diff --git a/admin/handler/web/inner_code.go b/admin/handler/web/inner_code.go
index 5e20c83..a969f72 100644
--- a/admin/handler/web/inner_code.go
+++ b/admin/handler/web/inner_code.go
@@ -155,6 +155,70 @@ func (h *Handler) InnerCodeMatch(c *gin.Context) {
 	h.innerCodeRedirect(c, businessDate, status, keyword, pageNumber, message)
 }
 
+// InnerCodeApply 在操作员确认后逐条执行安全回写。
+func (h *Handler) InnerCodeApply(c *gin.Context) {
+	businessDate, status, keyword := c.PostForm("date"), c.PostForm("status"), c.PostForm("q")
+	pageNumber := service.ParsePage(c.PostForm("page"))
+	ids := make([]int64, 0)
+	for _, raw := range c.PostFormArray("ids") {
+		if id, err := strconv.ParseInt(strings.TrimSpace(raw), 10, 64); err == nil && id > 0 {
+			ids = append(ids, id)
+		}
+	}
+	client, message := h.innerCodeSybClient()
+	if message != "" {
+		h.innerCodeRedirect(c, businessDate, status, keyword, pageNumber, message)
+		return
+	}
+	result, err := service.ApplyInnerCodes(c.Request.Context(), h.db, client, ids, currentUser(c).UserID)
+	if err != nil {
+		h.innerCodeRedirect(c, businessDate, status, keyword, pageNumber, "回写未完成："+err.Error())
+		return
+	}
+	message = fmt.Sprintf("回写完成：选择 %d 条，成功 %d 条，已存在 %d 条，跳过 %d 条，失败 %d 条，需核对 %d 条。",
+		result.Requested, result.Updated, result.AlreadyFilled, result.Skipped, result.Failed, result.NeedsCheck)
+	h.innerCodeRedirect(c, businessDate, status, keyword, pageNumber, message)
+}
+
+// InnerCodeRecheck 只重新读取未知结果，绝不再次发送删除或写入。
+func (h *Handler) InnerCodeRecheck(c *gin.Context) {
+	businessDate, status, keyword := c.PostForm("date"), c.PostForm("status"), c.PostForm("q")
+	pageNumber := service.ParsePage(c.PostForm("page"))
+	id, err := strconv.ParseInt(strings.TrimSpace(c.PostForm("id")), 10, 64)
+	if err != nil || id <= 0 {
+		h.innerCodeRedirect(c, businessDate, status, keyword, pageNumber, "记录编号无效，没有执行核对。")
+		return
+	}
+	client, message := h.innerCodeSybClient()
+	if message != "" {
+		h.innerCodeRedirect(c, businessDate, status, keyword, pageNumber, message)
+		return
+	}
+	_, message, err = service.RecheckInnerCode(c.Request.Context(), h.db, client, id)
+	if err != nil {
+		message = "重新核对失败：" + err.Error()
+	}
+	h.innerCodeRedirect(c, businessDate, status, keyword, pageNumber, message)
+}
+
+func (h *Handler) innerCodeSybClient() (*syb.Client, string) {
+	cfg, err := config.Load()
+	if err != nil {
+		return nil, "顺运宝配置不可用，没有发送远端请求。"
+	}
+	client, err := syb.New(cfg.Syb.BaseURL)
+	if err != nil {
+		return nil, "顺运宝地址配置有误，没有发送远端请求。"
+	}
+	if err := service.EnsureSybSession(h.db, client, cfg.Syb.Username, time.Now()); err != nil {
+		if errors.Is(err, service.ErrSybLoginRequired) {
+			return nil, "顺运宝会话已过期，请先到“顺运宝数据”页面登录。"
+		}
+		return nil, "校验顺运宝会话失败，没有发送远端请求。"
+	}
+	return client, ""
+}
+
 func (h *Handler) innerCodeRedirect(c *gin.Context, businessDate, status, keyword string, pageNumber int, message string) {
 	values := url.Values{"date": {businessDate}, "page": {strconv.Itoa(pageNumber)}, "message": {message}}
 	if strings.TrimSpace(status) != "" {
diff --git a/admin/handler/web/web.go b/admin/handler/web/web.go
index fc32646..e2710af 100644
--- a/admin/handler/web/web.go
+++ b/admin/handler/web/web.go
@@ -120,6 +120,8 @@ func Register(r *gin.Engine, db *sql.DB, onlineThreshold time.Duration, aiSecret
 	innerCodes := pages.Group("/inner-codes")
 	innerCodes.POST("/import", h.InnerCodeImport)
 	innerCodes.POST("/match", h.InnerCodeMatch)
+	innerCodes.POST("/apply", h.InnerCodeApply)
+	innerCodes.POST("/recheck", h.InnerCodeRecheck)
 
 	// 7. 用户管理：先经过网页登录，再叠加管理员角色校验。
 	users := pages.Group("/users", AdminRequired())
diff --git a/admin/main.go b/admin/main.go
index 8ca9f9e..e9d2c0f 100644
--- a/admin/main.go
+++ b/admin/main.go
@@ -78,6 +78,13 @@ func main() {
 	if aiInterrupted > 0 {
 		log.Printf("已把 %d 个上次进程遗留的 AI 匹配批次标记为中断", aiInterrupted)
 	}
+	innerCodeInterrupted, err := service.InterruptApplyingInnerCodes(db, time.Now())
+	if err != nil {
+		log.Fatalf("恢复中断的档口入库码回写失败: %v", err)
+	}
+	if innerCodeInterrupted > 0 {
+		log.Printf("已把 %d 条上次进程遗留的档口入库码回写标记为需核对", innerCodeInterrupted)
+	}
 	log.Printf("数据库已就绪")
 
