feat: replace in_namespace relation with ownership-based namespace membership

Remove the in_namespace edge relation. A node now belongs to a namespace if that
namespace has has_ownership on it. This simplifies the model: namespace membership
is determined by the ownership chain rather than a separate relation type.

Changes:
- Remove RelInNamespace constant
- Add Namespace fields to AddInput, UpdateInput, and ListFilter
- Update Add() to resolve namespace from input and assign it as owner
- Update List() to filter by namespace ownership instead of in_namespace edges
- Update() can now transfer nodes between namespaces via ownership transfer
- Remove in_namespace self-references from ensureNamespace/ensureGlobalNamespace

The ownership chain now fully describes both permissions and namespace membership,
reducing redundancy. All tests pass with the new model.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

src/cmd/add.go

@@ -43,7 +43,7 @@ var addCmd = &cobra.Command{
 			input.Rels = append(input.Rels, service.RelInput{Type: models.RelType("_prio::" + cPrio), Target: ""})
 		}
 		if cNamespace != "" {
-			input.Rels = append(input.Rels, service.RelInput{Type: models.RelInNamespace, Target: cNamespace})
+			input.Namespace = cNamespace
 		}
 		if cAssignee != "" {
 			input.Rels = append(input.Rels, service.RelInput{Type: models.RelAssignee, Target: cAssignee})

src/cmd/list.go

@@ -46,7 +46,7 @@ var listCmd = &cobra.Command{
 			filter.Rels = append(filter.Rels, service.RelInput{Type: models.RelType("_type::" + lType), Target: ""})
 		}
 		if lNamespace != "" {
-			filter.Rels = append(filter.Rels, service.RelInput{Type: models.RelInNamespace, Target: lNamespace})
+			filter.Namespace = lNamespace
 		}
 		if lAssignee != "" {
 			filter.Rels = append(filter.Rels, service.RelInput{Type: models.RelAssignee, Target: lAssignee})

src/cmd/output.go

@@ -49,7 +49,7 @@ var (
 		"low":    {" ", "low", cDim},
 		"":       {" ", "n/a", cDim},
 	}
-	relIcons    = map[string]string{"blocks": "\uf068", "subtask": "\uf0da", "related": "\uf0c1", "assignee": "\uf007", "in_namespace": "\uf07b"}
+	relIcons = map[string]string{"blocks": "\uf068", "subtask": "\uf0da", "related": "\uf0c1", "assignee": "\uf007"}
 	prioRanks   = map[string]int{"high": 3, "medium": 2, "low": 1}
 	statusRanks = map[string]int{"open": 2, "": 1, "done": 0}
 )
@@ -94,24 +94,12 @@ func PrintNodes(w io.Writer, svc service.NodeService, nodes []*models.Node, json
 	})
 
 	for _, n := range nodes {
-		n_rels := n.Relations
+		fmt.Fprintf(w, "  %s %s %s %s %s %s",
-		ns_rel_node_ids := n_rels[string(models.RelInNamespace)]
-		ns_rel_node_titles := make([]string, 0, len(ns_rel_node_ids))
-		for _, id := range ns_rel_node_ids {
-			ns_rel_node, err := svc.GetByID(id)
-			if err != nil {
-				ns_rel_node_titles = append(ns_rel_node_titles, id)
-				continue
-			}
-			ns_rel_node_titles = append(ns_rel_node_titles, ns_rel_node.Title)
-		}
-		fmt.Fprintf(w, "  %s %s %s %s %s %s %s",
 			cDim.Sprint(n.ID),
 			render(prioRM, n.GetProperty("prio"), true),
 			render(statusRM, n.GetProperty("status"), true),
 			render(typeRM, n.GetProperty("type"), true),
 			cTitle.Sprint(truncate(n.Title, 80)),
-			cDim.Sprint("["+strings.Join(ns_rel_node_titles, ",")+"]"),
 			dueDateShort(n.DueDate),
 		)
 		tags := n.GetDisplayTags()

