feat: shift+drag to create one-way links on admin map

8 files changed, 183 insertions, 89 deletions

diff --git a/building_guide/admin.md b/building_guide/admin.md
index fbe15d5..023fae1 100644
--- a/building_guide/admin.md
+++ b/building_guide/admin.md
@@ -239,7 +239,9 @@ even across sessions.
 The map page (`/`) is the main navigation hub:
 - Rooms are displayed as colored nodes on a 3D grid, connected by links (bars for two-way, arrows for one-way, X for blocked).
 - Click a room node to edit its properties (name, description, color, exits, objects, mobs, spawns).
-- Drag connections between rooms to create or relink exits.
+- **Drag** connections between rooms to create reciprocal exits. **Shift+drag** to create a one-way exit (only the exit from the source room is written; the target room is not modified).
+- **Right-drag** between rooms to delete the exit (full reciprocal; the sidebar Exits tab has a "Remove reverse" button to convert a two-way exit to one-way).
+- If deleting an exit severs a room from the seed grid, the room moves to the "Disconnected Rooms" sidebar. Relink it via the Exits tab "Add" form with its ID and direction.
 - Right-click (or long-press) a room to delete it or access advanced options.
 - The map uses the same BFS-based grid layout as the in-game map, showing all rooms on the current z-plane.
 - Up/down links are shown with special glyphs when connecting rooms on different z-levels.
diff --git a/data/.admin_history.json b/data/.admin_history.json
index 6926f3a..ada2f83 100644
--- a/data/.admin_history.json
+++ b/data/.admin_history.json
@@ -1 +1 @@
-{"history":[{"time":"2026-07-05T22:17:30-04:00","description":"unlink 99999202 down 99999200","file_path":"data/rooms/example_unused/agility2/99999202.yaml","old_content":"name: \"Ventilation Shaft - Coolant Pipe Walkway\"\ndescription: \"A narrow coolant pipe stretches across a dark chasm. Condensation drips from its surface, making it slick. Far below, you can hear the distant hum of machinery.\"\non_enter:\n  - message: \"Type 'balance' to cross the pipe.\"\nexits:\n  down:\n    room: 99999200\n    blocked_message: \"\"\n","new_content":"id: 99999202\nname: Ventilation Shaft - Coolant Pipe Walkway\ncolor: \"\"\ndescription:\n  - text: A narrow coolant pipe stretches across a dark chasm. Condensation drips from its surface, making it slick. Far below, you can hear the distant hum of machinery.\nexits: {}\nobjects: []\nitem_spawns: []\nmobs: []\non_enter:\n  - message: Type 'balance' to cross the pipe.\n    condition: null\n    delay: 0\n    set_flags: {}\n    set_player_flags: {}\n    broadcast: \"\"\n    broadcast_global: \"\"\n    spawn_mob: null\n    despawn_mob: \"\"\n    give_item: \"\"\n    take_item: \"\"\n    teleport: 0\n    heal: 0\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","is_delete":false,"is_create":false},{"time":"2026-07-05T22:17:30-04:00","description":"unlink 99999200 up 99999202 (reverse)","file_path":"data/rooms/example_unused/agility2/99999200.yaml","old_content":"name: \"Agility Training Grounds\"\ndescription: \"A cavernous space beneath the asteroid's surface, repurposed as a training facility. Scaffolding, pipes, and platforms fill the chamber. Signs point to three courses of increasing difficulty: {33}Ventilation Shaft{/} (beginner), {214}Rooftop{/} (intermediate), and {196}Reactor{/} (advanced).\"\nexits:\n  south: 9999917\n  north: 99999201\n  east: 99999210\n  west: 99999220\n","new_content":"id: 99999200\nname: Agility Training Grounds\ncolor: \"\"\ndescription:\n  - text: 'A cavernous space beneath the asteroid''s surface, repurposed as a training facility. Scaffolding, pipes, and platforms fill the chamber. Signs point to three courses of increasing difficulty: {33}Ventilation Shaft{/} (beginner), {214}Rooftop{/} (intermediate), and {196}Reactor{/} (advanced).'\nexits:\n  east:\n    room: 99999210\n  north:\n    room: 99999201\n  south:\n    room: 9999917\n  west:\n    room: 99999220\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","is_delete":false,"is_create":false}],"redo":null}
\ No newline at end of file
+{"history":[{"time":"2026-07-06T17:37:10-04:00","description":"create room 1005","file_path":"data/rooms/intro/1005.yaml","old_content":"","new_content":"exits:\n  south: 2001\nid: 1005\nname: 'Room #1005'\n","is_delete":false,"is_create":true,"extra_files":[{"file_path":"data/rooms/intro/2001.yaml","old_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  north:\n    room: 1005\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n"}]},{"time":"2026-07-06T17:37:13-04:00","description":"unlink 2001 north 1005","file_path":"data/rooms/intro/2001.yaml","old_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  north:\n    room: 1005\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","is_delete":false,"is_create":false},{"time":"2026-07-06T17:37:13-04:00","description":"unlink 1005 south 2001 (reverse)","file_path":"data/rooms/intro/1005.yaml","old_content":"exits:\n  south: 2001\nid: 1005\nname: 'Room #1005'\n","new_content":"id: 1005\nname: 'Room #1005'\ncolor: \"\"\ndescription: []\nexits: {}\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","is_delete":false,"is_create":false},{"time":"2026-07-06T17:37:16-04:00","description":"create room 1006","file_path":"data/rooms/intro/1006.yaml","old_content":"","new_content":"exits:\n  south: 2001\nid: 1006\nname: 'Room #1006'\n","is_delete":false,"is_create":true,"extra_files":[{"file_path":"data/rooms/intro/2001.yaml","old_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  north:\n    room: 1006\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n"}]},{"time":"2026-07-06T17:37:23-04:00","description":"unlink 2001 north 1006","file_path":"data/rooms/intro/2001.yaml","old_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  north:\n    room: 1006\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","is_delete":false,"is_create":false},{"time":"2026-07-06T17:37:23-04:00","description":"unlink 