 	// 3. Web 引擎
diff --git a/admin/repository/inner_code.go b/admin/repository/inner_code.go
index 2cf81e7..ab9850a 100644
--- a/admin/repository/inner_code.go
+++ b/admin/repository/inner_code.go
@@ -274,6 +274,102 @@ func scanInnerCodeRecord(scanner innerCodeRowScanner) (model.InnerCodeRecord, er
 	return row, nil
 }
 
+// ClaimInnerCodeForApply 原子领取一条 ready 记录。返回 claimed=false 表示状态已变化。
+func ClaimInnerCodeForApply(db *sql.DB, id int64, actorUserID, now string) (*model.InnerCodeRecord, bool, error) {
+	tx, err := db.Begin()
+	if err != nil {
+		return nil, false, fmt.Errorf("开始领取档口入库码事务失败: %w", err)
+	}
+	defer tx.Rollback()
+	record, err := scanInnerCodeRecord(tx.QueryRow(`SELECT `+innerCodeListColumns+
+		` FROM syb_inner_code_records WHERE id=? FOR UPDATE`, id))
+	if errors.Is(err, sql.ErrNoRows) {
+		return nil, false, nil
+	}
+	if err != nil {
+		return nil, false, err
+	}
+	if record.Status != model.InnerCodeReady {
+		return &record, false, nil
+	}
+	result, err := tx.Exec(`UPDATE syb_inner_code_records
+		SET status='applying',applied_by_user_id=?,apply_started_at=?,updated_at=?
+		WHERE id=? AND status='ready'`, actorUserID, now, now, id)
+	if err != nil {
+		return nil, false, fmt.Errorf("领取档口入库码记录失败: %w", err)
+	}
+	if affected, err := result.RowsAffected(); err != nil || affected != 1 {
+		return &record, false, nil
+	}
+	if err := tx.Commit(); err != nil {
+		return nil, false, fmt.Errorf("提交档口入库码领取失败: %w", err)
+	}
+	record.Status = model.InnerCodeApplying
+	record.AppliedByUserID = actorUserID
+	record.ApplyStartedAt = now
+	record.UpdatedAt = now
+	return &record, true, nil
+}
+
+// FinishInnerCodeApply 保存一条已领取记录的最终结果。
+func FinishInnerCodeApply(q Execer, id int64, status model.InnerCodeStatus, message, remoteCode, finishedAt string) error {
+	result, err := q.Exec(`UPDATE syb_inner_code_records
+		SET status=?,result_message=?,remote_inner_code=?,
+		    applied_at=CASE WHEN ? IN ('updated','already_filled') THEN ? ELSE applied_at END,
+		    updated_at=?
+		WHERE id=? AND status='applying'`, status, message, nullableString(remoteCode), status, finishedAt, finishedAt, id)
+	if err != nil {
+		return fmt.Errorf("保存档口入库码回写结果失败: %w", err)
+	}
+	if affected, err := result.RowsAffected(); err != nil || affected != 1 {
+		return fmt.Errorf("档口入库码记录 %d 已不在回写中，拒绝覆盖结果", id)
+	}
+	return nil
+}
+
+// GetInnerCodeForRecheck 读取一条需核对记录。
+func GetInnerCodeForRecheck(q Execer, id int64) (*model.InnerCodeRecord, error) {
+	record, err := scanInnerCodeRecord(q.QueryRow(`SELECT `+innerCodeListColumns+
+		` FROM syb_inner_code_records WHERE id=?`, id))
+	if errors.Is(err, sql.ErrNoRows) {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &record, nil
+}
+
+// SaveInnerCodeRecheck 保存只读重新核对的远端结果，不执行状态领取或写入。
+func SaveInnerCodeRecheck(q Execer, id int64, status model.InnerCodeStatus, message, remoteCode, checkedAt string) error {
+	result, err := q.Exec(`UPDATE syb_inner_code_records
+		SET status=?,result_message=?,remote_inner_code=?,
+		    applied_at=CASE WHEN ?='updated' THEN ? ELSE applied_at END,updated_at=?
+		WHERE id=? AND status='needs_check'`, status, message, nullableString(remoteCode), status, checkedAt, checkedAt, id)
+	if err != nil {
+		return fmt.Errorf("保存档口入库码核对结果失败: %w", err)
+	}
+	if affected, err := result.RowsAffected(); err != nil || affected != 1 {
+		return fmt.Errorf("档口入库码记录 %d 已不需要核对", id)
+	}
+	return nil
+}
+
+// InterruptApplyingInnerCodes 在启动时把未知结果的 applying 收敛为 needs_check。
+func InterruptApplyingInnerCodes(q Execer, interruptedAt string) (int, error) {
+	result, err := q.Exec(`UPDATE syb_inner_code_records
+		SET status='needs_check',result_message='Admin 在回写完成前退出，请重新核对远端结果；系统不会自动重写',
+		    updated_at=? WHERE status='applying'`, interruptedAt)
+	if err != nil {
+		return 0, fmt.Errorf("恢复中断的档口入库码回写失败: %w", err)
+	}
+	affected, err := result.RowsAffected()
+	if err != nil {
+		return 0, fmt.Errorf("读取中断档口入库码数量失败: %w", err)
+	}
+	return int(affected), nil
+}
+
 func nullablePositiveInt(value int) any {
 	if value <= 0 {
 		return nil
diff --git a/admin/repository/inner_code_test.go b/admin/repository/inner_code_test.go
new file mode 100644
index 0000000..58663be
--- /dev/null
+++ b/admin/repository/inner_code_test.go
@@ -0,0 +1,40 @@
+package repository
+
+import (
+	"database/sql"
+	"testing"
+
+	_ "modernc.org/sqlite"
+)
+
+func TestInterruptApplyingInnerCodes_只收敛回写中记录(t *testing.T) {
+	db, err := sql.Open("sqlite", "file:inner_code_interrupt?mode=memory&cache=shared")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+	if _, err := db.Exec(`CREATE TABLE syb_inner_code_records (
+		id INTEGER PRIMARY KEY,status TEXT NOT NULL,result_message TEXT,updated_at TEXT NOT NULL
+	)`); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := db.Exec(`INSERT INTO syb_inner_code_records(id,status,updated_at) VALUES
+		(1,'applying','old'),(2,'ready','old')`); err != nil {
+		t.Fatal(err)
+	}
+	count, err := InterruptApplyingInnerCodes(db, "2026-08-15T01:00:00Z")
+	if err != nil || count != 1 {
+		t.Fatalf("count=%d err=%v", count, err)
+	}
+	var status, message, updatedAt string
+	if err := db.QueryRow(`SELECT status,result_message,updated_at FROM syb_inner_code_records WHERE id=1`).
+		Scan(&status, &message, &updatedAt); err != nil {
+		t.Fatal(err)
+	}
+	if status != "needs_check" || message == "" || updatedAt != "2026-08-15T01:00:00Z" {
+		t.Fatalf("status=%s message=%q updated=%s", status, message, updatedAt)
+	}
+	if err := db.QueryRow(`SELECT status FROM syb_inner_code_records WHERE id=2`).Scan(&status); err != nil || status != "ready" {
+		t.Fatalf("ready 记录不应变化 status=%s err=%v", status, err)
+	}
+}
diff --git a/admin/repository/mysql_db_integration_test.go b/admin/repository/mysql_db_integration_test.go
index f7155d8..3705302 100644
--- a/admin/repository/mysql_db_integration_test.go
+++ b/admin/repository/mysql_db_integration_test.go
@@ -1083,6 +1083,40 @@ func prepareMySQLV8(t *testing.T, db *sql.DB) {
 	mustExec(t, db, `INSERT INTO schema_migrations(version,applied_at) VALUES(8,'2026-08-11T00:00:00Z')`)
 }
 
