refactor(agent): Pi 会话运行时 - 接入原生 Agent 与 Skills 工具链

backend/internal/app/cloud_agent_runtime_tool_result_test.go

@@ -0,0 +1,42 @@
+package app
+
+import (
+	"context"
+	"strings"
+	"testing"
+
+	"infinite-canvas/backend/internal/model"
+)
+
+// 线上复现：recall_lessons 经运行时工具桥执行后，交回模型的 tool 消息是 "null"，
+// 上游拿到空结果后返回空内容，整轮失败。任何工具结果都必须是非空的 JSON 文本。
+func TestCloudAgentRuntimeToolResultIsNeverNull(t *testing.T) {
+	s, db, _, _ := creationTestService(t)
+	if err := db.Create(&model.CanvasProject{ID: "agent-canvas", UserID: "user", PayloadJSON: `{"nodes":[]}`}).Error; err != nil {
+		t.Fatal(err)
+	}
+	run, err := s.CreateCloudAgentRun("user", agentTestRequest(), "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, tc := range []struct{ name, args string }{
+		{"recall_lessons", `{"topic":"用户称呼偏好"}`},
+		{"recall_lessons", `{}`},
+		{"canvas_list_node_types", `{}`},
+		{"canvas_get_state", `{}`},
+	} {
+		var call cloudAgentCall
+		call.ID = "call-" + tc.name + "-" + tc.args
+		call.Function.Name = tc.name
+		call.Function.Arguments = tc.args
+		result, err := s.executeCloudAgentRuntimeTool(context.Background(), "user", run.ID, call)
+		if err != nil {
+			t.Fatalf("%s(%s) bridge error: %v", tc.name, tc.args, err)
+		}
+		payload, _ := result.(map[string]any)
+		content, _ := payload["content"].(string)
+		if strings.TrimSpace(content) == "" || content == "null" {
+			t.Fatalf("%s(%s) returned empty tool content: %#v", tc.name, tc.args, result)
+		}
+	}
+}