diff --git a/Packages/macOS/CMUXAgentLaunch/Sources/CMUXAgentLaunch/Workstream/WorkstreamEvent.swift b/Packages/macOS/CMUXAgentLaunch/Sources/CMUXAgentLaunch/Workstream/WorkstreamEvent.swift
index b3c1ee31cd79..53ce252eb359 100644
--- a/Packages/macOS/CMUXAgentLaunch/Sources/CMUXAgentLaunch/Workstream/WorkstreamEvent.swift
+++ b/Packages/macOS/CMUXAgentLaunch/Sources/CMUXAgentLaunch/Workstream/WorkstreamEvent.swift
@@ -5,13 +5,14 @@ import Foundation
 ///
 /// Field names mirror Vibe Island's hook payload format exactly so existing
 /// agent payloads pass through untouched: `session_id`, `hook_event_name`,
-/// `workspace_id`, `cwd`, `tool_name`, `tool_input`, `_source`, `_ppid`,
-/// `_opencode_request_id`. `context` is cmux-specific and optional.
+/// `workspace_id`, `surface_id`, `cwd`, `tool_name`, `tool_input`, `_source`,
+/// `_ppid`, `_opencode_request_id`. `context` is cmux-specific and optional.
 public struct WorkstreamEvent: Codable, Sendable, Equatable {
     public let sessionId: String
     public let hookEventName: HookEventName
     public let source: String
     public let workspaceId: String?
+    public let surfaceId: String?
     public let cwd: String?
     public let toolName: String?
     public let toolInputJSON: String?
@@ -26,6 +27,7 @@ public struct WorkstreamEvent: Codable, Sendable, Equatable {
         hookEventName: HookEventName,
         source: String,
         workspaceId: String? = nil,
+        surfaceId: String? = nil,
         cwd: String? = nil,
         toolName: String? = nil,
         toolInputJSON: String? = nil,
@@ -39,6 +41,7 @@ public struct WorkstreamEvent: Codable, Sendable, Equatable {
         self.hookEventName = hookEventName
         self.source = source
         self.workspaceId = workspaceId
+        self.surfaceId = surfaceId
         self.cwd = cwd
         self.toolName = toolName
         self.toolInputJSON = toolInputJSON
@@ -72,6 +75,7 @@ public struct WorkstreamEvent: Codable, Sendable, Equatable {
         case hookEventName = "hook_event_name"
         case source = "_source"
         case workspaceId = "workspace_id"
+        case surfaceId = "surface_id"
         case cwd
         case toolName = "tool_name"
         case toolInputJSON = "tool_input"
@@ -87,6 +91,7 @@ public struct WorkstreamEvent: Codable, Sendable, Equatable {
         self.hookEventName = try c.decode(HookEventName.self, forKey: .hookEventName)
         self.source = try c.decode(String.self, forKey: .source)
         self.workspaceId = try c.decodeIfPresent(String.self, forKey: .workspaceId)
+        self.surfaceId = try c.decodeIfPresent(String.self, forKey: .surfaceId)
         self.cwd = try c.decodeIfPresent(String.self, forKey: .cwd)
         self.toolName = try c.decodeIfPresent(String.self, forKey: .toolName)
         self.context = try c.decodeIfPresent(WorkstreamContext.self, forKey: .context)
@@ -117,6 +122,7 @@ public struct WorkstreamEvent: Codable, Sendable, Equatable {
         try c.encode(hookEventName, forKey: .hookEventName)
         try c.encode(source, forKey: .source)
         try c.encodeIfPresent(workspaceId, forKey: .workspaceId)
+        try c.encodeIfPresent(surfaceId, forKey: .surfaceId)
         try c.encodeIfPresent(cwd, forKey: .cwd)
         try c.encodeIfPresent(toolName, forKey: .toolName)
         try c.encodeIfPresent(context, forKey: .context)
diff --git a/Resources/opencode-plugin.js b/Resources/opencode-plugin.js
index 6e8a9a63402f..039c214c5028 100644
--- a/Resources/opencode-plugin.js
+++ b/Resources/opencode-plugin.js
@@ -408,6 +408,10 @@ export const CMUXFeed = async (ctx) => {
       typeof process.env.CMUX_WORKSPACE_ID === "string" && process.env.CMUX_WORKSPACE_ID.trim()
         ? process.env.CMUX_WORKSPACE_ID.trim()
         : null;
+    const surfaceId =
+      typeof process.env.CMUX_SURFACE_ID === "string" && process.env.CMUX_SURFACE_ID.trim()
+        ? process.env.CMUX_SURFACE_ID.trim()
+        : null;
     const event = {
       session_id: `opencode-${sessionId}`,
       _source: "opencode",
@@ -416,6 +420,7 @@ export const CMUXFeed = async (ctx) => {
       ...extra,
     };
     if (workspaceId) event.workspace_id = workspaceId;
+    if (surfaceId) event.surface_id = surfaceId;
     if (context) event.context = context;
     return event;
   };
diff --git a/Sources/Feed/FeedCoordinator.swift b/Sources/Feed/FeedCoordinator.swift
index 2d0ae80a7521..3e7cc50a09e9 100644
--- a/Sources/Feed/FeedCoordinator.swift
+++ b/Sources/Feed/FeedCoordinator.swift
@@ -464,9 +464,11 @@ extension FeedCoordinator {
     /// The workspace prefers the event's live `workspace_id` (the running
     /// terminal's CMUX_WORKSPACE_ID, a raw UUID) so a stale hook-session map
     /// can't redirect attention to the wrong workspace; it falls back to the
-    /// session store when the event omits a parseable id. The surface comes
-    /// from the session store only when its workspace matches the resolved
-    /// workspace, so a stale entry can't point the panel elsewhere.
+    /// session store when the event omits a parseable id. The surface prefers
+    /// the event's live `surface_id` (CMUX_SURFACE_ID) so the overlay lands on
+    /// the pane the agent actually ran in; it falls back to the session store
+    /// only when that store's workspace matches the resolved workspace, so a
+    /// stale entry can't point the panel elsewhere.
     private static func resolveAttentionTarget(
         event: WorkstreamEvent
     ) -> (workspaceId: UUID, surfaceId: UUID?)? {
@@ -481,13 +483,15 @@ extension FeedCoordinator {
         let eventWorkspaceId = event.workspaceId.flatMap {
             UUID(uuidString: $0.trimmingCharacters(in: .whitespacesAndNewlines))
         }
+        let eventSurfaceId = event.surfaceId.flatMap {
+            UUID(uuidString: $0.trimmingCharacters(in: .whitespacesAndNewlines))
+        }
 
         guard let workspaceId = eventWorkspaceId ?? sessionMatch?.workspaceId else {
             return nil
         }
-        // Only trust the session store's surface if it belongs to the
-        // workspace we're actually targeting.
-        let surfaceId = (sessionMatch?.workspaceId == workspaceId) ? sessionMatch?.surfaceId : nil
+        let surfaceId = eventSurfaceId
+            ?? ((sessionMatch?.workspaceId == workspaceId) ? sessionMatch?.surfaceId : nil)
         return (workspaceId, surfaceId)
     }