fix: clarify Tahoe typing failures

CHANGELOG.md

@@ -23,6 +23,7 @@
 - fix: dedupe URL balloon preview duplicates in watch stream without cross-chat/schema regressions (#64, thanks @lesaai)
 - fix: normalize IMCore typing chat lookup across `iMessage`, `SMS`, and `any` prefixes (#51, #54, #56, #58)
 - docs: document macOS 26 advanced IMCore injection limits (#60)
+- fix: report macOS 26/Tahoe IMCore typing entitlement failures as advanced-feature setup errors (#60)
 - docs: add a local release helper for dispatching Homebrew tap updates (#97, thanks @dinakars777)
 - feat: resolve contact names in chat/message output and direct sends (#75, #77, thanks @regaw-leinad and @jsindy)
 

README.md

@@ -144,6 +144,9 @@ Important:
 - macOS 26 can also block Messages.app dylib injection with library validation.
   In that case `imsg status` reports advanced features unavailable even with SIP
   disabled; normal send/history/watch commands still work.
+- On macOS 26/Tahoe, direct IMCore access can also fail because `imagent`
+  rejects clients without Apple-private entitlements. That only affects advanced
+  IMCore features such as `typing`.
 
 Setup:
 1) Disable SIP from Recovery mode: `csrutil disable`

Sources/IMsgCore/IMCoreBridge.swift

@@ -23,8 +23,9 @@ public enum IMCoreBridgeError: Error, CustomStringConvertible {
 /// Bridge to IMCore via DYLD injection into Messages.app.
 ///
 /// Communicates with an injected dylib inside Messages.app via file-based IPC.
-/// The dylib has full access to IMCore because it runs within the Messages.app
-/// context with proper entitlements.
+/// The dylib has access to IMCore when Messages.app accepts the injection.
+/// macOS 26/Tahoe can still block this path with library validation/private
+/// entitlement checks.
 ///
 /// Requires:
 /// - SIP disabled (for `DYLD_INSERT_LIBRARIES` on system apps)
@@ -139,6 +140,10 @@ public final class IMCoreBridge: @unchecked Sendable {
       """
       SIP is disabled and the helper dylib is present, but Messages.app is not currently injected.
       Run `imsg launch` to enable advanced IMCore features.
+
+      Note: macOS 26/Tahoe can still block advanced IMCore features through
+      library validation or imagent private entitlement checks. Basic send,
+      history, and watch commands do not use this path.
       """
     )
   }

Sources/IMsgCore/TypingIndicator.swift

@@ -134,6 +134,7 @@ public struct TypingIndicator: Sendable {
     if hasLiveDaemonConnection(controller) {
       daemonConnectionTracker.lock.lock()
       daemonConnectionTracker.hasAttemptedConnection = true
+      daemonConnectionTracker.connectionKnownUnavailable = false
       daemonConnectionTracker.lock.unlock()
       return
     }
@@ -154,6 +155,9 @@ public struct TypingIndicator: Sendable {
     let maxAttempts = 50
     for _ in 0..<maxAttempts {
       if hasLiveDaemonConnection(controller) {
+        daemonConnectionTracker.lock.lock()
+        daemonConnectionTracker.connectionKnownUnavailable = false
+        daemonConnectionTracker.lock.unlock()
         return
       }
       Thread.sleep(forTimeInterval: 0.1)
@@ -161,11 +165,11 @@ public struct TypingIndicator: Sendable {
     }
 
     if !hasLiveDaemonConnection(controller) {
+      daemonConnectionTracker.lock.lock()
+      daemonConnectionTracker.connectionKnownUnavailable = true
+      daemonConnectionTracker.lock.unlock()
       throw IMsgError.typingIndicatorFailed(
-        "Failed to connect to imagent (iMessage daemon). "
-          + "This requires either SIP disabled with 'imsg launch', "
-          + "or system modifications (AMFI disabled + XPC plist). "
-          + "Run 'imsg status' for setup instructions."
+        daemonUnavailableMessage()
       )
     }
   }
@@ -221,11 +225,27 @@ public struct TypingIndicator: Sendable {
       }
     }
 
+    daemonConnectionTracker.lock.lock()
+    let connectionKnownUnavailable = daemonConnectionTracker.connectionKnownUnavailable
+    daemonConnectionTracker.lock.unlock()
+    if connectionKnownUnavailable {
+      throw IMsgError.typingIndicatorFailed(daemonUnavailableMessage())
+    }
+
     throw IMsgError.typingIndicatorFailed(
       "Chat not found for identifier: \(identifier). "
         + "Make sure Messages.app has an active conversation with this contact.")
   }
 
+  static func daemonUnavailableMessage() -> String {
+    "Failed to connect to imagent (Messages daemon) for IMCore typing indicators. "
+      + "On macOS 26/Tahoe, imagent can reject third-party clients without "
+      + "Apple-private entitlements, and Messages.app may also block the injected "
+      + "bridge via library validation. Run 'imsg status' and 'imsg launch' to "
+      + "verify advanced feature setup. Normal 'send', 'history', and 'watch' "
+      + "commands do not use this IMCore path."
+  }
+
   static func chatLookupCandidates(for identifier: String) -> [String] {
     let trimmed = identifier.trimmingCharacters(in: .whitespacesAndNewlines)
     guard !trimmed.isEmpty else { return [] }
@@ -272,6 +292,7 @@ public struct TypingIndicator: Sendable {
 private final class DaemonConnectionTracker: @unchecked Sendable {
   let lock = NSLock()
   var hasAttemptedConnection = false
+  var connectionKnownUnavailable = false
 }
 
 /// Thread-safe box for passing an error out of a Task back to the calling thread.

Sources/imsg/Commands/StatusCommand.swift

@@ -81,6 +81,14 @@ enum StatusCommand {
         StdoutWriter.writeLine("     make build-dylib")
         StdoutWriter.writeLine("     imsg launch")
         StdoutWriter.writeLine("")
+        StdoutWriter.writeLine("macOS 26/Tahoe note:")
+        StdoutWriter.writeLine(
+          "  Advanced IMCore features may still be blocked by library validation"
+        )
+        StdoutWriter.writeLine(
+          "  or imagent private entitlement checks. Basic commands still work."
+        )
+        StdoutWriter.writeLine("")
         StdoutWriter.writeLine("Note: Basic messaging features work without these steps.")
       }
     }

Tests/IMsgCoreTests/TypingIndicatorTests.swift

@@ -78,3 +78,16 @@ func typingLookupCandidatesAvoidDoublePrefixingDirectIdentifiers() {
 func typingLookupCandidatesRejectBlankIdentifier() {
   #expect(TypingIndicator.chatLookupCandidates(for: "   ").isEmpty)
 }
+
+@Test
+func typingDaemonUnavailableMessageExplainsTahoeEntitlementBlock() {
+  let message = TypingIndicator.daemonUnavailableMessage()
+
+  #expect(message.contains("imagent"))
+  #expect(message.contains("macOS 26/Tahoe"))
+  #expect(message.contains("Apple-private entitlements"))
+  #expect(message.contains("imsg status"))
+  #expect(message.contains("send"))
+  #expect(message.contains("history"))
+  #expect(message.contains("watch"))
+}