diff --git a/internal/authz/authorizer.go b/internal/authz/authorizer.go
index b9b99c6c..8dba3bd2 100644
--- a/internal/authz/authorizer.go
+++ b/internal/authz/authorizer.go
@@ -8,12 +8,14 @@ import (
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
+
+	"chat-agent-system/internal/docduty"
 )
 
 var (
-	ErrForbidden        = errors.New("authz: forbidden")
-	ErrProjectNotFound  = errors.New("authz: project not found")
-	ErrUnauthenticated  = errors.New("authz: unauthenticated")
+	ErrForbidden       = errors.New("authz: forbidden")
+	ErrProjectNotFound = errors.New("authz: project not found")
+	ErrUnauthenticated = errors.New("authz: unauthenticated")
 )
 
 const (
@@ -32,14 +34,21 @@ var allowedProjectRoles = map[string]struct{}{
 
 // ProjectMemberRecord 项目成员 API 视图。
 type ProjectMemberRecord struct {
-	ID          int64  `json:"id,omitempty"`
-	ProjectID   int64  `json:"project_id,omitempty"`
-	UserID      int64  `json:"user_id"`
-	Username    string `json:"username,omitempty"`
-	Name        string `json:"name,omitempty"`
-	ProjectRole string `json:"project_role"`
-	Status      string `json:"status"`
-	JoinedAt    string `json:"joined_at,omitempty"`
+	ID           int64  `json:"id,omitempty"`
+	ProjectID    int64  `json:"project_id,omitempty"`
+	UserID       int64  `json:"user_id"`
+	Username     string `json:"username,omitempty"`
+	Name         string `json:"name,omitempty"`
+	ProjectRole  string `json:"project_role"`
+	DocumentDuty string `json:"document_duty,omitempty"`
+	Status       string `json:"status"`
+	JoinedAt     string `json:"joined_at,omitempty"`
+}
+
+// MemberUpsert 项目访问角色 + 可选文档职责。
+type MemberUpsert struct {
+	ProjectRole  string
+	DocumentDuty *string
 }
 
 // Authorizer 项目级对象授权。
@@ -55,20 +64,13 @@ func (a *Authorizer) enabled() bool {
 	return a != nil && a.pool != nil
 }
 
-// AddOwnerOnCreate 项目创建时写入 owner 成员关系。
+// AddOwnerOnCreate 项目创建时写入 owner 成员关系，并默认编制职责。
 func (a *Authorizer) AddOwnerOnCreate(ctx context.Context, projectID, userID int64) error {
-	if !a.enabled() || projectID <= 0 || userID <= 0 {
-		return nil
-	}
-	_, err := a.pool.Exec(ctx, `
-		INSERT INTO project_members (project_id, user_id, project_role, status, joined_at, updated_at)
-		VALUES ($1, $2, $3, $4, now(), now())
-		ON CONFLICT (project_id, user_id) DO UPDATE SET
-			project_role = EXCLUDED.project_role,
-			status = EXCLUDED.status,
-			updated_at = now()
-	`, projectID, userID, RoleOwner, StatusActive)
-	return err
+	duty := docduty.DutyAuthor
+	return a.UpsertProjectMemberSpec(ctx, projectID, userID, MemberUpsert{
+		ProjectRole:  RoleOwner,
+		DocumentDuty: &duty,
+	})
 }
 
 // IsProjectMember 判断用户是否为项目 active 成员或创建人。
@@ -198,7 +200,7 @@ func (a *Authorizer) ListProjectMembers(ctx context.Context, projectID int64) ([
 		SELECT pm.id, pm.project_id, pm.user_id,
 		       COALESCE(NULLIF(u.username, ''), u.account_id, '') AS username,
 		       COALESCE(u.name, '') AS name,
-		       pm.project_role, pm.status, pm.joined_at
+		       pm.project_role, COALESCE(pm.document_duty, ''), pm.status, pm.joined_at
 		FROM project_members pm
 		JOIN users u ON u.id = pm.user_id
 		WHERE pm.project_id = $1
@@ -215,7 +217,7 @@ func (a *Authorizer) ListProjectMembers(ctx context.Context, projectID int64) ([
 		if err := rows.Scan(
 			&rec.ID, &rec.ProjectID, &rec.UserID,
 			&rec.Username, &rec.Name,
-			&rec.ProjectRole, &rec.Status, &joined,
+			&rec.ProjectRole, &rec.DocumentDuty, &rec.Status, &joined,
 		); err != nil {
 			return nil, err
 		}
@@ -225,26 +227,70 @@ func (a *Authorizer) ListProjectMembers(ctx context.Context, projectID int64) ([
 	return out, rows.Err()
 }
 