1006 south 2001 (reverse)","file_path":"data/rooms/intro/1006.yaml","old_content":"exits:\n  south: 2001\nid: 1006\nname: 'Room #1006'\n","new_content":"id: 1006\nname: 'Room #1006'\ncolor: \"\"\ndescription: []\nexits: {}\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","is_delete":false,"is_create":false},{"time":"2026-07-06T17:39:43-04:00","description":"create room 1007","file_path":"data/rooms/intro/1007.yaml","old_content":"","new_content":"exits:\n  south: 2001\nid: 1007\nname: 'Room #1007'\n","is_delete":false,"is_create":true,"extra_files":[{"file_path":"data/rooms/intro/2001.yaml","old_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  north:\n    room: 1007\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n"}]},{"time":"2026-07-06T17:39:46-04:00","description":"create room 1008","file_path":"data/rooms/intro/1008.yaml","old_content":"","new_content":"exits:\n  south: 1007\nid: 1008\nname: 'Room #1008'\n","is_delete":false,"is_create":true,"extra_files":[{"file_path":"data/rooms/intro/1007.yaml","old_content":"exits:\n  south: 2001\nid: 1007\nname: 'Room #1007'\n","new_content":"id: 1007\nname: 'Room #1007'\ncolor: \"\"\ndescription: []\nexits:\n  north:\n    room: 1008\n  south:\n    room: 2001\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n"}]},{"time":"2026-07-06T17:39:49-04:00","description":"create room 1009","file_path":"data/rooms/intro/1009.yaml","old_content":"","new_content":"exits:\n  south: 1008\nid: 1009\nname: 'Room #1009'\n","is_delete":false,"is_create":true,"extra_files":[{"file_path":"data/rooms/intro/1008.yaml","old_content":"exits:\n  south: 1007\nid: 1008\nname: 'Room #1008'\n","new_content":"id: 1008\nname: 'Room #1008'\ncolor: \"\"\ndescription: []\nexits:\n  north:\n    room: 1009\n  south:\n    room: 1007\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n"}]},{"time":"2026-07-06T17:39:57-04:00","description":"delete room 1009 (cleaned 1 exits)","file_path":"data/rooms/intro/1009.yaml","old_content":"exits:\n  south: 1008\nid: 1009\nname: 'Room #1009'\n","new_content":"","is_delete":true,"is_create":false,"extra_files":[{"file_path":"data/rooms/intro/1008.yaml","old_content":"id: 1008\nname: 'Room #1008'\ncolor: \"\"\ndescription: []\nexits:\n  north:\n    room: 1009\n  south:\n    room: 1007\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"id: 1008\nname: 'Room #1008'\ncolor: \"\"\ndescription: []\nexits:\n  south:\n    room: 1007\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n"}]},{"time":"2026-07-06T17:39:58-04:00","description":"delete room 1008 (cleaned 1 exits)","file_path":"data/rooms/intro/1008.yaml","old_content":"id: 1008\nname: 'Room #1008'\ncolor: \"\"\ndescription: []\nexits:\n  south:\n    room: 1007\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"","is_delete":true,"is_create":false,"extra_files":[{"file_path":"data/rooms/intro/1007.yaml","old_content":"id: 1007\nname: 'Room #1007'\ncolor: \"\"\ndescription: []\nexits:\n  north:\n    room: 1008\n  south:\n    room: 2001\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"id: 1007\nname: 'Room #1007'\ncolor: \"\"\ndescription: []\nexits:\n  south:\n    room: 2001\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n"}]},{"time":"2026-07-06T17:39:59-04:00","description":"delete room 1007 (cleaned 1 exits)","file_path":"data/rooms/intro/1007.yaml","old_content":"id: 1007\nname: 'Room #1007'\ncolor: \"\"\ndescription: []\nexits:\n  south:\n    room: 2001\nobjects: []\nitem_spawns: []\nmobs: []\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"","is_delete":true,"is_create":false,"extra_files":[{"file_path":"data/rooms/intro/2001.yaml","old_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  north:\n    room: 1007\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n","new_content":"id: 2001\nname: Test Room\ncolor: \"\"\ndescription:\n  - text: It's a test room\nexits:\n  east:\n    room: 2002\n  south:\n    room: 2006\n  southeast:\n    room: 2005\n  west:\n    room: 1001\nobjects:\n  - name: hidden guy\n    hidden: true\n    description:\n      - text: YOU FOUND HIM\n  - id: tree\nitem_spawns:\n  - id: bronze_axe\n    quantity: 1\n    respawn_ticks: 1\n  - id: pot_of_flour\n    quantity: 1\n    respawn_ticks: 1\n  - id: bucket_of_water\n    quantity: 1\n    respawn_ticks: 1\nmobs:\n  - id: man\n  - id: flight_attendant_copy\non_enter: []\nhazard: \"\"\nblock_transport: false\ntriggers: []\n"}]}],"redo":null}
\ No newline at end of file
diff --git a/data/rooms/intro/1005.yaml b/data/rooms/intro/1005.yaml
new file mode 100644
index 0000000..faf82e3
--- /dev/null
+++ b/data/rooms/intro/1005.yaml
@@ -0,0 +1,12 @@
+id: 1005
+name: 'Room #1005'
+color: ""
+description: []
+exits: {}
+objects: []
+item_spawns: []
+mobs: []
+on_enter: []
+hazard: ""
+block_transport: false
+triggers: []
diff --git a/data/rooms/intro/1006.yaml b/data/rooms/intro/1006.yaml
new file mode 100644
index 0000000..5a87adb
--- /dev/null
+++ b/data/rooms/intro/1006.yaml
@@ -0,0 +1,12 @@
+id: 1006
+name: 'Room #1006'
+color: ""
+description: []
+exits: {}
+objects: []
+item_spawns: []
+mobs: []
+on_enter: []
+hazard: ""
+block_transport: false
+triggers: []
diff --git a/internal/admin/api_rooms.go b/internal/admin/api_rooms.go
index 448503d..b5353c2 100644
--- a/internal/admin/api_rooms.go
+++ b/internal/admin/api_rooms.go
@@ -415,19 +415,20 @@ func (s *AdminServer) handleRoomLink(w http.ResponseWriter, r *http.Request) {
 	switch r.Method {
 	case http.MethodPost:
 		var body struct {
-			From int    `json:"from"`
-			To   int    `json:"to"`
-			Dir  string `json:"dir"`
+			From   int    `json:"from"`
+			To     int    `json:"to"`
+			Dir    string `json:"dir"`
+			OneWay bool   `json:"oneway"`
 		}
 		if err := readJSON(r, &body); err != nil || body.From <= 0 || body.To <= 0 {
-			writeJSON(w, map[string]any{"error": "invalid body, need from and to"})
+			writeJSONError(w, "invalid body, need from and to", http.StatusBadRequest)
 			return
 		}
 
