diff --git a/desktop/src/features/agents/ui/AgentEditDialog.tsx b/desktop/src/features/agents/ui/AgentEditDialog.tsx
index bf8a09888d..74c86392dc 100644
--- a/desktop/src/features/agents/ui/AgentEditDialog.tsx
+++ b/desktop/src/features/agents/ui/AgentEditDialog.tsx
@@ -47,8 +47,10 @@ import type {
 } from "@/shared/api/types";
 import type { EditAgentFocusTarget } from "@/features/agents/openEditAgentEvent";
 import type { AgentDefinitionSubmitOptions } from "./AgentDefinitionDialog";
+import { runLocationForBackend } from "@/features/agents/lib/agentAccessWarning";
 import { AgentDefinitionDialog } from "./AgentDefinitionDialog";
 import { AgentInstanceEditDialog } from "./AgentInstanceEditDialog";
+import { AgentRunLocationProvider } from "./AgentRunLocationContext";
 import { editPersonaDialogState } from "./personaDialogState";
 
 // ── Types ─────────────────────────────────────────────────────────────────────
@@ -103,18 +105,26 @@ export function AgentEditDialog({
   // parallelism, env vars, harness pin, auto-restart, start-on-launch, instance
   // name) and owns a well-tested save path. Route all instance-present contexts
   // here so no I/L field is accidentally omitted.
+  //
+  // Wrap in AgentRunLocationProvider so RespondToField's access warning can
+  // name the machine the agent actually runs on (mirrors AgentDialog's instance-
+  // edit arm — backend → run location for the remote-backend warning path).
   if (ctx.kind === "instance-with-definition" || ctx.kind === "instance-only") {
     return (
-      <AgentInstanceEditDialog
-        agent={ctx.instance}
-        initialFocus={initialFocus}
-        open={open}
-        onOpenChange={onOpenChange}
-        onUpdated={onUpdated}
-        // R4 back-door deleted: avatar lives on the merged surface (definition
-        // section is visible in the profile panel when a definition exists).
-        onEditLinkedPersona={undefined}
-      />
+      <AgentRunLocationProvider
+        runLocation={runLocationForBackend(ctx.instance.backend)}
+      >
+        <AgentInstanceEditDialog
+          agent={ctx.instance}
+          initialFocus={initialFocus}
+          open={open}
+          onOpenChange={onOpenChange}
+          onUpdated={onUpdated}
+          // R4 back-door deleted: avatar lives on the merged surface (definition
+          // section is visible in the profile panel when a definition exists).
+          onEditLinkedPersona={undefined}
+        />
+      </AgentRunLocationProvider>
     );
   }
 
diff --git a/desktop/src/features/agents/ui/agentDialogRouting.test.mjs b/desktop/src/features/agents/ui/agentDialogRouting.test.mjs
index 15b6b7cf87..ecf1d68bc7 100644
--- a/desktop/src/features/agents/ui/agentDialogRouting.test.mjs
+++ b/desktop/src/features/agents/ui/agentDialogRouting.test.mjs
@@ -5,6 +5,7 @@ import { AgentDialog } from "./AgentDialog.tsx";
 import { AgentDefinitionDialog } from "./AgentDefinitionDialog.tsx";
 import { AgentInstanceEditDialog } from "./AgentInstanceEditDialog.tsx";
 import { AgentRunLocationProvider } from "./AgentRunLocationContext.tsx";
+import { AgentEditDialog } from "./AgentEditDialog.tsx";
 