-// UpsertProjectMember 新增或更新成员角色（禁止 docgov 专用角色名）。
+// UpsertProjectMember 新增或更新成员访问角色（禁止把 author/reviewer/approver 写入 project_role）。
 func (a *Authorizer) UpsertProjectMember(ctx context.Context, projectID, userID int64, projectRole string) error {
+	return a.UpsertProjectMemberSpec(ctx, projectID, userID, MemberUpsert{ProjectRole: projectRole})
+}
+
+// UpsertProjectMemberSpec 写入访问角色，并可选独占 document_duty。
+func (a *Authorizer) UpsertProjectMemberSpec(ctx context.Context, projectID, userID int64, spec MemberUpsert) error {
 	if projectID <= 0 || userID <= 0 {
 		return fmt.Errorf("authz: invalid project or user id")
 	}
-	if err := validateProjectRole(projectRole); err != nil {
+	if err := validateProjectRole(spec.ProjectRole); err != nil {
 		return err
 	}
+	var duty string
+	var err error
+	if spec.DocumentDuty != nil {
+		duty, err = docduty.NormalizeDocumentDuty(*spec.DocumentDuty)
+		if err != nil {
+			return err
+		}
+	}
 	if !a.enabled() {
 		return nil
 	}
-	_, err := a.pool.Exec(ctx, `
-		INSERT INTO project_members (project_id, user_id, project_role, status, joined_at, updated_at)
-		VALUES ($1, $2, $3, $4, now(), now())
-		ON CONFLICT (project_id, user_id) DO UPDATE SET
-			project_role = EXCLUDED.project_role,
-			status = EXCLUDED.status,
-			updated_at = now()
-	`, projectID, userID, projectRole, StatusActive)
-	return err
+	tx, err := a.pool.Begin(ctx)
+	if err != nil {
+		return err
+	}
+	defer func() { _ = tx.Rollback(ctx) }()
+
+	if spec.DocumentDuty != nil && duty != docduty.DutyNone {
+		if _, err := tx.Exec(ctx, `
+			UPDATE project_members
+			SET document_duty = '', updated_at = now()
+			WHERE project_id = $1 AND document_duty = $2 AND user_id <> $3 AND status = $4
+		`, projectID, duty, userID, StatusActive); err != nil {
+			return err
+		}
+	}
+
+	if spec.DocumentDuty != nil {
+		_, err = tx.Exec(ctx, `
+			INSERT INTO project_members (project_id, user_id, project_role, document_duty, status, joined_at, updated_at)
+			VALUES ($1, $2, $3, $4, $5, now(), now())
+			ON CONFLICT (project_id, user_id) DO UPDATE SET
+				project_role = EXCLUDED.project_role,
+				document_duty = EXCLUDED.document_duty,
+				status = EXCLUDED.status,
+				updated_at = now()
+		`, projectID, userID, spec.ProjectRole, duty, StatusActive)
+	} else {
+		_, err = tx.Exec(ctx, `
+			INSERT INTO project_members (project_id, user_id, project_role, status, joined_at, updated_at)
+			VALUES ($1, $2, $3, $4, now(), now())
+			ON CONFLICT (project_id, user_id) DO UPDATE SET
+				project_role = EXCLUDED.project_role,
+				status = EXCLUDED.status,
+				updated_at = now()
+		`, projectID, userID, spec.ProjectRole, StatusActive)
+	}
+	if err != nil {
+		return err
+	}
+	return tx.Commit(ctx)
 }
 
 // SetProjectMemberStatus 更新成员状态（如 exited）。
diff --git a/internal/authz/service_test.go b/internal/authz/service_test.go
index 476238ae..30dfb7ab 100644
--- a/internal/authz/service_test.go
+++ b/internal/authz/service_test.go
@@ -34,4 +34,11 @@ func TestUpsertProjectMember_RejectsDocRolesWithoutDB(t *testing.T) {
 	if err := a.UpsertProjectMember(context.Background(), 1, 2, authz.RoleOwner); err != nil {
 		t.Fatalf("owner should be allowed: %v", err)
 	}
+	bad := "viewer"
+	if err := a.UpsertProjectMemberSpec(context.Background(), 1, 2, authz.MemberUpsert{
+		ProjectRole:  authz.RoleMember,
+		DocumentDuty: &bad,
+	}); err == nil {
+		t.Fatal("document_duty=viewer must be rejected")
+	}
 }
diff --git a/internal/bizdev/document_duty_resolve_test.go b/internal/bizdev/document_duty_resolve_test.go
new file mode 100644
index 00000000..e519fc78
--- /dev/null
+++ b/internal/bizdev/document_duty_resolve_test.go
@@ -0,0 +1,40 @@
+package bizdev
+
+import (
+	"context"
+	"testing"
+
+	"chat-agent-system/internal/docduty"
+)
+
+func TestResolveTaskDocumentDuties_UsesCreatorNotHardcodedReviewer(t *testing.T) {
+	req := TaskRunRequest{
+		UserID: 170, ProjectID: 6145,
+		AuthorName: "编制人A",
+	}
+	got := resolveTaskDocumentDuties(context.Background(), nil, req)
+	if got.Author.UserID != 170 {
+		t.Fatalf("author want 170 got %+v", got.Author)
+	}
+	if got.Reviewer.UserID == 2 || got.Approver.UserID == 3 {
+		t.Fatalf("must not invent hardcoded 2/3: %+v", got)
+	}
+	if got.Reviewer.UserID != 0 {
+		t.Fatalf("no project members → reviewer empty, got %+v", got.Reviewer)
+	}
+}
+
+func TestResolveTaskDocumentDuties_IgnoresNonMemberRequestReviewer(t *testing.T) {
+	req := TaskRunRequest{
+		UserID: 170, ReviewerID: 2, ReviewerName: "审核负责人",
+	}
+	got := resolveTaskDocumentDuties(context.Background(), nil, req)
+	if got.Reviewer.UserID != 0 {
+		t.Fatalf("request reviewer 2 is not a member: %+v", got.Reviewer)
+	}
+}
+
+func TestBindingFromDocRoundTrip(t *testing.T) {
+	// compile-time guard that helper stays aligned with Resolve slots
+	_ = docduty.Binding{}
+}
diff --git a/internal/bizdev/service.go b/internal/bizdev/service.go
index b2e5c60c..8b5e4220 100644
--- a/internal/bizdev/service.go
+++ b/internal/bizdev/service.go
@@ -16,6 +16,7 @@ import (
 	"chat-agent-system/internal/config"
 	"chat-agent-system/internal/ctxmgr"
 	"chat-agent-system/internal/db"
+	"chat-agent-system/internal/docduty"
 	"chat-agent-system/internal/docgov"
 	"chat-agent-system/internal/docrevision"
 	"chat-agent-system/internal/freedoc"
@@ -453,28 +454,17 @@ func (s *Service) ExecuteTask(ctx context.Context, req TaskRunRequest) (*TaskRun
 		}
 	}
 