src/cmd/update.go

@@ -61,7 +61,7 @@ var updateCmd = &cobra.Command{
 			input.AddRels = append(input.AddRels, service.RelInput{Type: models.RelType("_prio::" + uPrio), Target: ""})
 		}
 		if cmd.Flags().Changed("namespace") {
-			input.AddRels = append(input.AddRels, service.RelInput{Type: models.RelInNamespace, Target: uNamespace})
+			input.Namespace = &uNamespace
 		}
 		if cmd.Flags().Changed("assignee") {
 			input.AddRels = append(input.AddRels, service.RelInput{Type: models.RelAssignee, Target: uAssignee})

src/e2e/e2e_crud_test.go

@@ -33,9 +33,6 @@ func TestCRUD(t *testing.T) {
 		if len(n.Relations["created"]) == 0 {
 			t.Error("expected created relation to be set")
 		}
-		if len(n.Relations["in_namespace"]) == 0 {
-			t.Error("expected in_namespace relation to be set")
-		}
 		if n.CreatedAt == "" || n.UpdatedAt == "" {
 			t.Error("expected timestamps to be set")
 		}
@@ -73,9 +70,6 @@ func TestCRUD(t *testing.T) {
 		if n.Content != "some body" {
 			t.Errorf("content: want %q, got %q", "some body", n.Content)
 		}
-		if len(n.Relations["in_namespace"]) == 0 {
-			t.Error("expected in_namespace relation")
-		}
 		if len(n.Relations["assignee"]) == 0 {
 			t.Error("expected assignee relation")
 		}

src/e2e/e2e_permissions_test.go

@@ -168,10 +168,6 @@ func TestNamespaceExplicitCreate(t *testing.T) {
 
 	nsNode := env.parseNode(env.mustAx("add", "myworkspace", "--type", "namespace", "--json"))
 
-	if !nsNode.HasRelation("in_namespace", nsNode.ID) {
-		t.Errorf("expected namespace to have in_namespace pointing to itself, got relations: %v", nsNode.Relations)
-	}
-
 	users := env.parseNodes(env.mustAx("list", "--type", "user", "--json"))
 	var userNode *NodeResponse
 	for i := range users {

src/models/node.go

@@ -89,7 +89,7 @@ func (n *Node) AddRelation(relType RelType, target string) {
 	if n.Relations == nil {
 		n.Relations = make(map[string][]string)
 	}
-	if relType == RelAssignee || relType == RelCreated || relType == RelInNamespace {
+	if relType == RelAssignee || relType == RelCreated {
 		n.Relations[string(relType)] = []string{target}
 		return
 	}

src/models/rel_type.go

@@ -13,7 +13,6 @@ const (
 	RelRelated  RelType = "related"
 	RelCreated  RelType = "created"
 	RelAssignee RelType = "assignee"
-	RelInNamespace RelType = "in_namespace"
 	RelMentions RelType = "mentions"
 
 	// Permission rels (subject → object). Levels are inclusive and transitive.

src/serve/server.go

@@ -77,7 +77,7 @@ func (s *server) listNodes(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 	if v := q.Get("namespace"); v != "" {
-		filter.Rels = append(filter.Rels, service.RelInput{Type: models.RelInNamespace, Target: v})
+		filter.Namespace = v
 	}
 	if v := q.Get("assignee"); v != "" {
 		filter.Rels = append(filter.Rels, service.RelInput{Type: models.RelAssignee, Target: v})

src/service/api_client.go

@@ -72,6 +72,9 @@ func (c *apiClient) GetByID(id string) (*models.Node, error) {
 
 func (c *apiClient) List(filter ListFilter) ([]*models.Node, error) {
 	q := url.Values{}
+	if filter.Namespace != "" {
+		q.Set("namespace", filter.Namespace)
+	}
 	for _, r := range filter.Rels {
 		if r.Target == "" {
 			q.Add("rel", string(r.Type))

src/service/node_service.go

@@ -37,17 +37,20 @@ type AddInput struct {
 	Title     string
 	Content   string
 	DueDate   string
+	Namespace string // namespace name or ID; defaults to the user's personal namespace
 	Rels      []RelInput
 }
 
