fix: eliminate data races on shared tool instances (#1080)

* fix: eliminate data races on shared tool instances

Signed-off-by: Boris Bliznioukov <blib@mail.com>

* fix: remove unused indirect dependency on github.com/gdamore/tcell/v2

Signed-off-by: Boris Bliznioukov <blib@mail.com>

* fix: reviewer comments improve context handling for tool execution and ensure defaults for non-conversation callers

Signed-off-by: Boris Bliznioukov <blib@mail.com>

---------

Signed-off-by: Boris Bliznioukov <blib@mail.com>

pkg/tools/subagent.go

@@ -252,16 +252,12 @@ func (sm *SubagentManager) ListTasks() []*SubagentTask {
 // Unlike SpawnTool which runs tasks asynchronously, SubagentTool waits for completion
 // and returns the result directly in the ToolResult.
 type SubagentTool struct {
-	manager       *SubagentManager
-	originChannel string
-	originChatID  string
+	manager *SubagentManager
 }
 
 func NewSubagentTool(manager *SubagentManager) *SubagentTool {
 	return &SubagentTool{
-		manager:       manager,
-		originChannel: "cli",
-		originChatID:  "direct",
+		manager: manager,
 	}
 }
 
@@ -290,11 +286,6 @@ func (t *SubagentTool) Parameters() map[string]any {
 	}
 }
 
-func (t *SubagentTool) SetContext(channel, chatID string) {
-	t.originChannel = channel
-	t.originChatID = chatID
-}
-
 func (t *SubagentTool) Execute(ctx context.Context, args map[string]any) *ToolResult {
 	task, ok := args["task"].(string)
 	if !ok {
@@ -341,13 +332,24 @@ func (t *SubagentTool) Execute(ctx context.Context, args map[string]any) *ToolRe
 		}
 	}
 
+	// Fall back to "cli"/"direct" for non-conversation callers (e.g., CLI, tests)
+	// to preserve the same defaults as the original NewSubagentTool constructor.
+	channel := ToolChannel(ctx)
+	if channel == "" {
+		channel = "cli"
+	}
+	chatID := ToolChatID(ctx)
+	if chatID == "" {
+		chatID = "direct"
+	}
+
 	loopResult, err := RunToolLoop(ctx, ToolLoopConfig{
 		Provider:      sm.provider,
 		Model:         sm.defaultModel,
 		Tools:         tools,
 		MaxIterations: maxIter,
 		LLMOptions:    llmOptions,
-	}, messages, t.originChannel, t.originChatID)
+	}, messages, channel, chatID)
 	if err != nil {
 		return ErrorResult(fmt.Sprintf("Subagent execution failed: %v", err)).WithError(err)
 	}