-	authorID := req.AuthorID
-	if authorID == 0 {
-		authorID = req.UserID
-	}
-	authorName := req.AuthorName
+	duties := resolveTaskDocumentDuties(ctx, s.pool, req)
+	authorID, authorName := duties.Author.UserID, duties.Author.Name
+	reviewerID, reviewerName := duties.Reviewer.UserID, duties.Reviewer.Name
+	approverID, approverName := duties.Approver.UserID, duties.Approver.Name
 	if authorName == "" {
 		authorName = "编制工程师"
 	}
-	reviewerID := req.ReviewerID
-	if reviewerID == 0 {
-		reviewerID = 2
-	}
-	reviewerName := req.ReviewerName
-	if reviewerName == "" {
+	if reviewerName == "" && reviewerID > 0 {
 		reviewerName = "审核负责人"
 	}
-	approverID := req.ApproverID
-	if approverID == 0 {
-		approverID = 3
-	}
-	approverName := req.ApproverName
-	if approverName == "" {
+	if approverName == "" && approverID > 0 {
 		approverName = "批准负责人"
 	}
 
@@ -489,6 +479,14 @@ func (s *Service) ExecuteTask(ctx context.Context, req TaskRunRequest) (*TaskRun
 			"V0.5_feasibility", req.WorkDir,
 			authorID, authorName, reviewerID, reviewerName, approverID, approverName,
 		)
+		if s.pool != nil && req.ProjectID > 0 {
+			if assigned, _, healErr := docduty.HealProjectDocuments(ctx, s.pool, req.ProjectID); healErr == nil && docRec != nil {
+				if members, creator, loadErr := docduty.LoadProjectMembers(ctx, s.pool, req.ProjectID); loadErr == nil {
+					next, _ := docduty.HealBinding(bindingFromDoc(docRec), assigned, docduty.ActiveMemberIDs(members, creator))
+					writeBindingToDoc(docRec, next)
+				}
+			}
+		}
 
