check chat_id property (optional)
+	chatIDProp, ok := props["chat_id"].(map[string]interface{})
+	if !ok {
+		t.Error("Expected 'chat_id' property")
+	}
+	if chatIDProp["type"] != "string" {
+		t.Error("Expected chat_id type to be 'string'")
+	}
+}