 		roomA, errA := s.world.LoadRoom(body.From)
 		roomB, errB := s.world.LoadRoom(body.To)
 		if errA != nil || errB != nil {
-			writeJSON(w, map[string]any{"error": "one or both rooms not found"})
+			writeJSONError(w, "one or both rooms not found", http.StatusBadRequest)
 			return
 		}
 
@@ -437,7 +438,7 @@ func (s *AdminServer) handleRoomLink(w http.ResponseWriter, r *http.Request) {
 			if opp, ok := world.OppositeExit[dir]; ok {
 				oppDir = opp
 			} else {
-				writeJSON(w, map[string]any{"error": "invalid direction: " + body.Dir})
+				writeJSONError(w, "invalid direction: "+body.Dir, http.StatusBadRequest)
 				return
 			}
 		} else {
@@ -453,11 +454,11 @@ func (s *AdminServer) handleRoomLink(w http.ResponseWriter, r *http.Request) {
 			cA, okA := grid.Coord[body.From]
 			cB, okB := grid.Coord[body.To]
 			if !okA || !okB {
-				writeJSON(w, map[string]any{"error": "one or both rooms are not reachable from the seed room"})
+				writeJSONError(w, "one or both rooms are not reachable from the seed room", http.StatusBadRequest)
 				return
 			}
 			if cA[2] != cB[2] {
-				writeJSON(w, map[string]any{"error": "rooms must be on same z-level"})
+				writeJSONError(w, "rooms must be on same z-level", http.StatusBadRequest)
 				return
 			}
 			dx, dy := cB[0]-cA[0], cB[1]-cA[1]
@@ -469,7 +470,7 @@ func (s *AdminServer) handleRoomLink(w http.ResponseWriter, r *http.Request) {
 				}
 			}
 			if dir == "" {
-				writeJSON(w, map[string]any{"error": "rooms are not adjacent"})
+				writeJSONError(w, "rooms are not adjacent", http.StatusBadRequest)
 				return
 			}
 		}
@@ -491,6 +492,21 @@ func (s *AdminServer) handleRoomLink(w http.ResponseWriter, r *http.Request) {
 			}
 		}
 