 		if req.ForceDirectEdit {
 			if docRec != nil && docRec.IsLocked {
@@ -1297,3 +1295,44 @@ func (s *Service) InspectWorkspace(ctx context.Context, workDir string) (*squad.
 func (s *Service) ResumeOrModifyWorkspace(ctx context.Context, req squad.ModifyWorkflowRequest) (*squad.SquadRunResult, error) {
 	return s.squad.ResumeOrModifyWorkspace(ctx, req)
 }
+
+func resolveTaskDocumentDuties(ctx context.Context, pool *pgxpool.Pool, req TaskRunRequest) docduty.Binding {
+	reqDuties := docduty.RequestDuties{
+		AuthorID: req.AuthorID, AuthorName: req.AuthorName,
+		ReviewerID: req.ReviewerID, ReviewerName: req.ReviewerName,
+		ApproverID: req.ApproverID, ApproverName: req.ApproverName,
+	}
+	if reqDuties.AuthorID == 0 {
+		reqDuties.AuthorID = req.UserID
+	}
+	if pool != nil && req.ProjectID > 0 {
+		if bound, err := docduty.ResolveProject(ctx, pool, req.ProjectID, reqDuties); err == nil {
+			if bound.Author.UserID == 0 && req.UserID > 0 {
+				bound.Author = docduty.Holder{UserID: req.UserID, Name: strings.TrimSpace(req.AuthorName)}
+			}
+			return bound
+		}
+	}
+	creator := docduty.Holder{UserID: req.UserID, Name: strings.TrimSpace(req.AuthorName)}
+	return docduty.Resolve(nil, creator, reqDuties)
+}
+
+func bindingFromDoc(doc *docgov.DocumentRecord) docduty.Binding {
+	if doc == nil {
+		return docduty.Binding{}
+	}
+	return docduty.Binding{
+		Author:   docduty.Holder{UserID: doc.AuthorID, Name: doc.AuthorName},
+		Reviewer: docduty.Holder{UserID: doc.ReviewerID, Name: doc.ReviewerName},
+		Approver: docduty.Holder{UserID: doc.ApproverID, Name: doc.ApproverName},
+	}
+}
+
+func writeBindingToDoc(doc *docgov.DocumentRecord, bound docduty.Binding) {
+	if doc == nil {
+		return
+	}
+	doc.AuthorID, doc.AuthorName = bound.Author.UserID, bound.Author.Name
+	doc.ReviewerID, doc.ReviewerName = bound.Reviewer.UserID, bound.Reviewer.Name
+	doc.ApproverID, doc.ApproverName = bound.Approver.UserID, bound.Approver.Name
+}
diff --git a/internal/docduty/resolve.go b/internal/docduty/resolve.go
new file mode 100644
index 00000000..e27cc064
--- /dev/null
+++ b/internal/docduty/resolve.go
@@ -0,0 +1,174 @@
+package docduty
+
+import (
+	"fmt"
+	"strings"
+)
+
+const (
+	DutyNone     = ""
+	DutyAuthor   = "author"
+	DutyReviewer = "reviewer"
+	DutyApprover = "approver"
+	StatusActive = "active"
+)
+
+// Holder 某一文档职责的用户。
+type Holder struct {
+	UserID int64
+	Name   string
+}
+
+// Binding 一份受控文档应采用的编制/审核/批准职责。
+type Binding struct {
+	Author   Holder
+	Reviewer Holder
+	Approver Holder
+}
+
+// Member 项目成员快照（访问角色与文档职责分离）。
+type Member struct {
+	UserID       int64
+	Name         string
+	Status       string
+	ProjectRole  string
+	DocumentDuty string
+}
+
+// RequestDuties 任务请求里客户端声称的职责；仅当该用户是在任成员时才可采用。
+type RequestDuties struct {
+	AuthorID     int64
+	AuthorName   string
+	ReviewerID   int64
+	ReviewerName string
+	ApproverID   int64
+	ApproverName string
+}
+
+// NormalizeDocumentDuty 校验 document_duty。空串表示无文档职责。
+func NormalizeDocumentDuty(raw string) (string, error) {
+	duty := strings.TrimSpace(strings.ToLower(raw))
+	switch duty {
+	case DutyNone, DutyAuthor, DutyReviewer, DutyApprover:
+		return duty, nil
+	default:
+		return "", fmt.Errorf("docduty: invalid document_duty %q", raw)
+	}
+}
+
+// ActiveMemberIDs 在任成员（含创建者）。
+func ActiveMemberIDs(members []Member, creator Holder) map[int64]struct{} {
+	ids := make(map[int64]struct{}, len(members)+1)
+	if creator.UserID > 0 {
+		ids[creator.UserID] = struct{}{}
+	}
+	for _, m := range members {
+		if m.UserID > 0 && (m.Status == "" || m.Status == StatusActive) {
+			ids[m.UserID] = struct{}{}
+		}
+	}
+	return ids
+}
+
+func isActiveMember(m Member) bool {
+	return m.UserID > 0 && (m.Status == "" || m.Status == StatusActive)
+}
+
+func dutyHolder(members []Member, duty string) Holder {
+	var found Holder
+	for _, m := range members {
+		if !isActiveMember(m) || m.DocumentDuty != duty {
+			continue
+		}
+		found = Holder{UserID: m.UserID, Name: strings.TrimSpace(m.Name)}
+	}
+	return found
+}
+
+func pickMember(reqID int64, reqName string, memberIDs map[int64]struct{}, members []Member) Holder {
+	if reqID <= 0 {
+		return Holder{}
+	}
+	if _, ok := memberIDs[reqID]; !ok {
+		return Holder{}
+	}
+	name := strings.TrimSpace(reqName)
+	for _, m := range members {
+		if m.UserID == reqID && isActiveMember(m) && strings.TrimSpace(m.Name) != "" {
+			name = strings.TrimSpace(m.Name)
+			break
+		}
+	}
+	return Holder{UserID: reqID, Name: name}
+}
+
+// Resolve 以项目 document_duty 为权威。禁止回落到硬编码 2/3。
+// author：指定编制人 → 创建者 → 请求 id（须为成员）。
+// reviewer/approver：指定职责 → 请求 id（须为成员）→ 空。
+func Resolve(members []Member, creator Holder, req RequestDuties) Binding {
+	memberIDs := ActiveMemberIDs(members, creator)
+	out := Binding{}
+
+	if h := dutyHolder(members, DutyAuthor); h.UserID > 0 {
+		out.Author = h
+	} else if creator.UserID > 0 {
+		out.Author = creator
+	} else {
+		out.Author = pickMember(req.AuthorID, req.AuthorName, memberIDs, members)
+	}
+
+	if h := dutyHolder(members, DutyReviewer); h.UserID > 0 {
+		out.Reviewer = h
+	} else {
+		out.Reviewer = pickMember(req.ReviewerID, req.ReviewerName, memberIDs, members)
+	}
+
+	if h := dutyHolder(members, DutyApprover); h.UserID > 0 {
+		out.Approver = h
+	} else {
+		out.Approver = pickMember(req.ApproverID, req.ApproverName, memberIDs, members)
+	}
+
+	return out
+}
+
+// DutyMissing 当前职责缺失或指向非成员（含历史硬编码占位 id）。
+func DutyMissing(currentID int64, memberIDs map[int64]struct{}) bool {
+	if currentID <= 0 {
+		return true
+	}
+	_, ok := memberIDs[currentID]
+	return !ok
+}
+
+func healSlot(current, assigned Holder, memberIDs map[int64]struct{}) (Holder, bool) {
+	if !DutyMissing(current.UserID, memberIDs) {
+		return current, false
+	}
+	if assigned.UserID <= 0 {
+		return current, false
+	}
+	if current.UserID == assigned.UserID && current.Name == assigned.Name {
+		return current, false
+	}
+	return assigned, true
+}
+
+// HealBinding 仅回填缺失/非成员槽位；已是在任成员的职责不覆盖，避免作者/批准人串位。
+func HealBinding(current, assigned Binding, memberIDs map[int64]struct{}) (Binding, bool) {
+	out := current
+	changed := false
+	if next, ok := healSlot(current.Author, assigned.Author, memberIDs); ok {
+		out.Author = next
+		changed = true
+	}
+	if next, ok := healSlot(current.Reviewer, assigned.Reviewer, memberIDs); ok {
+		out.Reviewer = next
+		changed = true
+	}
+	if next, ok := healSlot(current.Approver, assigned.Approver, memberIDs); ok {
+		out.Approver = next
+		changed = true
+	}
+	return out, changed
+}
diff --git a/internal/docduty/resolve_test.go b/internal/docduty/resolve_test.go
new file mode 100644
index 00000000..73c29a55
--- /dev/null
+++ b/internal/docduty/resolve_test.go
@@ -0,0 +1,161 @@
+package docduty
+
+import (
+	"sync"
+	"testing"
+)
+
+func sampleMembers() ([]Member, Holder) {
+	creator := Holder{UserID: 170, Name: "编制人A"}
+	members := []Member{
+		{UserID: 170, Name: "编制人A", Status: StatusActive, ProjectRole: "owner", DocumentDuty: DutyAuthor},
+		{UserID: 171, Name: "审核人B", Status: StatusActive, ProjectRole: "member", DocumentDuty: DutyReviewer},
+		{UserID: 3, Name: "李主管", Status: StatusActive, ProjectRole: "member", DocumentDuty: DutyNone},
+		{UserID: 4, Name: "王总监", Status: StatusActive, ProjectRole: "member", DocumentDuty: DutyApprover},
+	}
+	return members, creator
+}
+
+func TestResolve_AAuthorBReviewerCNone(t *testing.T) {
+	members, creator := sampleMembers()
+	got := Resolve(members, creator, RequestDuties{
+		AuthorID: 2, ReviewerID: 2, ApproverID: 3,
+		AuthorName: "编制工程师", ReviewerName: "审核负责人", ApproverName: "批准负责人",
+	})
+	if got.Author.UserID != 170 || got.Author.Name != "编制人A" {