+func TestMySQLMigrate_V22升级V23且唯一约束生效(t *testing.T) {
+	db := openMySQLMigrationTestDB(t)
+	defer db.Close()
+	cleanMySQLTestSchema(t, db)
+	defer cleanMySQLTestSchema(t, db)
+	if err := MigrateMySQL(db); err != nil {
+		t.Fatal(err)
+	}
+	mustExec(t, db, `SET FOREIGN_KEY_CHECKS=0`)
+	mustExec(t, db, `DROP TABLE syb_inner_code_records`)
+	mustExec(t, db, `DELETE FROM schema_migrations WHERE version=23`)
+	mustExec(t, db, `SET FOREIGN_KEY_CHECKS=1`)
+	if err := MigrateMySQL(db); err != nil {
+		t.Fatalf("v22 升级 v23 失败: %v", err)
+	}
+	if err := MigrateMySQL(db); err != nil {
+		t.Fatalf("v23 重复迁移失败: %v", err)
+	}
+	if err := checkMySQLV23Shape(db); err != nil {
+		t.Fatal(err)
+	}
+	now := "2026-08-15T00:00:00Z"
+	mustExec(t, db, `INSERT INTO users(user_id,username,password_hash,role,status,password_changed_at,created_at,updated_at)
+		VALUES('inner-user','inner-user','hash','purchaser','active',?,?,?)`, now, now, now)
+	mustExec(t, db, `INSERT INTO syb_inner_code_records
+		(business_date,source_row,order_number,stall,spec_raw,spec_key,inner_code,status,created_by_user_id,created_at,updated_at)
+		VALUES('2026-08-15',2,'ORDER-1','A#1','黑色,M','黑色,M','DK-1','pending','inner-user',?,?)`, now, now)
+	if _, err := db.Exec(`INSERT INTO syb_inner_code_records
+		(business_date,source_row,order_number,stall,spec_raw,spec_key,inner_code,status,created_by_user_id,created_at,updated_at)
+		VALUES('2026-08-15',3,'ORDER-2','B#2','白色,L','白色,L','DK-1','pending','inner-user',?,?)`, now, now); err == nil {
+		t.Fatal("同一业务日期的 inner_code 唯一约束必须拒绝冲突")
+	}
+}
+
 func mustExec(t *testing.T, db *sql.DB, query string, args ...any) {
 	t.Helper()
 	if _, err := db.Exec(query, args...); err != nil {
diff --git a/admin/service/inner_code_apply.go b/admin/service/inner_code_apply.go
new file mode 100644
index 0000000..0958b15
--- /dev/null
+++ b/admin/service/inner_code_apply.go
@@ -0,0 +1,243 @@
+package service
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"cmautobuy/admin/model"
+	"cmautobuy/admin/repository"
+	"cmautobuy/admin/syb"
+)
+
+// InnerCodeWriter 是安全回写所需的最小顺运宝接口。
+type InnerCodeWriter interface {
+	InnerCodeDetailReader
+	DeleteInnerCode(context.Context, int64) error
+	UpdateDetailCode(context.Context, int64, int64, string) error
+}
+
+// InnerCodeApplyResult 是一次用户确认操作的统计。
+type InnerCodeApplyResult struct {
+	Requested     int
+	Updated       int
+	AlreadyFilled int
+	Skipped       int
+	Failed        int
+	NeedsCheck    int
+}
+
+type innerCodeApplyOutcome struct {
+	Status     model.InnerCodeStatus
+	Message    string
+	RemoteCode string
+}
+
+// ApplyInnerCodes 逐条原子领取并回写。每条写请求只发送一次，单条失败不阻断后续行。
+func ApplyInnerCodes(ctx context.Context, db *sql.DB, writer InnerCodeWriter, ids []int64, actorUserID string) (*InnerCodeApplyResult, error) {
+	ids = uniquePositiveInnerCodeIDs(ids)
+	if len(ids) == 0 {
+		return nil, fmt.Errorf("没有选择可回写记录")
+	}
+	if len(ids) > PageSize {
+		return nil, fmt.Errorf("单次最多回写当前页 %d 条记录", PageSize)
+	}
+	result := &InnerCodeApplyResult{Requested: len(ids)}
+	for _, id := range ids {
+		now := model.NowISO()
+		record, claimed, err := repository.ClaimInnerCodeForApply(db, id, actorUserID, now)
+		if err != nil {
+			return nil, err
+		}
+		if !claimed {
+			result.Skipped++
+			continue
+		}
+		outcome := applyClaimedInnerCode(ctx, writer, *record)
+		finishedAt := model.NowISO()
+		if err := repository.FinishInnerCodeApply(db, id, outcome.Status, compactInnerCodeMessage(outcome.Message), outcome.RemoteCode, finishedAt); err != nil {
+			return nil, err
+		}
+		switch outcome.Status {
+		case model.InnerCodeUpdated:
+			result.Updated++
+		case model.InnerCodeAlreadyFilled:
+			result.AlreadyFilled++
+		case model.InnerCodeNeedsCheck:
+			result.NeedsCheck++
+		case model.InnerCodeFailed:
+			result.Failed++
+		default:
+			result.Skipped++
+		}
+	}
+	return result, nil
+}
+
+func applyClaimedInnerCode(ctx context.Context, writer InnerCodeWriter, record model.InnerCodeRecord) innerCodeApplyOutcome {
+	item, err := readCurrentInnerCodeDetail(ctx, writer, record)
+	if err != nil {
+		return innerCodeApplyOutcome{Status: model.InnerCodeNeedsCheck,
+			Message: "写入前重新读取失败，没有发送删除或写入请求：" + err.Error(), RemoteCode: record.RemoteInnerCode}
+	}
+	currentCode := innerCodeRawText(item.Raw["innerExpCode"])
+	if !innerCodeDetailIdentityMatches(record, *item) {
+		return innerCodeApplyOutcome{Status: model.InnerCodeSkipped,
+			Message: "顺运宝商品规格或档口身份已变化，停止回写，请重新匹配", RemoteCode: currentCode}
+	}
+	platform := innerCodeRawText(item.Raw["purchasePlatform"])
+	purchaseCode := innerCodeRawText(item.Raw["purchaseCode"])
+	if platform != "" || purchaseCode != "" {
+		return innerCodeApplyOutcome{Status: model.InnerCodeSkipped,
+			Message: "顺运宝商品已有采购平台或采购单号，停止回写", RemoteCode: currentCode}
+	}
+	if currentCode == record.InnerCode {
+		return innerCodeApplyOutcome{Status: model.InnerCodeAlreadyFilled,
+			Message: "写入前核验发现远端已是目标入库码，无需重复写入", RemoteCode: currentCode}
+	}
+	if currentCode != record.RemoteInnerCode {
+		return innerCodeApplyOutcome{Status: model.InnerCodeNeedsCheck,
+			Message: "远端快递单号在规划后发生变化，已停止回写，请人工核对", RemoteCode: currentCode}
+	}
+	if currentCode != "" {
+		if err := writer.DeleteInnerCode(ctx, record.DetailID); err != nil {