+		if roomA.Exits != nil {
+			if existing, ok := roomA.Exits[dir]; ok && existing.Room != body.To {
+				writeJSONError(w, fmt.Sprintf("%s in #%d already links to #%d", dir, body.From, existing.Room), http.StatusConflict)
+				return
+			}
+		}
+		if !body.OneWay {
+			if roomB.Exits != nil {
+				if existing, ok := roomB.Exits[oppDir]; ok && existing.Room != body.From {
+					writeJSONError(w, fmt.Sprintf("%s in #%d already links to #%d", oppDir, body.To, existing.Room), http.StatusConflict)
+					return
+				}
+			}
+		}
+
 		conflicts := 0
 		testGrid := world.BuildGrid(s.cfg.StartingRoom, func(id int) (*world.Room, bool) {
 			room, err := s.world.LoadRoom(id)
@@ -513,7 +529,7 @@ func (s *AdminServer) handleRoomLink(w http.ResponseWriter, r *http.Request) {
 			if id == body.From {
 				roomCopy.Exits[dir] = world.ExitDef{Room: body.To}
 			}
-			if id == body.To {
+			if id == body.To && !body.OneWay {
 				roomCopy.Exits[oppDir] = world.ExitDef{Room: body.From}
 			}
 			return &roomCopy, true
@@ -532,28 +548,23 @@ func (s *AdminServer) handleRoomLink(w http.ResponseWriter, r *http.Request) {
 		}
 		roomA.Exits[dir] = world.ExitDef{Room: body.To}
 
-		if roomB.Exits == nil {
-			roomB.Exits = make(map[world.ExitDir]world.ExitDef)
+		if !body.OneWay {
+			if roomB.Exits == nil {
+				roomB.Exits = make(map[world.ExitDir]world.ExitDef)
+			}
+			roomB.Exits[oppDir] = world.ExitDef{Room: body.From}
 		}
-		roomB.Exits[oppDir] = world.ExitDef{Room: body.From}
 
 		pathA, okA2 := s.world.GetRoomPath(body.From)
-		pathB, okB2 := s.world.GetRoomPath(body.To)
-		if !okA2 || !okB2 {
-			writeJSON(w, map[string]any{"error": "room path not found"})
+		if !okA2 {
+			writeJSONError(w, "room path not found", http.StatusInternalServerError)
 			return
 		}
 
 		oldA, _ := snapshotFile(pathA)
-		oldB, _ := snapshotFile(pathB)
 		newA, err := writeYAMLFile(pathA, roomA)
 		if err != nil {
-			writeJSON(w, map[string]any{"error": "write A: " + err.Error()})
-			return
-		}
-		newB, err := writeYAMLFile(pathB, roomB)
-		if err != nil {
-			writeJSON(w, map[string]any{"error": "write B: " + err.Error()})
+			writeJSONError(w, "write A: "+err.Error(), http.StatusInternalServerError)
 			return
 		}
 		s.undoStack.Push(ChangeDesc{
@@ -562,24 +573,39 @@ func (s *AdminServer) handleRoomLink(w http.ResponseWriter, r *http.Request) {
 			OldContent:  oldA,
 			NewContent:  newA,
 		})
-		s.undoStack.Push(ChangeDesc{
-			Description: fmt.Sprintf("link %d %s %d (reverse)", body.To, oppDir, body.From),
-			FilePath:    pathB,
-			OldContent:  oldB,
-			NewContent:  newB,
-		})
+
+		if !body.OneWay {
+			pathB, okB2 := s.world.GetRoomPath(body.To)
+			if !okB2 {
+				writeJSONError(w, "room B path not found", http.StatusInternalServerError)
+				return
+			}
+			oldB, _ := snapshotFile(pathB)
+			newB, err := writeYAMLFile(pathB, roomB)
+			if err != nil {
+				writeJSONError(w, "write B: "+err.Error(), http.StatusInternalServerError)
+				return
+			}
+			s.undoStack.Push(ChangeDesc{
+				Description: fmt.Sprintf("link %d %s %d (reverse)", body.To, oppDir, body.From),
+				FilePath:    pathB,
+				OldContent:  oldB,
+				NewContent:  newB,
+			})
+		}
 		writeJSON(w, map[string]any{"ok": true})
 