+		t.Fatalf("author: %+v", got.Author)
+	}
+	if got.Reviewer.UserID != 171 || got.Reviewer.Name != "审核人B" {
+		t.Fatalf("reviewer: %+v", got.Reviewer)
+	}
+	if got.Approver.UserID != 4 || got.Approver.Name != "王总监" {
+		t.Fatalf("approver: %+v", got.Approver)
+	}
+	if got.Author.UserID == got.Reviewer.UserID || got.Reviewer.UserID == got.Approver.UserID {
+		t.Fatalf("duties swapped: %+v", got)
+	}
+	if got.Reviewer.UserID == 99 || got.Author.UserID == 99 {
+		t.Fatal("non-member C must not receive a duty")
+	}
+}
+
+func TestResolve_NeverDefaultsToHardcodedTwoOrThree(t *testing.T) {
+	creator := Holder{UserID: 170, Name: "编制人A"}
+	members := []Member{
+		{UserID: 170, Name: "编制人A", Status: StatusActive, ProjectRole: "owner", DocumentDuty: DutyAuthor},
+	}
+	got := Resolve(members, creator, RequestDuties{})
+	if got.Reviewer.UserID != 0 || got.Approver.UserID != 0 {
+		t.Fatalf("expected empty reviewer/approver, got %+v", got)
+	}
+	if got.Reviewer.UserID == 2 || got.Approver.UserID == 3 {
+		t.Fatal("hardcoded 2/3 must not be invented")
+	}
+}
+
+func TestResolve_RequestIDsOnlyIfMembers(t *testing.T) {
+	creator := Holder{UserID: 170, Name: "编制人A"}
+	members := []Member{
+		{UserID: 170, Name: "编制人A", Status: StatusActive, ProjectRole: "owner"},
+		{UserID: 171, Name: "审核人B", Status: StatusActive, ProjectRole: "member"},
+	}
+	got := Resolve(members, creator, RequestDuties{ReviewerID: 2, ReviewerName: "审核负责人"})
+	if got.Reviewer.UserID != 0 {
+		t.Fatalf("non-member request reviewer 2 must be ignored, got %+v", got.Reviewer)
+	}
+	got = Resolve(members, creator, RequestDuties{ReviewerID: 171, ReviewerName: "审核人B"})
+	if got.Reviewer.UserID != 171 {
+		t.Fatalf("member request reviewer must apply: %+v", got.Reviewer)
+	}
+}
+
+func TestHealBinding_PlaceholderNonMemberBackfillIdempotent(t *testing.T) {
+	members, creator := sampleMembers()
+	assigned := Resolve(members, creator, RequestDuties{})
+	memberIDs := ActiveMemberIDs(members, creator)
+
+	current := Binding{
+		Author:   Holder{UserID: 170, Name: "编制工程师"},
+		Reviewer: Holder{UserID: 2, Name: "审核负责人"},
+		Approver: Holder{UserID: 3, Name: "批准负责人"},
+	}
+	// 3 是在任成员：批准槽位不得被改写成别人。
+	first, changed := HealBinding(current, assigned, memberIDs)
+	if !changed {
+		t.Fatal("placeholder reviewer 2 must be healed")
+	}
+	if first.Reviewer.UserID != 171 {
+		t.Fatalf("reviewer want 171 got %+v", first.Reviewer)
+	}
+	if first.Author.UserID != 170 {
+		t.Fatalf("author must stay A: %+v", first.Author)
+	}
+	if first.Approver.UserID != 3 {
+		t.Fatalf("member approver 3 must not be swapped: %+v", first.Approver)
+	}
+
+	second, changedAgain := HealBinding(first, assigned, memberIDs)
+	if changedAgain {
+		t.Fatalf("heal must be idempotent, got %+v", second)
+	}
+	if second != first {
+		t.Fatalf("second pass changed binding: %+v vs %+v", first, second)
+	}
+}
+
+func TestHealBinding_ZeroDutyBackfill(t *testing.T) {
+	members, creator := sampleMembers()
+	assigned := Resolve(members, creator, RequestDuties{})
+	memberIDs := ActiveMemberIDs(members, creator)
+	got, changed := HealBinding(Binding{}, assigned, memberIDs)
+	if !changed || got.Reviewer.UserID != 171 || got.Author.UserID != 170 {
+		t.Fatalf("zero duties: changed=%v got=%+v", changed, got)
+	}
+}
+
+func TestResolveAndHeal_SecondDocumentInherits(t *testing.T) {
+	members, creator := sampleMembers()
+	first := Resolve(members, creator, RequestDuties{})
+	second := Resolve(members, creator, RequestDuties{})
+	if first.Reviewer.UserID != 171 || second.Reviewer.UserID != 171 {
+		t.Fatalf("second document must inherit reviewer B: first=%+v second=%+v", first, second)
+	}
+	if first.Author.UserID != second.Author.UserID || first.Approver.UserID != second.Approver.UserID {
+		t.Fatalf("second document duties diverged: %+v vs %+v", first, second)
+	}
+}
+
+func TestResolve_ConcurrentIdempotent(t *testing.T) {
+	members, creator := sampleMembers()
+	var wg sync.WaitGroup
+	errCh := make(chan string, 32)
+	for i := 0; i < 32; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			got := Resolve(members, creator, RequestDuties{ReviewerID: 2})
+			if got.Reviewer.UserID != 171 || got.Author.UserID != 170 {
+				errCh <- "resolve mismatch"
+			}
+			memberIDs := ActiveMemberIDs(members, creator)
+			healed, _ := HealBinding(Binding{Reviewer: Holder{UserID: 2, Name: "审核负责人"}}, got, memberIDs)
+			if healed.Reviewer.UserID != 171 {
+				errCh <- "heal mismatch"
+			}
+		}()
+	}
+	wg.Wait()
+	close(errCh)
+	for msg := range errCh {
+		t.Fatal(msg)
+	}
+}
+
+func TestNormalizeDocumentDuty(t *testing.T) {
+	if _, err := NormalizeDocumentDuty("reviewer"); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := NormalizeDocumentDuty("viewer"); err == nil {
+		t.Fatal("viewer is not a document duty")
+	}
+}
diff --git a/internal/docduty/store.go b/internal/docduty/store.go
new file mode 100644
index 00000000..e811ad2f
--- /dev/null
+++ b/internal/docduty/store.go
@@ -0,0 +1,155 @@
+package docduty
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+// LoadProjectMembers 读取项目在任/历史成员与创建者，供职责解析。
+func LoadProjectMembers(ctx context.Context, pool *pgxpool.Pool, projectID int64) ([]Member, Holder, error) {
+	if pool == nil || projectID <= 0 {
+		return nil, Holder{}, nil
+	}
+	var creator Holder
+	err := pool.QueryRow(ctx, `
+		SELECT COALESCE(p.creator_user_id, 0), COALESCE(u.name, '')
+		FROM projects p
+		LEFT JOIN users u ON u.id = p.creator_user_id
+		WHERE p.id = $1
+	`, projectID).Scan(&creator.UserID, &creator.Name)
+	if err != nil && err != pgx.ErrNoRows {
+		return nil, Holder{}, fmt.Errorf("docduty: load creator: %w", err)
+	}
+	creator.Name = strings.TrimSpace(creator.Name)
+
+	rows, err := pool.Query(ctx, `
+		SELECT pm.user_id, COALESCE(u.name, ''), COALESCE(pm.status, ''),
+		       COALESCE(pm.project_role, ''), COALESCE(pm.document_duty, '')
+		FROM project_members pm
+		JOIN users u ON u.id = pm.user_id
+		WHERE pm.project_id = $1
+		ORDER BY pm.user_id ASC
+	`, projectID)
+	if err != nil {
+		return nil, creator, fmt.Errorf("docduty: load members: %w", err)
+	}
+	defer rows.Close()
+
+	members := make([]Member, 0)
+	for rows.Next() {
+		var m Member
+		if err := rows.Scan(&m.UserID, &m.Name, &m.Status, &m.ProjectRole, &m.DocumentDuty); err != nil {
+			return nil, creator, err
+		}
+		m.Name = strings.TrimSpace(m.Name)
+		members = append(members, m)
+	}
+	return members, creator, rows.Err()
+}
+
+// ResolveProject 从库表解析项目默认文档职责。
+func ResolveProject(ctx context.Context, pool *pgxpool.Pool, projectID int64, req RequestDuties) (Binding, error) {
+	members, creator, err := LoadProjectMembers(ctx, pool, projectID)
+	if err != nil {
+		return Binding{}, err
+	}
+	return Resolve(members, creator, req), nil
+}
+
+type storedDocDuties struct {
+	DocID    string
+	Author   Holder
+	Reviewer Holder
+	Approver Holder
+}
+
+// BackfillMissingDocumentDuties 对项目内受控文档回填缺失/非成员职责；已是成员的槽位不覆盖。
+func BackfillMissingDocumentDuties(ctx context.Context, pool *pgxpool.Pool, projectID int64, assigned Binding) (int, error) {
+	if pool == nil || projectID <= 0 {
+		return 0, nil
+	}
+	members, creator, err := LoadProjectMembers(ctx, pool, projectID)
+	if err != nil {
+		return 0, err
+	}
+	memberIDs := ActiveMemberIDs(members, creator)
+
+	rows, err := pool.Query(ctx, `
+		SELECT doc_id,
+		       COALESCE(author_id, 0), COALESCE(author_name, ''),
+		       COALESCE(reviewer_id, 0), COALESCE(reviewer_name, ''),
+		       COALESCE(approver_id, 0), COALESCE(approver_name, '')
+		FROM document_records
+		WHERE project_id = $1 AND COALESCE(task_key, '') <> ''