+			status := model.InnerCodeFailed
+			message := "删除旧快递单号失败，未发送新值写入请求：" + err.Error()
+			if errors.Is(err, syb.ErrWriteResultUnknown) {
+				status = model.InnerCodeNeedsCheck
+				message = "删除旧快递单号的结果未知，禁止自动继续写入，请重新核对"
+			}
+			return innerCodeApplyOutcome{Status: status, Message: message, RemoteCode: currentCode}
+		}
+		currentCode = ""
+	}
+	if err := writer.UpdateDetailCode(ctx, record.StockID, record.DetailID, record.InnerCode); err != nil {
+		status := model.InnerCodeFailed
+		message := "写入档口入库码失败，系统不会自动重试：" + err.Error()
+		if errors.Is(err, syb.ErrWriteResultUnknown) {
+			status = model.InnerCodeNeedsCheck
+			message = "写入结果未知，禁止自动重试，请重新核对"
+		}
+		return innerCodeApplyOutcome{Status: status, Message: message, RemoteCode: currentCode}
+	}
+	verified, err := readCurrentInnerCodeDetail(ctx, writer, record)
+	if err != nil {
+		return innerCodeApplyOutcome{Status: model.InnerCodeNeedsCheck,
+			Message: "写入请求已成功响应，但重新读取失败，请核对远端结果", RemoteCode: currentCode}
+	}
+	verifiedCode := innerCodeRawText(verified.Raw["innerExpCode"])
+	if !innerCodeDetailIdentityMatches(record, *verified) {
+		return innerCodeApplyOutcome{Status: model.InnerCodeNeedsCheck,
+			Message: "写入后商品规格或档口身份发生变化，请人工核对", RemoteCode: verifiedCode}
+	}
+	if verifiedCode != record.InnerCode {
+		return innerCodeApplyOutcome{Status: model.InnerCodeNeedsCheck,
+			Message: "写入后远端值与目标入库码不一致，禁止自动重试，请人工核对", RemoteCode: verifiedCode}
+	}
+	return innerCodeApplyOutcome{Status: model.InnerCodeUpdated,
+		Message: "回写完成，远端再次读取结果一致", RemoteCode: verifiedCode}
+}
+
+func readCurrentInnerCodeDetail(ctx context.Context, reader InnerCodeDetailReader, record model.InnerCodeRecord) (*syb.DetailItem, error) {
+	if record.StockID <= 0 || record.DetailID <= 0 {
+		return nil, fmt.Errorf("记录缺少有效的货运单或商品明细 ID")
+	}
+	stocks, err := reader.DetailListByStock(ctx, []int64{record.StockID})
+	if err != nil {
+		return nil, err
+	}
+	if len(stocks) != 1 || stocks[0].ID != record.StockID {
+		return nil, fmt.Errorf("顺运宝没有唯一返回货运单 id=%d", record.StockID)
+	}
+	var found *syb.DetailItem
+	for index := range stocks[0].Details {
+		if stocks[0].Details[index].ID != record.DetailID {
+			continue
+		}
+		if found != nil {
+			return nil, fmt.Errorf("顺运宝重复返回商品明细 id=%d", record.DetailID)
+		}
+		item := stocks[0].Details[index]
+		found = &item
+	}
+	if found == nil {
+		return nil, fmt.Errorf("顺运宝未返回商品明细 id=%d", record.DetailID)
+	}
+	return found, nil
+}
+
+// RecheckInnerCode 只重新读取一条 needs_check 记录，不发送任何写请求。
+func RecheckInnerCode(ctx context.Context, db *sql.DB, reader InnerCodeDetailReader, id int64) (model.InnerCodeStatus, string, error) {
+	record, err := repository.GetInnerCodeForRecheck(db, id)
+	if err != nil {
+		return "", "", err
+	}
+	if record == nil {
+		return "", "", fmt.Errorf("档口入库码记录不存在")
+	}
+	if record.Status != model.InnerCodeNeedsCheck {
+		return record.Status, "当前记录不需要核对", nil
+	}
+	item, readErr := readCurrentInnerCodeDetail(ctx, reader, *record)
+	status := model.InnerCodeNeedsCheck
+	remoteCode := record.RemoteInnerCode
+	message := "重新读取失败，仍需人工核对：" + errorText(readErr)
+	if readErr == nil {
+		remoteCode = innerCodeRawText(item.Raw["innerExpCode"])
+		if !innerCodeDetailIdentityMatches(*record, *item) {
+			message = "重新读取到的商品身份与规划不一致；保持需核对，系统没有写入"
+		} else if remoteCode == record.InnerCode {
+			status = model.InnerCodeUpdated
+			message = "重新读取确认远端已是目标入库码；没有重复写入"
+		} else {
+			message = "重新读取后远端仍不是目标入库码；保持需核对，系统没有写入"
+		}
+	}
+	checkedAt := model.NowISO()
+	message = compactInnerCodeMessage(message)
+	if err := repository.SaveInnerCodeRecheck(db, id, status, message, remoteCode, checkedAt); err != nil {
+		return "", "", err
+	}
+	return status, message, nil
+}
+
+func innerCodeDetailIdentityMatches(record model.InnerCodeRecord, item syb.DetailItem) bool {
+	return item.ProductSpec == record.SybSpec &&
+		innerCodeRawText(item.Raw["sku"]) == record.SybSKU &&
+		innerCodeRawText(item.Raw["variationSku"]) == record.SybVariationSKU
+}
+
+func errorText(err error) string {
+	if err == nil {
+		return ""
+	}
+	return err.Error()
+}
+
+func uniquePositiveInnerCodeIDs(ids []int64) []int64 {
+	seen := make(map[int64]bool, len(ids))
+	result := make([]int64, 0, len(ids))
+	for _, id := range ids {
+		if id > 0 && !seen[id] {
+			seen[id] = true
+			result = append(result, id)
+		}
+	}
+	return result
+}
+
+// InterruptApplyingInnerCodes 在 Admin 启动时收敛未确认的远端写结果。
+func InterruptApplyingInnerCodes(db *sql.DB, now time.Time) (int, error) {
+	return repository.InterruptApplyingInnerCodes(db, now.UTC().Format(model.TimeLayout))
+}
+
+func compactInnerCodeMessage(message string) string {
+	message = strings.TrimSpace(message)
+	if len([]rune(message)) <= 500 {
+		return message
+	}
+	return string([]rune(message)[:500])
+}
diff --git a/admin/service/inner_code_apply_test.go b/admin/service/inner_code_apply_test.go
new file mode 100644
index 0000000..aeea10e
--- /dev/null
+++ b/admin/service/inner_code_apply_test.go
@@ -0,0 +1,139 @@
+package service
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"cmautobuy/admin/model"
+	"cmautobuy/admin/syb"
+)
+
+type fakeInnerCodeWriter struct {
+	stock       syb.StockDetail
+	readErr     error