 	case http.MethodDelete:
 		var body struct {
-			From int `json:"from"`
-			To   int `json:"to"`
+			From int    `json:"from"`
+			To   int    `json:"to"`
+			Side string `json:"side"`
 		}
 		if err := readJSON(r, &body); err != nil || body.From <= 0 || body.To <= 0 {
 			if r.Body != nil {
 				r.Body.Close()
 			}
-			writeJSON(w, map[string]any{"error": "invalid body"})
+			writeJSONError(w, "invalid body", http.StatusBadRequest)
 			return
 		}
 
@@ -587,73 +613,83 @@ func (s *AdminServer) handleRoomLink(w http.ResponseWriter, r *http.Request) {
 		roomB, errB := s.world.LoadRoom(body.To)
 
 		if errA != nil && errB != nil {
-			writeJSON(w, map[string]any{"error": "both rooms not found"})
+			writeJSONError(w, "both rooms not found", http.StatusBadRequest)
 			return
 		}
 
-		var dir, oppDir world.ExitDir
+		var dirA, dirB world.ExitDir
 		if roomA != nil {
 			for _, d := range world.ExitOrder {
 				if exit, ok := roomA.Exits[d]; ok && exit.Room == body.To {
-					dir = d
-					oppDir = world.OppositeExit[d]
+					dirA = d
+					dirB = world.OppositeExit[d]
 					break
 				}
 			}
 		}
-		if dir == "" && roomB != nil {
+		if dirA == "" && roomB != nil {
 			for _, d := range world.ExitOrder {
 				if exit, ok := roomB.Exits[d]; ok && exit.Room == body.From {
-					oppDir = d
-					dir = world.OppositeExit[d]
+					dirB = d
+					dirA = world.OppositeExit[d]
 					break
 				}
 			}
 		}
 
-		if roomA != nil && roomA.Exits != nil {
-			delete(roomA.Exits, dir)
-		}
-		if roomB != nil && roomB.Exits != nil {
-			delete(roomB.Exits, oppDir)
+		if body.Side == "from" {
+			if roomA != nil && roomA.Exits != nil {
+				delete(roomA.Exits, dirA)
+			}
+		} else if body.Side == "to" {
+			if roomB != nil && roomB.Exits != nil {
+				delete(roomB.Exits, dirB)
+			}
+		} else {
+			if roomA != nil && roomA.Exits != nil {
+				delete(roomA.Exits, dirA)
+			}
+			if roomB != nil && roomB.Exits != nil {
+				delete(roomB.Exits, dirB)
+			}
 		}
 
 		var pushEntries []ChangeDesc
 
-		if roomA != nil {
+		if roomA != nil && (body.Side == "" || body.Side == "from") {
 			pathA, okA2 := s.world.GetRoomPath(body.From)
 			if !okA2 {
-				writeJSON(w, map[string]any{"error": "room A path not found"})
+				writeJSONError(w, "room A path not found", http.StatusInternalServerError)
 				return
 			}
 			oldA, _ := snapshotFile(pathA)
 			newA, err := writeYAMLFile(pathA, roomA)
 			if err != nil {
-				writeJSON(w, map[string]any{"error": "write A: " + err.Error()})
+				writeJSONError(w, "write A: "+err.Error(), http.StatusInternalServerError)
 				return
 			}
 			pushEntries = append(pushEntries, ChangeDesc{
-				Description: fmt.Sprintf("unlink %d %s %d", body.From, dir, body.To),
+				Description: fmt.Sprintf("unlink %d %s %d", body.From, dirA, body.To),
 				FilePath:    pathA,
 				OldContent:  oldA,
 				NewContent:  newA,
 			})
 		}
 
