diff --git a/internal/helpers/aitable.go b/internal/helpers/aitable.go
index cf465741..83ff658a 100644
--- a/internal/helpers/aitable.go
+++ b/internal/helpers/aitable.go
@@ -4150,6 +4150,10 @@ role-get 自行 merge）。
 			if err := validateRequiredFlags(cmd, "file-name"); err != nil {
 				return err
 			}
+			fileSize, _ := cmd.Flags().GetInt64("file-size")
+			if fileSize <= 0 {
+				return fmt.Errorf("flag --file-size is required and must be a positive integer")
+			}
 			baseID, err := mustFlagOrFallback(cmd, "base-id", "base")
 			if err != nil {
 				return err
@@ -4157,9 +4161,7 @@ role-get 自行 merge）。
 			toolArgs := map[string]any{
 				"baseId":   baseID,
 				"fileName": mustGetFlag(cmd, "file-name"),
-			}
-			if v, _ := cmd.Flags().GetInt64("file-size"); v > 0 {
-				toolArgs["fileSize"] = v
+				"fileSize": fileSize,
 			}
 			return callAitableTool("prepare_import_upload", toolArgs)
 		},
diff --git a/internal/helpers/aitable_import_upload_test.go b/internal/helpers/aitable_import_upload_test.go
new file mode 100644
index 00000000..13f400e8
--- /dev/null
+++ b/internal/helpers/aitable_import_upload_test.go
@@ -0,0 +1,82 @@
+// Copyright 2026 Alibaba Group
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+
+package helpers
+
+import (
+	"context"
+	"io"
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func runAitableImportUploadCommand(t *testing.T, args ...string) (*aitableTestCaller, error) {
+	t.Helper()
+	caller := &aitableTestCaller{}
+	installAitableDeps(t, caller)
+	deps.Out.w = io.Discard
+	deps.Out.errW = io.Discard
+
+	cmd := newAitableCommand()
+	cmd.SilenceErrors = true
+	cmd.SilenceUsage = true
+	cmd.SetOut(io.Discard)
+	cmd.SetErr(io.Discard)
+	cmd.SetArgs(append([]string{"import", "upload"}, args...))
+	return caller, cmd.ExecuteContext(context.Background())
+}
+
+func TestAitableImportUploadRequiresPositiveFileSize(t *testing.T) {
+	tests := []struct {
+		name string
+		args []string
+	}{
+		{name: "missing", args: nil},
+		{name: "zero", args: []string{"--file-size", "0"}},
+		{name: "negative", args: []string{"--file-size", "-1"}},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			args := []string{"--base-id", "base-smoke", "--file-name", "data.xlsx"}
+			caller, err := runAitableImportUploadCommand(t, append(args, test.args...)...)
+			if err == nil {
+				t.Fatal("expected --file-size validation error")
+			}
+			if !strings.Contains(err.Error(), "--file-size") {
+				t.Fatalf("error = %q, want --file-size validation", err)
+			}
+			if len(caller.calls) != 0 {
+				t.Fatalf("invalid file size dispatched %d MCP call(s): %#v", len(caller.calls), caller.calls)
+			}
+		})
+	}
+}
+
+func TestAitableImportUploadPassesFileSizeToMCP(t *testing.T) {
+	caller, err := runAitableImportUploadCommand(t,
+		"--base-id", "base-smoke",
+		"--file-name", "data.xlsx",
+		"--file-size", "204800",
+	)
+	if err != nil {
+		t.Fatalf("aitable import upload returned error: %v", err)
+	}
+	if len(caller.calls) != 1 {
+		t.Fatalf("tool call count = %d, want 1", len(caller.calls))
+	}
+	call := caller.calls[0]
+	if call.server != "aitable" || call.tool != "prepare_import_upload" {
+		t.Fatalf("tool call = %s/%s, want aitable/prepare_import_upload", call.server, call.tool)
+	}
+	want := map[string]any{
+		"baseId":   "base-smoke",
+		"fileName": "data.xlsx",
+		"fileSize": int64(204800),
+	}
+	if !reflect.DeepEqual(call.args, want) {
+		t.Fatalf("tool args = %#v, want %#v", call.args, want)
+	}
+}
diff --git a/internal/shortcut/aitable/aitable.go b/internal/shortcut/aitable/aitable.go
index 1ce20aab..14a7418b 100644
--- a/internal/shortcut/aitable/aitable.go
+++ b/internal/shortcut/aitable/aitable.go
@@ -2107,16 +2107,27 @@ var ImportUpload = shortcut.Shortcut{
 	Flags: []shortcut.Flag{
 		{Name: "base-id", Type: shortcut.FlagString, Desc: "Base ID", Required: true},
 		{Name: "file-name", Type: shortcut.FlagString, Desc: "文件名（含扩展名）", Required: true},
-		{Name: "file-size", Type: shortcut.FlagInt, Desc: "文件大小（字节，可选）"},
+		{Name: "file-size", Type: shortcut.FlagInt, Desc: "文件大小（字节，必须大于 0）", Required: true},
+	},
+	Constraints: []shortcut.Constraint{
+		{
+			Kind:        shortcut.ConstraintCustom,