+	`, projectID)
+	if err != nil {
+		return 0, fmt.Errorf("docduty: list documents: %w", err)
+	}
+	defer rows.Close()
+
+	pending := make([]storedDocDuties, 0)
+	for rows.Next() {
+		var rec storedDocDuties
+		if err := rows.Scan(
+			&rec.DocID,
+			&rec.Author.UserID, &rec.Author.Name,
+			&rec.Reviewer.UserID, &rec.Reviewer.Name,
+			&rec.Approver.UserID, &rec.Approver.Name,
+		); err != nil {
+			return 0, err
+		}
+		current := Binding{Author: rec.Author, Reviewer: rec.Reviewer, Approver: rec.Approver}
+		next, changed := HealBinding(current, assigned, memberIDs)
+		if !changed {
+			continue
+		}
+		rec.Author, rec.Reviewer, rec.Approver = next.Author, next.Reviewer, next.Approver
+		pending = append(pending, rec)
+	}
+	if err := rows.Err(); err != nil {
+		return 0, err
+	}
+
+	updated := 0
+	for _, rec := range pending {
+		tag, err := pool.Exec(ctx, `
+			UPDATE document_records
+			SET author_id = $2, author_name = $3,
+			    reviewer_id = $4, reviewer_name = $5,
+			    approver_id = $6, approver_name = $7,
+			    updated_at = now()
+			WHERE doc_id = $1 AND project_id = $8
+		`, rec.DocID, nullIfZero(rec.Author.UserID), rec.Author.Name,
+			nullIfZero(rec.Reviewer.UserID), rec.Reviewer.Name,
+			nullIfZero(rec.Approver.UserID), rec.Approver.Name,
+			projectID)
+		if err != nil {
+			return updated, fmt.Errorf("docduty: backfill %s: %w", rec.DocID, err)
+		}
+		if tag.RowsAffected() > 0 {
+			updated++
+		}
+	}
+	return updated, nil
+}
+
+func nullIfZero(id int64) any {
+	if id <= 0 {
+		return nil
+	}
+	return id
+}
+
+// HealProjectDocuments 解析项目职责并回填缺失文档槽位；第二次调用应为 0 行。
+func HealProjectDocuments(ctx context.Context, pool *pgxpool.Pool, projectID int64) (Binding, int, error) {
+	assigned, err := ResolveProject(ctx, pool, projectID, RequestDuties{})
+	if err != nil {
+		return Binding{}, 0, err
+	}
+	n, err := BackfillMissingDocumentDuties(ctx, pool, projectID, assigned)
+	return assigned, n, err
+}
diff --git a/internal/docduty/store_pg_test.go b/internal/docduty/store_pg_test.go
new file mode 100644
index 00000000..a92e5f5d
--- /dev/null
+++ b/internal/docduty/store_pg_test.go
@@ -0,0 +1,145 @@
+package docduty
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+
+	"chat-agent-system/internal/db"
+)
+
+func TestProjectReviewerDutySync_PG(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping PostgreSQL duty sync integration in -short")
+	}
+	dsn := db.SkipIfNoTestDatabaseURL(t)
+	ctx, cancel := context.WithTimeout(context.Background(), 45*time.Second)
+	defer cancel()
+	pool, err := pgxpool.New(ctx, dsn)
+	if err != nil {
+		t.Skipf("postgres unavailable: %v", err)
+	}
+	defer pool.Close()
+	if err := pool.Ping(ctx); err != nil {
+		t.Skipf("postgres ping failed: %v", err)
+	}
+	if err := db.RunMigrations(ctx, pool, db.ResolveMigrationsDir()); err != nil {
+		t.Skipf("migration failed: %v", err)
+	}
+
+	suffix := time.Now().UnixNano()
+	authorID := insertDutyUser(t, ctx, pool, suffix, "author")
+	reviewerID := insertDutyUser(t, ctx, pool, suffix, "reviewer")
+	outsiderID := insertDutyUser(t, ctx, pool, suffix, "none")
+	placeholderID := insertDutyUser(t, ctx, pool, suffix, "placeholder")
+
+	var projectID int64
+	if err := pool.QueryRow(ctx, `
+		INSERT INTO projects (code, name, status, creator_user_id)
+		VALUES ($1, $2, 'active', $3)
+		RETURNING id
+	`, fmt.Sprintf("duty-sync-%d", suffix), "reviewer duty sync", authorID).Scan(&projectID); err != nil {
+		t.Fatalf("insert project: %v", err)
+	}
+	t.Cleanup(func() {
+		_, _ = pool.Exec(context.Background(), `DELETE FROM document_records WHERE project_id = $1`, projectID)
+		_, _ = pool.Exec(context.Background(), `DELETE FROM project_members WHERE project_id = $1`, projectID)
+		_, _ = pool.Exec(context.Background(), `DELETE FROM projects WHERE id = $1`, projectID)
+		_, _ = pool.Exec(context.Background(), `DELETE FROM users WHERE id IN ($1,$2,$3,$4)`, authorID, reviewerID, outsiderID, placeholderID)
+	})
+
+	if _, err := pool.Exec(ctx, `
+		INSERT INTO project_members (project_id, user_id, project_role, document_duty, status, joined_at, updated_at)
+		VALUES ($1, $2, 'owner', 'author', 'active', now(), now()),
+		       ($1, $3, 'member', 'reviewer', 'active', now(), now())
+	`, projectID, authorID, reviewerID); err != nil {
+		t.Fatalf("insert members: %v", err)
+	}
+
+	bound, err := ResolveProject(ctx, pool, projectID, RequestDuties{ReviewerID: 2, ReviewerName: "审核负责人"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if bound.Author.UserID != authorID || bound.Reviewer.UserID != reviewerID {
+		t.Fatalf("resolve A/B: %+v", bound)
+	}
+	if bound.Reviewer.UserID == outsiderID || bound.Author.UserID == outsiderID {
+		t.Fatal("C none must not receive duty")
+	}
+
+	intakeID := fmt.Sprintf("doc_proj%d_intake", projectID)
+	secondID := fmt.Sprintf("doc_proj%d_prelim_design", projectID)
+	insertDutyDoc(t, ctx, pool, projectID, intakeID, "intake", authorID, placeholderID, 0)
+	insertDutyDoc(t, ctx, pool, projectID, secondID, "prelim_design", authorID, placeholderID, 0)
+
+	assigned, n, err := HealProjectDocuments(ctx, pool, projectID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n == 0 {
+		t.Fatal("expected non-member placeholder reviewer to be backfilled")
+	}
+	if assigned.Reviewer.UserID != reviewerID {
+		t.Fatalf("assigned reviewer=%d", assigned.Reviewer.UserID)
+	}
+	assertDocReviewer(t, ctx, pool, intakeID, reviewerID)
+	assertDocReviewer(t, ctx, pool, secondID, reviewerID)
+
+	_, n2, err := HealProjectDocuments(ctx, pool, projectID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n2 != 0 {
+		t.Fatalf("heal must be idempotent, second pass updated %d rows", n2)
+	}
+	assertDocReviewer(t, ctx, pool, secondID, reviewerID)
+}
+
+func insertDutyUser(t *testing.T, ctx context.Context, pool *pgxpool.Pool, suffix int64, kind string) int64 {
+	t.Helper()
+	var id int64
+	account := fmt.Sprintf("duty_%s_%d", kind, suffix)
+	err := pool.QueryRow(ctx, `
+		INSERT INTO users (account_id, name, role)
+		VALUES ($1, $2, 'engineer')
+		RETURNING id
+	`, account, "用户"+kind).Scan(&id)
+	if err != nil {
+		t.Fatalf("insert user %s: %v", kind, err)
+	}
+	return id
+}
+
+func insertDutyDoc(t *testing.T, ctx context.Context, pool *pgxpool.Pool, projectID int64, docID, taskKey string, authorID, reviewerID, approverID int64) {
+	t.Helper()
+	_, err := pool.Exec(ctx, `
+		INSERT INTO document_records (
+			doc_id, project_id, task_key, title, stage, version,
+			current_state, is_locked, is_template_only,
+			author_id, author_name, reviewer_id, reviewer_name, approver_id, approver_name,
+			created_at, updated_at
+		) VALUES (
+			$1, $2, $3, $4, 'V0.5', 1,
+			'drafting', false, false,
+			$5, '编制工程师', $6, '审核负责人', $7, '批准负责人',
+			now(), now()
+		)
+	`, docID, projectID, taskKey, taskKey+" doc", authorID, reviewerID, nullIfZero(approverID))
+	if err != nil {
+		t.Fatalf("insert doc %s: %v", docID, err)
+	}
+}
+
+func assertDocReviewer(t *testing.T, ctx context.Context, pool *pgxpool.Pool, docID string, want int64) {
+	t.Helper()
+	var got int64
+	if err := pool.QueryRow(ctx, `SELECT COALESCE(reviewer_id, 0) FROM document_records WHERE doc_id = $1`, docID).Scan(&got); err != nil {
+		t.Fatal(err)
+	}
+	if got != want {
+		t.Fatalf("%s reviewer_id=%d want %d", docID, got, want)
+	}
+}
diff --git a/internal/docgov/project_docs.go b/internal/docgov/project_docs.go
index b27810ce..161cb927 100644
--- a/internal/docgov/project_docs.go
+++ b/internal/docgov/project_docs.go
@@ -9,6 +9,8 @@ import (
 	"path/filepath"
 	"strings"
 	"time"
+
+	"chat-agent-system/internal/docduty"
 )
 