 // ── Phase 1B.3c routing pinning ─────────────────────────────────────────────
 //
@@ -110,3 +111,124 @@ test("create mode routes to the internal create router, not a form directly", ()
   );
   assert.equal(element.type.name, "AgentCreateDialogRouter");
 });
+
+// ── Phase 1 merged surface routing (AgentEditDialog) ────────────────────────
+//
+// AgentEditDialog collapses R1–R7 onto one entry point.  Like AgentDialog, the
+// instance-present arms are hook-free so they can be called directly and the
+// returned element tree inspected.  The definition-only arm delegates to a
+// sub-component that owns hooks, so we only confirm the type name there.
+//
+// These tests prove:
+//   • instance-with-definition → AgentInstanceEditDialog (all I/L fields live here)
+//   • instance-only            → AgentInstanceEditDialog (unlinked agents save correctly)
+//   • definition-only          → AgentEditDefinitionOnlyDialog sub-component
+//
+// They also confirm the AgentRunLocationProvider wrapper is present on instance
+// paths (so RespondToField's remote-backend warning works).
+
+const minimalDefinition = {
+  id: "def-abc",
+  displayName: "Bot",
+  avatarUrl: "",
+  systemPrompt: "Do stuff.",
+  runtime: "goose",
+  model: null,
+  provider: null,
+  isBuiltIn: false,
+  isActive: true,
+  namePool: [],
+  envVars: {},
+  respondTo: null,
+  respondToAllowlist: [],
+  parallelism: null,
+  createdAt: "2025-01-01T00:00:00Z",
+  updatedAt: "2025-01-01T00:00:00Z",
+};
+
+const minimalInstance = {
+  pubkey: "pk-0000",
+  name: "Bot",
+  avatarUrl: "",
+  systemPrompt: "Do stuff.",
+  model: null,
+  provider: null,
+  envVars: {},
+  respondTo: null,
+  respondToAllowlist: [],
+  parallelism: null,
+  autoRestartOnConfigChange: false,
+  startOnAppLaunch: false,
+};
+
+test("AgentEditDialog: instance-with-definition routes instance to AgentInstanceEditDialog", () => {
+  const ctx = {
+    kind: "instance-with-definition",
+    definition: minimalDefinition,
+    instance: minimalInstance,
+  };
+
+  const element = AgentEditDialog({
+    ctx,
+    open: true,
+    onOpenChange: noop,
+  });
+
+  // Wrapped in AgentRunLocationProvider for respondTo warning.
+  assert.equal(element.type, AgentRunLocationProvider);
+  const form = element.props.children;
+  assert.equal(
+    form.type,
+    AgentInstanceEditDialog,
+    "linked agent edit must reach AgentInstanceEditDialog (all I/L fields)",
+  );
+  assert.equal(form.props.agent, minimalInstance);
+  assert.equal(form.props.open, true);
+  assert.equal(
+    form.props.onEditLinkedPersona,
+    undefined,
+    "R4 back-door must be deleted",
+  );
+});
+
+test("AgentEditDialog: instance-only routes to AgentInstanceEditDialog (unlinked save)", () => {
+  const ctx = { kind: "instance-only", instance: minimalInstance };
+
+  const element = AgentEditDialog({
+    ctx,
+    open: true,
+    onOpenChange: noop,
+  });
+
+  // Wrapped in AgentRunLocationProvider for respondTo warning.
+  assert.equal(element.type, AgentRunLocationProvider);
+  const form = element.props.children;
+  assert.equal(
+    form.type,
+    AgentInstanceEditDialog,
+    "unlinked agent edit must reach AgentInstanceEditDialog (UpdateManagedAgentInput path)",
+  );
+  assert.equal(form.props.agent, minimalInstance);
+});
+
+test("AgentEditDialog: definition-only routes to definition sub-component", () => {
+  const ctx = { kind: "definition-only", definition: minimalDefinition };
+
+  const element = AgentEditDialog({
+    ctx,
+    open: true,
+    onOpenChange: noop,
+  });
+
+  // Hook-bearing sub-component: confirm by name rather than reference.
+  assert.equal(
+    typeof element.type,
+    "function",
+    "definition-only must route to a React component",
+  );
+  assert.equal(
+    element.type.name,
+    "AgentEditDefinitionOnlyDialog",
+    "definition-only must use the coordinator-wired sub-component",
+  );
+});