+	deleteErr   error
+	updateErr   error
+	readCount   int
+	deleteCount int
+	updateCount int
+}
+
+func (f *fakeInnerCodeWriter) DetailListByStock(context.Context, []int64) ([]syb.StockDetail, error) {
+	f.readCount++
+	if f.readErr != nil {
+		return nil, f.readErr
+	}
+	return []syb.StockDetail{f.stock}, nil
+}
+
+func (f *fakeInnerCodeWriter) DeleteInnerCode(_ context.Context, detailID int64) error {
+	f.deleteCount++
+	if f.deleteErr != nil {
+		return f.deleteErr
+	}
+	for index := range f.stock.Details {
+		if f.stock.Details[index].ID == detailID {
+			f.stock.Details[index].Raw["innerExpCode"] = ""
+		}
+	}
+	return nil
+}
+
+func (f *fakeInnerCodeWriter) UpdateDetailCode(_ context.Context, _, detailID int64, code string) error {
+	f.updateCount++
+	if f.updateErr != nil {
+		return f.updateErr
+	}
+	for index := range f.stock.Details {
+		if f.stock.Details[index].ID == detailID {
+			f.stock.Details[index].Raw["innerExpCode"] = code
+		}
+	}
+	return nil
+}
+
+func TestApplyClaimedInnerCode_空旧值直接写并复读确认(t *testing.T) {
+	record := innerCodeApplyTestRecord("")
+	writer := innerCodeApplyTestWriter(record, "")
+	outcome := applyClaimedInnerCode(context.Background(), writer, record)
+	if outcome.Status != model.InnerCodeUpdated || writer.deleteCount != 0 || writer.updateCount != 1 || writer.readCount != 2 {
+		t.Fatalf("outcome=%+v counts read=%d delete=%d update=%d", outcome, writer.readCount, writer.deleteCount, writer.updateCount)
+	}
+}
+
+func TestApplyClaimedInnerCode_有旧值先删后写(t *testing.T) {
+	record := innerCodeApplyTestRecord("OLD")
+	writer := innerCodeApplyTestWriter(record, "OLD")
+	outcome := applyClaimedInnerCode(context.Background(), writer, record)
+	if outcome.Status != model.InnerCodeUpdated || writer.deleteCount != 1 || writer.updateCount != 1 {
+		t.Fatalf("outcome=%+v delete=%d update=%d", outcome, writer.deleteCount, writer.updateCount)
+	}
+}
+
+func TestApplyClaimedInnerCode_规划后远端值变化不写入(t *testing.T) {
+	record := innerCodeApplyTestRecord("OLD")
+	writer := innerCodeApplyTestWriter(record, "OTHER")
+	outcome := applyClaimedInnerCode(context.Background(), writer, record)
+	if outcome.Status != model.InnerCodeNeedsCheck || writer.deleteCount != 0 || writer.updateCount != 0 {
+		t.Fatalf("outcome=%+v delete=%d update=%d", outcome, writer.deleteCount, writer.updateCount)
+	}
+}
+
+func TestApplyClaimedInnerCode_删除明确失败不继续写(t *testing.T) {
+	record := innerCodeApplyTestRecord("OLD")
+	writer := innerCodeApplyTestWriter(record, "OLD")
+	writer.deleteErr = errors.New("已打单数据不能清除")
+	outcome := applyClaimedInnerCode(context.Background(), writer, record)
+	if outcome.Status != model.InnerCodeFailed || writer.deleteCount != 1 || writer.updateCount != 0 {
+		t.Fatalf("outcome=%+v delete=%d update=%d", outcome, writer.deleteCount, writer.updateCount)
+	}
+}
+
+func TestApplyClaimedInnerCode_写入未知结果不复读也不重试(t *testing.T) {
+	record := innerCodeApplyTestRecord("")
+	writer := innerCodeApplyTestWriter(record, "")
+	writer.updateErr = fmtUnknownInnerCodeWriteError()
+	outcome := applyClaimedInnerCode(context.Background(), writer, record)
+	if outcome.Status != model.InnerCodeNeedsCheck || writer.updateCount != 1 || writer.readCount != 1 {
+		t.Fatalf("outcome=%+v update=%d read=%d", outcome, writer.updateCount, writer.readCount)
+	}
+}
+
+func TestApplyClaimedInnerCode_采购字段出现后停止(t *testing.T) {
+	record := innerCodeApplyTestRecord("")
+	writer := innerCodeApplyTestWriter(record, "")
+	writer.stock.Details[0].Raw["purchaseCode"] = "CG-1"
+	outcome := applyClaimedInnerCode(context.Background(), writer, record)
+	if outcome.Status != model.InnerCodeSkipped || writer.updateCount != 0 {
+		t.Fatalf("outcome=%+v update=%d", outcome, writer.updateCount)
+	}
+}
+
+func TestApplyClaimedInnerCode_档口身份变化后停止(t *testing.T) {
+	record := innerCodeApplyTestRecord("")
+	record.SybSKU = "A#1"
+	writer := innerCodeApplyTestWriter(record, "")
+	writer.stock.Details[0].Raw["sku"] = "B#2"
+	outcome := applyClaimedInnerCode(context.Background(), writer, record)
+	if outcome.Status != model.InnerCodeSkipped || writer.updateCount != 0 {
+		t.Fatalf("outcome=%+v update=%d", outcome, writer.updateCount)
+	}
+}
+
+func innerCodeApplyTestRecord(oldCode string) model.InnerCodeRecord {
+	return model.InnerCodeRecord{ID: 1, StockID: 10, DetailID: 20, SybSpec: "黑色,M",
+		InnerCode: "DK-001", RemoteInnerCode: oldCode, Status: model.InnerCodeApplying}
+}
+
+func innerCodeApplyTestWriter(record model.InnerCodeRecord, currentCode string) *fakeInnerCodeWriter {
+	item := syb.DetailItem{ID: record.DetailID, ProductSpec: record.SybSpec, Raw: map[string]any{
+		"id": record.DetailID, "productSpec": record.SybSpec, "innerExpCode": currentCode,
+		"purchasePlatform": "", "purchaseCode": "",
+	}}
+	return &fakeInnerCodeWriter{stock: syb.StockDetail{ID: record.StockID, Details: []syb.DetailItem{item}}}
+}
+
+func fmtUnknownInnerCodeWriteError() error {
+	return errors.Join(syb.ErrWriteResultUnknown, errors.New("timeout"))
+}
diff --git a/admin/syb/client.go b/admin/syb/client.go
index 286282e..f6b3495 100644
--- a/admin/syb/client.go
+++ b/admin/syb/client.go
@@ -24,6 +24,7 @@ import (
 	"strconv"
 	"strings"
 	"time"
+	"unicode/utf8"
 )
 
