diff --git a/hosts/Volcanic.AgenticCore.Telegram/Chats/ChatRegistry.cs b/hosts/Volcanic.AgenticCore.Telegram/Chats/ChatRegistry.cs
index 97e6e16..7d6dade 100644
--- a/hosts/Volcanic.AgenticCore.Telegram/Chats/ChatRegistry.cs
+++ b/hosts/Volcanic.AgenticCore.Telegram/Chats/ChatRegistry.cs
@@ -82,7 +82,11 @@ public sealed class ChatRegistry(
 
     public static string ScopeFor(long chatId) => $"telegram-{chatId}";
 
-    public string WorkspaceFor(long chatId) => Path.Combine(options.WorkspaceRoot, chatId.ToString(System.Globalization.CultureInfo.InvariantCulture));
+    public string WorkspaceFor(long chatId) => WorkspaceFor(options, chatId);
+
+    /// <summary><c>&lt;WorkspaceRoot&gt;/&lt;chatId&gt;</c>, for services that can't depend on the registry (it would close a DI cycle).</summary>
+    public static string WorkspaceFor(TelegramOptions options, long chatId) =>
+        Path.Combine(options.WorkspaceRoot, chatId.ToString(System.Globalization.CultureInfo.InvariantCulture));
 
     /// <summary>The chat's context if it was already created, without creating it.</summary>
     public ChatContext? Find(long chatId) =>
diff --git a/hosts/Volcanic.AgenticCore.Telegram/Scheduling/CalendarScriptEnvironment.cs b/hosts/Volcanic.AgenticCore.Telegram/Scheduling/CalendarScriptEnvironment.cs
index 2f24f76..e0dd56a 100644
--- a/hosts/Volcanic.AgenticCore.Telegram/Scheduling/CalendarScriptEnvironment.cs
+++ b/hosts/Volcanic.AgenticCore.Telegram/Scheduling/CalendarScriptEnvironment.cs
@@ -9,8 +9,10 @@ namespace Volcanic.AgenticCore.Telegram.Scheduling;
 /// Gives a chat's watcher scripts <c>GOOGLE_ACCESS_TOKEN</c>: an access token for that chat's calendar, valid for the
 /// run's timeout plus a minute (as far as Google's one-hour lifetime allows). The bot refreshes it; the refresh token
 /// and the client secret never reach the script. A chat without a connected calendar gets nothing.
+/// Takes <see cref="TelegramOptions"/>, not <see cref="ChatRegistry"/>: the registry depends on the scheduler, which
+/// depends on this.
 /// </summary>
-public sealed class CalendarScriptEnvironment(ChatRegistry chats, GoogleCalendarOptions calendar) : IScriptEnvironment
+public sealed class CalendarScriptEnvironment(TelegramOptions options, GoogleCalendarOptions calendar) : IScriptEnvironment
 {
     public const string AccessTokenVariable = "GOOGLE_ACCESS_TOKEN";
     private static readonly TimeSpan Margin = TimeSpan.FromMinutes(1);
@@ -20,7 +22,7 @@ public sealed class CalendarScriptEnvironment(ChatRegistry chats, GoogleCalendar
     {
         if (!long.TryParse(target, NumberStyles.AllowLeadingSign, CultureInfo.InvariantCulture, out var chatId)) return None;
         var token = await (calendar.Connections ?? GoogleCalendarConnections.Shared)
-            .TryGetAccessTokenAsync(calendar, ChatRegistry.ScopeFor(chatId), chats.WorkspaceFor(chatId), timeout + Margin, cancellationToken)
+            .TryGetAccessTokenAsync(calendar, ChatRegistry.ScopeFor(chatId), ChatRegistry.WorkspaceFor(options, chatId), timeout + Margin, cancellationToken)
             .ConfigureAwait(false);
         return token is null ? None : new Dictionary<string, string> { [AccessTokenVariable] = token };
     }
diff --git a/tests/Volcanic.AgenticCore.Telegram.Tests/GoogleCalendarHostTests.cs b/tests/Volcanic.AgenticCore.Telegram.Tests/GoogleCalendarHostTests.cs
index 8908d6d..59fe5e8 100644
--- a/tests/Volcanic.AgenticCore.Telegram.Tests/GoogleCalendarHostTests.cs
+++ b/tests/Volcanic.AgenticCore.Telegram.Tests/GoogleCalendarHostTests.cs
@@ -166,7 +166,7 @@ public class GoogleCalendarHostTests : IDisposable
     {
         var calendar = Calendar();
         await using var host = new ChatHost(calendar: calendar);
-        var environment = new Volcanic.AgenticCore.Telegram.Scheduling.CalendarScriptEnvironment(host.Chats, calendar);
+        var environment = new Volcanic.AgenticCore.Telegram.Scheduling.CalendarScriptEnvironment(host.Options, calendar);
         var target = Updates.AllowedUser.ToString(System.Globalization.CultureInfo.InvariantCulture);
         Assert.Empty(await environment.ForRunAsync(target, TimeSpan.FromMinutes(5), CancellationToken.None)); // not connected yet