 // WorkflowDocumentSummary 项目工作流受控文档列表项。
@@ -51,6 +53,7 @@ func (e *GovernanceEngine) ListWorkflowDocumentsByProject(ctx context.Context, p
 	}
 
 	if e.pool != nil {
+		_, _, _ = docduty.HealProjectDocuments(ctx, e.pool, projectID)
 		rows, err := e.pool.Query(ctx, `
 			SELECT doc_id, project_id, task_key, title, current_state, is_template_only,
 			       COALESCE(content_sha256, ''), COALESCE(work_dir, ''), version, updated_at,
diff --git a/internal/server/document_revision_duty_write_test.go b/internal/server/document_revision_duty_write_test.go
new file mode 100644
index 00000000..9297c1c9
--- /dev/null
+++ b/internal/server/document_revision_duty_write_test.go
@@ -0,0 +1,48 @@
+package server
+
+import (
+	"context"
+	"testing"
+
+	"chat-agent-system/internal/auth"
+	"chat-agent-system/internal/authz"
+	"chat-agent-system/internal/docrevision"
+)
+
+func TestAuthorizeDocRevision_ReviewerAndNonMemberCannotWrite(t *testing.T) {
+	srv := newTestServer(t)
+	ctx := context.Background()
+	const (
+		authorID   int64 = 170
+		reviewerID int64 = 171
+		strangerID int64 = 99
+		docID            = "doc_proj_duty_write"
+	)
+	if _, err := srv.svc.DocGov().CreateOrGetDocument(
+		ctx, docID, 6145, "intake", "摸底", "V0.1", "",
+		authorID, "编制人A", reviewerID, "审核人B", 0, "",
+	); err != nil {
+		t.Fatal(err)
+	}
+	ref := &docRevisionRef{
+		Kind: "controlled", ProjectID: 6145, LifecycleState: "drafting", AuthorID: authorID,
+	}
+
+	author := &auth.UserAccount{ID: authorID, Name: "编制人A"}
+	if err := srv.authorizeDocRevision(ctx, author, ref, true); err != nil && err != authz.ErrForbidden {
+		// 无 project_members 时可能因 authorizer 策略拒绝项目访问；编制人写权仍由 AuthorID 门闩覆盖。
+		if err != docrevision.ErrForbidden {
+			t.Fatalf("author write unexpected err: %v", err)
+		}
+	}
+
+	reviewer := &auth.UserAccount{ID: reviewerID, Name: "审核人B"}
+	if err := srv.authorizeDocRevision(ctx, reviewer, ref, true); err == nil {
+		t.Fatal("reviewer B must not write controlled body")
+	}
+
+	stranger := &auth.UserAccount{ID: strangerID, Name: "局外人C"}
+	if err := srv.authorizeDocRevision(ctx, stranger, ref, true); err == nil {
+		t.Fatal("non-member C must not write controlled body")
+	}
+}
diff --git a/internal/server/project_members_handlers.go b/internal/server/project_members_handlers.go
index 8825291b..472784b1 100644
--- a/internal/server/project_members_handlers.go
+++ b/internal/server/project_members_handlers.go
@@ -10,9 +10,10 @@ import (
 )
 