 // ErrSessionInvalid 表示服务端**明确**判定当前会话未登录或已过期
@@ -37,6 +38,15 @@ import (
 // 还可能把本来有效的会话丢掉，见 §3.5 的理由和工单 #46。
 var ErrSessionInvalid = errors.New("顺运宝会话未登录或已过期")
 
+// ErrWriteResultUnknown 表示写请求可能已经到达顺运宝，但客户端无法确认结果。
+// 调用方只能重新读取核对，绝不能自动重发同一个写请求。
+var ErrWriteResultUnknown = errors.New("顺运宝写入结果未知")
+
+type requestOutcomeUnknownError struct{ err error }
+
+func (e requestOutcomeUnknownError) Error() string { return e.err.Error() }
+func (e requestOutcomeUnknownError) Unwrap() error { return e.err }
+
 // Client 是一个顺运宝 ERP 会话：验证码、登录、货运单查询共用同一个
 // http.Client（同一个 Cookie Jar）。
 //
@@ -177,20 +187,20 @@ func (c *Client) do(ctx context.Context, method, path string, query url.Values,
 	if err != nil {
 		// 网络故障（超时、连不上、DNS 失败……）——`[必须]` 不能当成"未登录"，
 		// 见 ErrSessionInvalid 的注释和 08 §3.5。
-		return nil, fmt.Errorf("请求顺运宝接口 %s 失败（网络问题，不代表未登录）: %w", path, err)
+		return nil, requestOutcomeUnknownError{fmt.Errorf("请求顺运宝接口 %s 失败（网络问题，不代表未登录）: %w", path, err)}
 	}
 	defer resp.Body.Close()
 