 // UpdateInput describes changes to apply to an existing node.
 // AddRels and RemoveRels accept both tag rels (Target == "") and edge rels.
 // Setting _status::done in AddRels is rejected when the node has open blockers.
-// Adding assignee or in_namespace rels replaces the previous single target.
+// Adding an assignee rel replaces the previous single target.
+// Setting Namespace transfers ownership from the current namespace to the new one.
 type UpdateInput struct {
 	Title      *string
 	Content    *string
 	DueDate    *string // nil = no change; pointer to "" = clear due date
+	Namespace  *string // nil = no change; namespace name or ID to move node into
 	AddRels    []RelInput
 	RemoveRels []RelInput
 }
@@ -56,6 +59,7 @@ type UpdateInput struct {
 // Tag filters (Target == "") match by rel_name prefix.
 // Edge filters (Target != "") are resolved to node IDs.
 type ListFilter struct {
+	Namespace  string // when non-empty, only return nodes owned by this namespace
 	Rels       []RelInput
 	HasDueDate bool // when true, only return nodes that have a due date set
 	DueWithin  *int // when non-nil, only return nodes due within this many days (includes overdue)

src/service/node_service_impl.go

@@ -75,7 +75,7 @@ const (
 // namespaces are globally readable and any node can reference them.
 func isReferenceRel(t models.RelType) bool {
 	switch t {
-	case models.RelAssignee, models.RelCreated, models.RelMentions, models.RelInNamespace:
+	case models.RelAssignee, models.RelCreated, models.RelMentions:
 		return true
 	}
 	return false
@@ -208,6 +208,28 @@ func (s *nodeServiceImpl) GetByID(id string) (*models.Node, error) {
 }
 
 func (s *nodeServiceImpl) List(filter ListFilter) ([]*models.Node, error) {
+	// Resolve namespace filter to owned node IDs.
+	var nsOwnedIDs map[string]bool
+	if filter.Namespace != "" {
+		nsID, _ := s.resolveIDByNameAndType(s.store, filter.Namespace, "namespace")
+		if nsID == "" {
+			if exists, _ := s.store.NodeExists(filter.Namespace); exists {
+				nsID = filter.Namespace
+			}
+		}
+		if nsID == "" {
+			return nil, nil // namespace not found
+		}
+		nsNode, err := s.store.GetNode(nsID)
+		if err != nil {
+			return nil, nil
+		}
+		nsOwnedIDs = make(map[string]bool)
+		for _, ownedID := range nsNode.Relations[string(models.RelHasOwnership)] {
+			nsOwnedIDs[ownedID] = true
+		}
+	}
+
 	var storeFilters []*models.Rel
 	for _, ri := range filter.Rels {
 		if ri.Target == "" {
@@ -230,9 +252,13 @@ func (s *nodeServiceImpl) List(filter ListFilter) ([]*models.Node, error) {
 	}
 	var result []*models.Node
 	for _, n := range nodes {
-		if pc.canRead(n.ID) {
+		if !pc.canRead(n.ID) {
-			result = append(result, n)
+			continue
 		}
+		if nsOwnedIDs != nil && !nsOwnedIDs[n.ID] {
+			continue
+		}
+		result = append(result, n)
 	}
 
 	if filter.HasDueDate || filter.DueWithin != nil {
@@ -323,13 +349,6 @@ func (s *nodeServiceImpl) Add(input AddInput) (*models.Node, error) {
 		}
 	}
 