+			Flags:       []string{"file-size"},
+			Description: "--file-size 必须是大于 0 的整数（实际文件大小，单位字节）",
+		},
 	},
 	Tips: []string{`dws aitable +import-upload --base-id B --file-name data.xlsx --file-size 204800`},
+	Validate: func(rt *shortcut.RuntimeContext) error {
+		if rt.Int("file-size") <= 0 {
+			return fmt.Errorf("flag --file-size is required and must be a positive integer")
+		}
+		return nil
+	},
 	Execute: func(rt *shortcut.RuntimeContext) error {
 		params := map[string]any{
 			"baseId":   rt.Str("base-id"),
 			"fileName": rt.Str("file-name"),
-		}
-		if rt.Changed("file-size") {
-			params["fileSize"] = rt.Int("file-size")
+			"fileSize": rt.Int("file-size"),
 		}
 		return rt.CallMCP("prepare_import_upload", params)
 	},
diff --git a/internal/shortcut/aitable/compatibility_coverage_test.go b/internal/shortcut/aitable/compatibility_coverage_test.go
new file mode 100644
index 00000000..458d95f1
--- /dev/null
+++ b/internal/shortcut/aitable/compatibility_coverage_test.go
@@ -0,0 +1,117 @@
+// Copyright 2026 Alibaba Group
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package aitable
+
+import (
+	"context"
+	"io"
+	"strings"
+	"testing"
+
+	"github.com/DingTalk-Real-AI/dingtalk-workspace-cli/internal/helpers"
+	"github.com/DingTalk-Real-AI/dingtalk-workspace-cli/internal/shortcut"
+	"github.com/DingTalk-Real-AI/dingtalk-workspace-cli/pkg/edition"
+	"github.com/spf13/cobra"
+)
+
+type platformCoverageCaller struct {
+	called  bool
+	product string
+	tool    string
+	args    map[string]any
+}
+
+func (f *platformCoverageCaller) reset() {
+	f.called, f.product, f.tool, f.args = false, "", "", nil
+}
+
+func (f *platformCoverageCaller) CallTool(_ context.Context, product, tool string, args map[string]any) (*edition.ToolResult, error) {
+	f.called, f.product, f.tool, f.args = true, product, tool, args
+	return &edition.ToolResult{
+		Content: []edition.ContentBlock{{Type: "text", Text: `{"result":[]}`}},
+	}, nil
+}
+
+func (f *platformCoverageCaller) Format() string { return "json" }
+func (f *platformCoverageCaller) DryRun() bool   { return false }
+func (f *platformCoverageCaller) Fields() string { return "" }
+func (f *platformCoverageCaller) JQ() string     { return "" }
+
+func newPlatformCoverageRoot() *cobra.Command {
+	root := &cobra.Command{Use: "dws", SilenceUsage: true, SilenceErrors: true}
+	root.SetOut(io.Discard)
+	root.SetErr(io.Discard)
+	root.PersistentFlags().Bool("yes", false, "")
+	root.PersistentFlags().Bool("dry-run", false, "")
+	root.PersistentFlags().String("format", "json", "")
+	root.AddCommand(shortcut.Commands()...)
+	return root
+}
+
+func TestCrossPlatformCoverageImportUploadRequiresPositiveFileSize(t *testing.T) {
+	fake := &platformCoverageCaller{}
+	helpers.InitDeps(fake)
+
+	tests := []struct {
+		name     string
+		fileSize string
+		wantErr  bool
+	}{
+		{name: "missing", wantErr: true},
+		{name: "zero", fileSize: "0", wantErr: true},
+		{name: "negative", fileSize: "-1", wantErr: true},
+		{name: "positive", fileSize: "204800"},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			fake.reset()
+			root := newPlatformCoverageRoot()
+			args := []string{
+				"aitable", "+import-upload",
+				"--base-id", "base-smoke",
+				"--file-name", "data.xlsx",
+				"--yes",
+			}
+			if test.fileSize != "" {
+				args = append(args, "--file-size", test.fileSize)
+			}
+			root.SetArgs(args)
+			err := root.Execute()
+
+			if test.wantErr {
+				if err == nil {
+					t.Fatal("expected --file-size validation error")
+				}
+				if !strings.Contains(err.Error(), "--file-size") {
+					t.Fatalf("error = %q, want --file-size validation", err)
+				}
+				if fake.called {
+					t.Fatalf("invalid file size called %s/%s with %#v", fake.product, fake.tool, fake.args)
+				}
+				return
+			}
+
+			if err != nil {
+				t.Fatalf("positive file size returned error: %v", err)
+			}
+			if !fake.called || fake.product != "aitable" || fake.tool != "prepare_import_upload" {
+				t.Fatalf("tool call = called:%v %s/%s, want aitable/prepare_import_upload", fake.called, fake.product, fake.tool)
+			}
+			if got := fake.args["fileSize"]; got != 204800 {
+				t.Fatalf("fileSize = %#v, want 204800", got)
+			}
+		})
+	}
+}