-		if roomB != nil {
+		if roomB != nil && (body.Side == "" || body.Side == "to") {
 			pathB, okB2 := s.world.GetRoomPath(body.To)
 			if !okB2 {
-				writeJSON(w, map[string]any{"error": "room B path not found"})
+				writeJSONError(w, "room B path not found", http.StatusInternalServerError)
 				return
 			}
 			oldB, _ := snapshotFile(pathB)
 			newB, err := writeYAMLFile(pathB, roomB)
 			if err != nil {
-				writeJSON(w, map[string]any{"error": "write B: " + err.Error()})
+				writeJSONError(w, "write B: "+err.Error(), http.StatusInternalServerError)
 				return
 			}
 			pushEntries = append(pushEntries, ChangeDesc{
-				Description: fmt.Sprintf("unlink %d %s %d (reverse)", body.To, oppDir, body.From),
+				Description: fmt.Sprintf("unlink %d %s %d (reverse)", body.To, dirB, body.From),
 				FilePath:    pathB,
 				OldContent:  oldB,
 				NewContent:  newB,
diff --git a/internal/admin/static/admin.css b/internal/admin/static/admin.css
index 376bf23..c620b46 100644
--- a/internal/admin/static/admin.css
+++ b/internal/admin/static/admin.css
@@ -51,6 +51,8 @@ body{font-family:monospace;background:var(--bg);color:var(--text);display:flex;f
 .z-controls .z-sep{width:1px;height:20px;background:var(--border);flex-shrink:0}
 .z-dir-form{display:none;position:absolute;left:0;top:calc(100% + 4px);background:var(--panel);border:1px solid var(--border);border-radius:4px;padding:8px 10px;z-index:11;gap:6px;align-items:center;white-space:nowrap}
 .room-tooltip{position:absolute;background:var(--panel);border:1px solid var(--border);padding:6px 10px;border-radius:3px;font-size:11px;pointer-events:none;z-index:20;white-space:nowrap}
+.link-mode-badge{position:absolute;bottom:12px;right:12px;padding:6px 12px;border-radius:4px;font-size:12px;font-family:monospace;pointer-events:none;z-index:20;background:rgba(30,30,60,0.9);color:#ccc;border:1px solid var(--border)}
+.link-mode-badge.oneway{background:rgba(80,50,20,0.92);color:#fca;border:1px solid #a64}
 .notification{position:fixed;bottom:16px;right:16px;background:var(--panel);border:1px solid var(--border);padding:10px 16px;border-radius:4px;font-size:12px;z-index:100;animation:fadeIn .2s}
 .notification.error{border-color:var(--danger)}
 .notification.success{border-color:var(--success)}
diff --git a/internal/admin/static/map.js b/internal/admin/static/map.js
index f0b4d87..f89a434 100644
--- a/internal/admin/static/map.js
+++ b/internal/admin/static/map.js
@@ -4,6 +4,8 @@ var panX = 0, panY = 0, scale = 1;
 var dragging = false, startX = 0, startY = 0, prevX = 0, prevY = 0;
 var dragRoom = false;
 var linkDrag = false, linkFromId = null, linkTargetId = null, linkGhostDir = null;
+var linkDragOneWay = false;
+var shiftHeld = false;
 var delDrag = false, delFromId = null, delTargetId = null;
 var roomMap = {}, occupied = {};
 var dirChangedByUser = false;
@@ -35,6 +37,7 @@ function onMapMouseMove(e) {
 
   if (linkFromId && moved) {
     linkDrag = true;
+    showDragBadge(linkDragOneWay ? 'One-way link' : 'Two-way link');
     updateLinkDragTarget(e);
   }
 }
@@ -62,7 +65,7 @@ function onMapMouseUp(e) {
   }
 
   if (linkDrag && linkFromId) {
-    if (linkTargetId) { createLink(linkFromId, linkTargetId); }
+    if (linkTargetId) { createLink(linkFromId, linkTargetId, linkDragOneWay); }
     else if (linkGhostDir) { createRoom(linkFromId, linkGhostDir); }
   } else if (!moved && !delDrag) {
     if (e.target.classList.contains('rm')) {
@@ -74,8 +77,9 @@ function onMapMouseUp(e) {
 
   clearLinkHighlight();
   clearDelHighlight();
+  hideDragBadge();
   dragging = false; dragRoom = false;
-  linkDrag = false; linkFromId = null; linkTargetId = null; linkGhostDir = null;
+  linkDrag = false; linkFromId = null; linkTargetId = null; linkGhostDir = null; linkDragOneWay = false;
   delDrag = false; delFromId = null; delTargetId = null;
 }
 
@@ -86,11 +90,25 @@ function cancelMapDrag() {
   _mapMouseCleanup = false;
   clearLinkHighlight();
   clearDelHighlight();
+  hideDragBadge();
   dragging = false; dragRoom = false;
-  linkDrag = false; linkFromId = null; linkTargetId = null; linkGhostDir = null;
+  linkDrag = false; linkFromId = null; linkTargetId = null; linkGhostDir = null; linkDragOneWay = false;
   delDrag = false; delFromId = null; delTargetId = null;
 }
 
+function showDragBadge(text) {
+  var badge = document.getElementById('linkModeBadge');
+  if (!badge) return;
+  badge.textContent = text;
+  badge.className = 'link-mode-badge' + (linkDragOneWay ? ' oneway' : '');
+  badge.style.display = '';
+}
+
+function hideDragBadge() {
+  var badge = document.getElementById('linkModeBadge');
+  if (badge) badge.style.display = 'none';
+}
+
 function changeZ(dz) {
   if (dz === 0) currentZ = 0; else currentZ += dz;
   panX = 0; panY = 0; scale = 1;
@@ -299,6 +317,7 @@ function renderMap(data) {
       return;
     }
 