 	raw, err := io.ReadAll(resp.Body)
 	if err != nil {
-		return nil, fmt.Errorf("读取顺运宝接口 %s 响应失败: %w", path, err)
+		return nil, requestOutcomeUnknownError{fmt.Errorf("读取顺运宝接口 %s 响应失败: %w", path, err)}
 	}
 
 	if resp.StatusCode == http.StatusUnauthorized || resp.StatusCode == http.StatusForbidden {
 		return nil, fmt.Errorf("顺运宝接口 %s 返回 %d: %w", path, resp.StatusCode, ErrSessionInvalid)
 	}
 	if resp.StatusCode >= http.StatusInternalServerError {
-		return nil, fmt.Errorf("顺运宝接口 %s 返回 %d（服务端故障，不代表未登录）", path, resp.StatusCode)
+		return nil, requestOutcomeUnknownError{fmt.Errorf("顺运宝接口 %s 返回 %d（服务端故障，不代表未登录）", path, resp.StatusCode)}
 	}
 	if resp.StatusCode != http.StatusOK {
 		return nil, fmt.Errorf("顺运宝接口 %s 返回意外状态码 %d", path, resp.StatusCode)
@@ -198,7 +208,7 @@ func (c *Client) do(ctx context.Context, method, path string, query url.Values,
 
 	var env envelope
 	if err := json.Unmarshal(raw, &env); err != nil {
-		return nil, fmt.Errorf("顺运宝接口 %s 响应不是合法 JSON（格式错误，不代表未登录）: %w", path, err)
+		return nil, requestOutcomeUnknownError{fmt.Errorf("顺运宝接口 %s 响应不是合法 JSON（格式错误，不代表未登录）: %w", path, err)}
 	}
 	if !env.Status {
 		if isSessionInvalidMessage(env.Msg, env.Code) {
@@ -631,6 +641,53 @@ func (c *Client) DetailListByStock(ctx context.Context, ids []int64) ([]StockDet
 	return out, nil
 }
 
+// DeleteInnerCode 清除一个货运明细的 innerExpCode。
+// 请求只发送一次；结果未知时返回 ErrWriteResultUnknown，调用方不得重试。
+func (c *Client) DeleteInnerCode(ctx context.Context, detailID int64) error {
+	if detailID <= 0 {
+		return fmt.Errorf("detailId 必须是正整数")
+	}
+	_, err := c.do(ctx, http.MethodGet, "/am/stock/detail/deleteInnerCode",
+		url.Values{"detailId": {strconv.FormatInt(detailID, 10)}}, nil)
+	return classifyInnerCodeWriteError(err)
+}
+
+// UpdateDetailCode 把档口入库码写入货运明细的 innerExpCode。
+// 请求只发送一次；结果未知时返回 ErrWriteResultUnknown，调用方不得重试。
+func (c *Client) UpdateDetailCode(ctx context.Context, stockID, detailID int64, code string) error {
+	code = strings.TrimSpace(code)
+	if stockID <= 0 || detailID <= 0 {
+		return fmt.Errorf("货运单 id 和 detailId 必须是正整数")
+	}
+	if code == "" {
+		return fmt.Errorf("code 不能为空")
+	}
+	if utf8.RuneCountInString(code) > 128 {
+		return fmt.Errorf("code 不能超过 128 个字符")
+	}
+	for _, character := range code {
+		if character < 32 || character == 127 {
+			return fmt.Errorf("code 不能包含控制字符")
+		}
+	}
+	_, err := c.do(ctx, http.MethodGet, "/am/stock/detail/updateDetailCode", url.Values{
+		"t": {"0"}, "id": {strconv.FormatInt(stockID, 10)},
+		"detailId": {strconv.FormatInt(detailID, 10)}, "code": {code},
+	}, nil)
+	return classifyInnerCodeWriteError(err)
+}
+
+func classifyInnerCodeWriteError(err error) error {
+	if err == nil {
+		return nil
+	}
+	var unknown requestOutcomeUnknownError
+	if errors.As(err, &unknown) {
+		return fmt.Errorf("%w：%v", ErrWriteResultUnknown, err)
+	}
+	return err
+}
+
 // ---------- 类型转换：JSON 数字/字符串统一转 ----------
 