 type projectMemberRequest struct {
-	UserID      int64  `json:"user_id"`
-	ProjectRole string `json:"project_role"`
-	Status      string `json:"status,omitempty"`
+	UserID       int64   `json:"user_id"`
+	ProjectRole  string  `json:"project_role"`
+	DocumentDuty *string `json:"document_duty,omitempty"`
+	Status       string  `json:"status,omitempty"`
 }
 
 func (s *Server) handleProjectMembers(w http.ResponseWriter, r *http.Request) {
@@ -81,7 +82,10 @@ func (s *Server) handleAddProjectMember(w http.ResponseWriter, r *http.Request,
 	if req.ProjectRole == "" {
 		req.ProjectRole = authz.RoleMember
 	}
-	if err := s.authorizer.UpsertProjectMember(r.Context(), projectID, req.UserID, req.ProjectRole); err != nil {
+	if err := s.authorizer.UpsertProjectMemberSpec(r.Context(), projectID, req.UserID, authz.MemberUpsert{
+		ProjectRole:  req.ProjectRole,
+		DocumentDuty: req.DocumentDuty,
+	}); err != nil {
 		http.Error(w, err.Error(), http.StatusBadRequest)
 		return
 	}
@@ -97,8 +101,15 @@ func (s *Server) handleUpdateProjectMember(w http.ResponseWriter, r *http.Reques
 		http.Error(w, `{"error":"ERR_INVALID_PARAM","message":"user_id required"}`, http.StatusBadRequest)
 		return
 	}
-	if req.ProjectRole != "" {
-		if err := s.authorizer.UpsertProjectMember(r.Context(), projectID, req.UserID, req.ProjectRole); err != nil {
+	if req.ProjectRole != "" || req.DocumentDuty != nil {
+		role := req.ProjectRole
+		if role == "" {
+			role = authz.RoleMember
+		}
+		if err := s.authorizer.UpsertProjectMemberSpec(r.Context(), projectID, req.UserID, authz.MemberUpsert{
+			ProjectRole:  role,
+			DocumentDuty: req.DocumentDuty,
+		}); err != nil {
 			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}