+    e.preventDefault();
     dragRoom = onRoom || onGhost;
     dragging = true;
     startX = e.clientX; startY = e.clientY;
@@ -307,6 +326,7 @@ function renderMap(data) {
     linkDrag = false;
     linkTargetId = null;
     linkGhostDir = null;
+    linkDragOneWay = onRoom ? (e.shiftKey || shiftHeld) : false;
     delDrag = false; delFromId = null; delTargetId = null;
     clearLinkHighlight();
     document.addEventListener('mousemove', onMapMouseMove);
@@ -1160,13 +1180,16 @@ function renderExitsSection(r) {
     var setPlayerFlags = (typeof exit === 'object' && exit.set_player_flags) ? exit.set_player_flags : null;
     var hidden = (typeof exit === 'object' && exit.hidden) ? exit.hidden : false;
     var isConditional = !!(cond || bmsg || setFlags || setPlayerFlags || hidden);
+    var isBidi = mapData && mapData.links && mapData.links.some(function(l) {
+      return l.bidirectional && ((l.from === r.id && l.to === target) || (l.from === target && l.to === r.id));
+    });
     h += '<div class="exit-row" data-dir="' + d + '">';
     h += '<span class="exit-dir"' + (isConditional ? ' style="color:#f55"' : '') + '>' + d + '</span>';
     h += '<span class="exit-target" onclick="selectRoom(' + target + ')"># ' + target + '</span>';
-    h += '<label style="font-size:11px;margin-left:4px;cursor:pointer;color:#aaa"><input type="checkbox" class="exit-hidden" style="vertical-align:middle"' + (hidden ? ' checked' : '') + ' onchange="toggleExitHidden(\'' + d + '\')"> Hidden</label>';
     if (bmsg) h += '<span class="exit-meta">Blocked: ' + esc(bmsg) + '</span>';
     if (cond) h += '<span class="exit-meta">Conditional</span>';
     h += '<button class="btn btn-sm" onclick="editExitCondition(\'' + d + '\')">Edit</button>';
+    if (isBidi) h += '<button class="btn btn-sm" onclick="deleteLink(' + target + ',' + r.id + ',\'from\')" title="Remove reverse exit to make one-way">\u21C6</button>';
     h += '<button class="btn btn-sm btn-danger" onclick="deleteExit(\'' + d + '\', ' + target + ')">X</button>';
     h += '</div>';
   });
@@ -1175,6 +1198,7 @@ function renderExitsSection(r) {
   exitDirs.forEach(function(d) { h += '<option value="' + d + '">' + d + '</option>'; });
   h += '</select>';
   h += '<input id="exitTargetID" type="number" placeholder="Target ID">';
+  h += '<label style="font-size:11px;cursor:pointer;color:#aaa;margin:0 4px;display:flex;align-items:center;gap:3px"><input type="checkbox" id="exitReciprocal" checked style="vertical-align:middle"> Reciprocal</label>';
   h += '<button class="exit-add-btn" onclick="addExit()">Add</button>';
   h += '</div>';
   h += '</div>';
@@ -1421,8 +1445,13 @@ function addExit() {
   var dir = $('#exitDirSelect').value;
   var target = parseInt($('#exitTargetID').value);
   if (!dir || !target) { notify('Enter target room ID', 'error'); return; }
-  API.post('/api/rooms/link', {from: selectedRoom, to: target, dir: dir}).then(function() {
-    notify('Exit added: ' + dir + ' #' + target, 'success');
+  var reciprocalEl = $('#exitReciprocal');
+  var reciprocal = reciprocalEl ? reciprocalEl.checked : true;
+  var body = {from: selectedRoom, to: target, dir: dir};
+  if (!reciprocal) body.oneway = true;
+  API.post('/api/rooms/link', body).then(function(res) {
+    if (res && res.error) { notify('Add exit failed: ' + res.error, 'error'); return; }
+    notify('Exit added: ' + dir + ' #' + target + (reciprocal ? '' : ' (one-way)'), 'success');
     updateUndoBar();
     loadMap().then(function() { selectRoom(selectedRoom); });
   }).catch(function(e) { notify('Add exit failed: ' + extractError(e), 'error'); });
@@ -1430,15 +1459,17 @@ function addExit() {
 