 // toInt64 兼容 JSON 数字被 encoding/json 解成 float64、以及顺运宝个别
diff --git a/admin/syb/client_test.go b/admin/syb/client_test.go
index 63cf554..fc06b9e 100644
--- a/admin/syb/client_test.go
+++ b/admin/syb/client_test.go
@@ -431,6 +431,85 @@ func TestClient_DetailListByStock_超过100个id报错(t *testing.T) {
 	}
 }
 
+func TestClient_InnerCodeWrite_参数和路径正确且只发送一次(t *testing.T) {
+	var requests atomic.Int32
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		requests.Add(1)
+		w.Header().Set("Content-Type", "application/json")
+		switch r.URL.Path {
+		case "/am/stock/detail/deleteInnerCode":
+			if r.URL.Query().Get("detailId") != "22" {
+				t.Errorf("delete query=%v", r.URL.Query())
+			}
+		case "/am/stock/detail/updateDetailCode":
+			query := r.URL.Query()
+			if query.Get("t") != "0" || query.Get("id") != "11" || query.Get("detailId") != "22" || query.Get("code") != "DK-001" {
+				t.Errorf("update query=%v", query)
+			}
+		default:
+			t.Errorf("意外路径 %s", r.URL.Path)
+		}
+		io.WriteString(w, `{"status":true,"msg":"成功","data":null}`)
+	}))
+	defer server.Close()
+	client, err := New(server.URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := client.DeleteInnerCode(context.Background(), 22); err != nil {
+		t.Fatal(err)
+	}
+	if err := client.UpdateDetailCode(context.Background(), 11, 22, " DK-001 "); err != nil {
+		t.Fatal(err)
+	}
+	if requests.Load() != 2 {
+		t.Fatalf("每个写动作只能发一次请求，实际总请求 %d", requests.Load())
+	}
+}
+
+func TestClient_InnerCodeWrite_未知结果与明确业务失败分开(t *testing.T) {
+	for _, tc := range []struct {
+		name        string
+		status      int
+		body        string
+		wantUnknown bool
+	}{
+		{"服务端故障", http.StatusInternalServerError, `oops`, true},
+		{"成功响应损坏", http.StatusOK, `not-json`, true},
+		{"明确业务失败", http.StatusOK, `{"status":false,"msg":"已打单数据不能清除","code":1}`, false},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				w.WriteHeader(tc.status)
+				io.WriteString(w, tc.body)
+			}))
+			defer server.Close()
+			client, _ := New(server.URL)
+			err := client.DeleteInnerCode(context.Background(), 22)
+			if err == nil || errors.Is(err, ErrWriteResultUnknown) != tc.wantUnknown {
+				t.Fatalf("err=%v unknown=%v want=%v", err, errors.Is(err, ErrWriteResultUnknown), tc.wantUnknown)
+			}
+		})
+	}
+}
+
+func TestClient_UpdateDetailCode_本地校验失败不发送请求(t *testing.T) {
+	var requests atomic.Int32
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		requests.Add(1)
+	}))
+	defer server.Close()
+	client, _ := New(server.URL)
+	for _, code := range []string{"", "bad\ncode", strings.Repeat("长", 129)} {
+		if err := client.UpdateDetailCode(context.Background(), 1, 2, code); err == nil {
+			t.Errorf("code=%q 应被拒绝", code)
+		}
+	}
+	if requests.Load() != 0 {
+		t.Fatalf("本地校验失败不应发请求，实际 %d", requests.Load())
+	}
+}
+
 // ── 业务失败但不是登录问题 ──────────────────────────────
 
 func TestClient_业务失败但不是登录问题时返回普通错误(t *testing.T) {
diff --git a/docs/admin/08-顺运宝接口.md b/docs/admin/08-顺运宝接口.md
index 6bcff88..03bfd56 100644
--- a/docs/admin/08-顺运宝接口.md
+++ b/docs/admin/08-顺运宝接口.md
@@ -410,6 +410,23 @@ SKU（平均每商品 1.17 个），**查无此 SKU 是常态**，不是异常
 `[建议]` 登录后**只调 `/am/user/get` 验证会话**，其余几个是网页自己的初始化请求，
 Go 侧不用跟着调。
 
+### 7.1 档口入库码写入（工单 #234）
+
+档口入库码最终写入货运明细的 `innerExpCode`（页面名称“快递单号”）。两个写接口来自
+现有 Python 流程和线上响应样本：
+
+```text
+GET /am/stock/detail/deleteInnerCode?detailId={detailID}
+GET /am/stock/detail/updateDetailCode?t=0&id={stockID}&detailId={detailID}&code={innerCode}
+```
+
+- 旧值为空时不调用删除；旧值非空时，只有删除明确成功才发送写入。
+- 删除和写入请求都只允许发送一次，不使用自动重试。超时、5xx、响应读取失败或成功响应
+  无法解析时，结果可能已经在远端生效，必须标为“需核对”。
+- 每条写入前重新调用 `listByStock`，核对 stock/detail、规格、采购平台、采购单号和规划时
+  的旧值；写入后再次读取，只有 `innerExpCode` 与目标一致才标为已回写。
+- “重新核对”只调用 `listByStock`，绝不能再次调用上述两个写接口。
+
 ---
 
 ## 8. 实现时的固定约束