-	hasNamespace := false
-	for _, ri := range input.Rels {
-		if ri.Type == models.RelInNamespace && ri.Target != "" {
-			hasNamespace = true
-		}
-	}
-
 	dueDate, err := parseDueDate(input.DueDate)
 	if err != nil {
 		return nil, err
@@ -364,9 +383,8 @@ func (s *nodeServiceImpl) Add(input AddInput) (*models.Node, error) {
 			}
 		}
 
-		// Edge rels. Track the namespace the node is placed in for ownership.
+		// Edge rels.
 		hasCreated := false
-		var actualNsID string
 		for _, ri := range input.Rels {
 			if ri.Target == "" {
 				continue // already stored as tag
@@ -378,9 +396,6 @@ func (s *nodeServiceImpl) Add(input AddInput) (*models.Node, error) {
 			if err != nil {
 				return err
 			}
-			if ri.Type == models.RelInNamespace {
-				actualNsID = resolved
-			}
 			if ri.Type == models.RelHasOwnership {
 				// Ownership transfer: remove existing owner of the target.
 				existingOwners, _ := st.FindNodes([]*models.Rel{{Type: models.RelHasOwnership, Target: resolved}})
@@ -393,18 +408,6 @@ func (s *nodeServiceImpl) Add(input AddInput) (*models.Node, error) {
 			}
 		}
 
-		// Default namespace.
-		if !hasNamespace {
-			nsID, err := s.resolveNamespaceRef(st, s.userID)
-			if err != nil {
-				return err
-			}
-			if err := st.AddRel(id, string(models.RelInNamespace), nsID); err != nil {
-				return err
-			}
-			actualNsID = nsID
-		}
-
 		// Default created.
 		if !hasCreated {
 			userID, err := s.resolveUserRef(st, s.userID)
@@ -417,39 +420,30 @@ func (s *nodeServiceImpl) Add(input AddInput) (*models.Node, error) {
 		}
 
 		// Grant ownership of the new node.
-		// Namespace nodes are owned by their creator. All other nodes are owned
+		// Namespace nodes are owned by their creator (user node).
-		// by the namespace they belong to — the user retains transitive ownership
+		// All other nodes are owned by the namespace they belong to — the user
-		// through the namespace's own ownership chain (e.g. user→owns→default-ns→owns→node).
+		// retains transitive ownership through the namespace's own ownership chain
+		// (e.g. user→has_ownership→default-ns→has_ownership→node).
 		creatorID, err := s.resolveUserRef(st, s.userID)
 		if err != nil {
 			return err
 		}
 		ownerID := creatorID
-		if tmp.GetProperty("type") != "namespace" && actualNsID != "" {
+		if tmp.GetProperty("type") != "namespace" {
-			ownerID = actualNsID
+			nsRef := input.Namespace
+			if nsRef == "" {
+				nsRef = s.userID
+			}
+			nsID, err := s.resolveNamespaceRef(st, nsRef)
+			if err != nil {
+				return err
+			}
+			ownerID = nsID
 		}
 		if err := st.AddRel(ownerID, string(models.RelHasOwnership), id); err != nil {
 			return err
 		}
 
-		// Namespace bootstrap: when creating a namespace node directly, apply the
-		// same setup as ensureNamespace — self in_namespace and creator ownership.
-		if tmp.GetProperty("type") == "namespace" {
-			if !hasNamespace {
-				// Replace the default namespace rel (user's ns) with self-reference.
-				userNsID, _ := s.resolveIDByNameAndType(st, s.userID, "namespace")
-				if userNsID != "" {
-					if err := st.RemoveRel(id, string(models.RelInNamespace), userNsID); err != nil {
-						return err
-					}
-				}
-				if err := st.AddRel(id, string(models.RelInNamespace), id); err != nil {
-					return err
-				}
-			}
-			// Creator already gets ownership via the block above; nothing more to do.
-		}
-
 		return nil
 	})
 	if err != nil {
@@ -470,8 +464,8 @@ func (s *nodeServiceImpl) Update(id string, input UpdateInput) (*models.Node, er
 		return nil, err
 	}
 