 function deleteExit(dir, target) {
   if (!selectedRoom || !currentRoomData) return;
-  if (!confirm('Delete exit ' + dir + ' to #' + target + '?')) return;
   fetch('/api/rooms/link', {
     method: 'DELETE',
     headers: {'Content-Type': 'application/json'},
     body: JSON.stringify({from: selectedRoom, to: target}),
     credentials: 'same-origin'
   }).then(function(r) {
-    if (!r.ok) return r.json().then(function(j) { throw new Error(j.error || 'request failed'); });
-    return r.json();
+    return r.json().then(function(j) {
+      if (!r.ok) throw new Error(j.error || 'request failed');
+      if (j.error) throw new Error(j.error);
+      return j;
+    });
   }).then(function() {
     notify('Removed exit ' + dir + ' to #' + target, 'success');
     updateUndoBar();
@@ -2014,21 +2045,16 @@ function clearLinkHighlight() {
   }
 }
 
-function createLink(fromId, toId) {
-  API.post('/api/rooms/link', {from: fromId, to: toId}).then(function() {
-    notify('Linked rooms #'+fromId+' '+toId, 'success');
+function createLink(fromId, toId, oneway) {
+  var body = {from: fromId, to: toId};
+  if (oneway) body.oneway = true;
+  API.post('/api/rooms/link', body).then(function(res) {
+    if (res && res.error) { notify('Link failed: ' + res.error, 'error'); return; }
+    notify('Linked rooms #'+fromId+' '+toId + (oneway ? ' (one-way)' : ''), 'success');
     updateUndoBar();
-    if (mapData && mapData.rooms) {
-      var fr = mapData.rooms.find(function(r) { return r.id === fromId; });
-      var tr = mapData.rooms.find(function(r) { return r.id === toId; });
-      if (fr && tr) {
-        mapData.links = mapData.links || [];
-        mapData.links.push({from: fromId, to: toId, dir: gridDeltaToDir(tr.x - fr.x, tr.y - fr.y) || '', bidirectional: true});
-        renderMap(mapData);
-      }
-    }
+    loadMap().then(function() { selectRoom(selectedRoom); });
   }).catch(function(e) {
-    notify('Link failed: ' + e.message, 'error');
+    notify('Link failed: ' + extractError(e), 'error');
   });
 }
 
@@ -2105,26 +2131,26 @@ function clearDelHighlight() {
   }
 }
 
-function deleteLink(fromId, toId) {
+function deleteLink(fromId, toId, side) {
+  var body = {from: fromId, to: toId};
+  if (side) body.side = side;
   fetch('/api/rooms/link', {
     method: 'DELETE',
     headers: {'Content-Type': 'application/json'},
-    body: JSON.stringify({from: fromId, to: toId}),
+    body: JSON.stringify(body),
     credentials: 'same-origin'
   }).then(function(r) {
-    if (!r.ok) throw new Error('unlink failed');
-    return r.json();
+    return r.json().then(function(j) {
+      if (!r.ok) throw new Error(j.error || 'unlink failed');
+      if (j.error) throw new Error(j.error);
+      return j;
+    });
   }).then(function() {
-    notify('Removed link #'+fromId+' '+toId, 'success');
+    notify('Removed link #'+fromId+' '+toId + (side ? ' (' + side + ' side only)' : ''), 'success');
     updateUndoBar();
-    if (mapData && mapData.links) {
-      mapData.links = mapData.links.filter(function(l) {
-        return !((l.from === fromId && l.to === toId) || (l.from === toId && l.to === fromId));
-      });
-      renderMap(mapData);
-    }
+    loadMap().then(function() { selectRoom(selectedRoom); });
   }).catch(function(e) {
-    notify('Delete link failed: ' + e.message, 'error');
+    notify('Delete link failed: ' + extractError(e), 'error');
   });
 }
 
@@ -2368,4 +2394,7 @@ function reloadRoomDirs(cb) {
   });
 }
 
-document.addEventListener('DOMContentLoaded', function() { loadRoomDirs(function() { loadMap(); }); initPanelResize(); });
+document.addEventListener('DOMContentLoaded', function() { loadRoomDirs(function() { loadMap(); }); initPanelResize();
+  document.addEventListener('keydown', function(e) { if (e.key === 'Shift') shiftHeld = true; });
+  document.addEventListener('keyup', function(e) { if (e.key === 'Shift') shiftHeld = false; });
+});
diff --git a/internal/admin/templates/map.html b/internal/admin/templates/map.html
index 1e45f8e..eb95db7 100644
--- a/internal/admin/templates/map.html
+++ b/internal/admin/templates/map.html
@@ -42,6 +42,7 @@
     </div>
     <svg id="mapSvg" style="width:100%;height:100%"></svg>
     <div class="room-tooltip" id="tooltip" style="display:none"></div>
+    <div id="linkModeBadge" class="link-mode-badge" style="display:none"></div>
   </div>
   <div class="panel" id="sidePanel">
     <div id="panelContent">