-	// Field/tag changes and rel removals require can_write on the node.
+	// Field/tag changes, rel removals, and namespace change require can_write on the node.
-	needsWrite := input.Title != nil || input.Content != nil || input.DueDate != nil
+	needsWrite := input.Title != nil || input.Content != nil || input.DueDate != nil || input.Namespace != nil
 	for _, ri := range input.AddRels {
 		if ri.Target == "" {
 			needsWrite = true
@@ -619,7 +613,7 @@ func (s *nodeServiceImpl) Update(id string, input UpdateInput) (*models.Node, er
 				return err
 			}
 			// Single-value relations replace the previous target.
-			if ri.Type == models.RelAssignee || ri.Type == models.RelInNamespace {
+			if ri.Type == models.RelAssignee {
 				for _, oldTgt := range currentRels[string(ri.Type)] {
 					if err := st.RemoveRel(id, string(ri.Type), oldTgt); err != nil {
 						return err
@@ -651,6 +645,24 @@ func (s *nodeServiceImpl) Update(id string, input UpdateInput) (*models.Node, er
 			}
 		}
 
+		// Namespace change: transfer ownership from the current namespace to the new one.
+		if input.Namespace != nil {
+			newNsID, err := s.resolveNamespaceRef(st, *input.Namespace)
+			if err != nil {
+				return err
+			}
+			// Remove ownership from any current namespace owner.
+			currentOwners, _ := st.FindNodes([]*models.Rel{{Type: models.RelHasOwnership, Target: id}})
+			for _, owner := range currentOwners {
+				if owner.GetProperty("type") == "namespace" {
+					st.RemoveRel(owner.ID, string(models.RelHasOwnership), id) //nolint:errcheck
+				}
+			}
+			if err := st.AddRel(newNsID, string(models.RelHasOwnership), id); err != nil {
+				return err
+			}
+		}
+
 		return nil
 	})
 	if err != nil {
@@ -770,8 +782,6 @@ func (s *nodeServiceImpl) resolveRelTarget(st store.GraphStore, ri RelInput) (st
 	switch ri.Type {
 	case models.RelAssignee, models.RelCreated, models.RelMentions:
 		return s.resolveUserRef(st, ri.Target)
-	case models.RelInNamespace:
-		return s.resolveNamespaceRef(st, ri.Target)
 	default:
 		// Permission rels and all other edge rels expect raw node IDs.
 		return ri.Target, nil
@@ -788,8 +798,6 @@ func (s *nodeServiceImpl) lookupRelTarget(relType models.RelType, target string)
 	switch relType {
 	case models.RelAssignee, models.RelCreated, models.RelMentions:
 		nodeType = "user"
-	case models.RelInNamespace:
-		nodeType = "namespace"
 	default:
 		// Permission rels and other edge rels use raw node IDs.
 		return "", false
@@ -843,9 +851,6 @@ func (s *nodeServiceImpl) ensureGlobalNamespace(st store.GraphStore) (string, er
 	if err := st.AddRel(id, "_type::namespace", ""); err != nil {
 		return "", err
 	}
-	if err := st.AddRel(id, string(models.RelInNamespace), id); err != nil {
-		return "", err
-	}
 	// Self-owned so no single user controls it.
 	if err := st.AddRel(id, string(models.RelHasOwnership), id); err != nil {
 		return "", err
@@ -916,9 +921,6 @@ func (s *nodeServiceImpl) ensureNamespace(st store.GraphStore, name string) (str
 	if err := st.AddRel(id, "_type::namespace", ""); err != nil {
 		return "", err
 	}
-	if err := st.AddRel(id, string(models.RelInNamespace), id); err != nil {
-		return "", err
-	}
 	userID, err := s.resolveUserRef(st, s.userID)
 	if err != nil {
 		return "", err