diff --git a/CLI/cmux.swift b/CLI/cmux.swift
index a68ac6fd..d0c69360 100644
--- a/CLI/cmux.swift
+++ b/CLI/cmux.swift
@@ -9779,30 +9779,14 @@ struct CMUXCLI {
             } else {
                 throw CLIError(message: "Neither bun nor npm found in PATH. Install oh-my-opencode manually: bunx oh-my-opencode install")
             }
-            let stdoutPipe = Pipe()
-            let stderrPipe = Pipe()
-            process.standardOutput = stdoutPipe
-            process.standardError = stderrPipe
-            FileHandle.standardError.write("Installing oh-my-opencode plugin...\n".data(using: .utf8)!)
+            // Show install output directly so the user sees progress (npm can take 30s+)
+            process.standardOutput = FileHandle.standardError
+            process.standardError = FileHandle.standardError
+            FileHandle.standardError.write("Installing oh-my-opencode plugin (this may take a minute on first run)...\n".data(using: .utf8)!)
             try process.run()
-            // Drain pipes concurrently to prevent deadlock from full buffers
-            var stderrData = Data()
-            let drainGroup = DispatchGroup()
-            drainGroup.enter()
-            DispatchQueue.global().async {
-                stderrData = stderrPipe.fileHandleForReading.readDataToEndOfFile()
-                drainGroup.leave()
-            }
-            drainGroup.enter()
-            DispatchQueue.global().async {
-                _ = stdoutPipe.fileHandleForReading.readDataToEndOfFile()
-                drainGroup.leave()
-            }
-            drainGroup.wait()
             process.waitUntilExit()
             if process.terminationStatus != 0 {
-                let errText = String(data: stderrData, encoding: .utf8) ?? ""
-                throw CLIError(message: "Failed to install oh-my-opencode: \(errText)")
+                throw CLIError(message: "Failed to install oh-my-opencode. Try manually: npm install -g oh-my-opencode")
             }
             FileHandle.standardError.write("oh-my-opencode plugin installed\n".data(using: .utf8)!)
             // Re-create symlink if we installed into user dir
@@ -9899,9 +9883,6 @@ struct CMUXCLI {
         socketPath: String,
         explicitPassword: String?
     ) throws {
-        // Ensure oh-my-opencode plugin is registered and installed
-        try omoEnsurePlugin()
-
         let processEnvironment = ProcessInfo.processInfo.environment
         var launcherEnvironment = processEnvironment
         launcherEnvironment["CMUX_SOCKET_PATH"] = socketPath
@@ -9910,13 +9891,31 @@ struct CMUXCLI {
            !explicitPassword.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty {
             launcherEnvironment["CMUX_SOCKET_PASSWORD"] = explicitPassword
         }
+
+        // Check for opencode before doing expensive plugin setup
+        let openCodeExecutablePath = resolveOpenCodeExecutable(searchPath: launcherEnvironment["PATH"])
+        if openCodeExecutablePath == nil {
+            let checkProcess = Process()
+            checkProcess.executableURL = URL(fileURLWithPath: "/usr/bin/which")
+            checkProcess.arguments = ["opencode"]
+            checkProcess.standardOutput = Pipe()
+            checkProcess.standardError = Pipe()
+            try? checkProcess.run()
+            checkProcess.waitUntilExit()
+            if checkProcess.terminationStatus != 0 {
+                throw CLIError(message: "opencode is not installed. Install it first:\n  npm install -g opencode-ai\n  # or\n  bun install -g opencode-ai\n\nThen run: cmux omo")
+            }
+        }
+
+        // Ensure oh-my-opencode plugin is registered and installed
+        try omoEnsurePlugin()
+
         let shimDirectory = try createOMOShimDirectory()
         let executablePath = resolvedExecutableURL()?.path ?? (args.first ?? "cmux")
         let focusedContext = tmuxCompatFocusedContext(
             processEnvironment: launcherEnvironment,
             explicitPassword: explicitPassword
         )
-        let openCodeExecutablePath = resolveOpenCodeExecutable(searchPath: launcherEnvironment["PATH"])
         configureOMOEnvironment(
             processEnvironment: launcherEnvironment,
             shimDirectory: shimDirectory,
@@ -9949,7 +9948,7 @@ struct CMUXCLI {
             execvp("opencode", &argv)
         }
         let code = errno
-        throw CLIError(message: "Failed to launch opencode: \(String(cString: strerror(code)))")
+        throw CLIError(message: "Failed to launch opencode: \(String(cString: strerror(code)))\n\nIs opencode installed? Install with:\n  npm install -g opencode-ai")
     }
 
     private func runClaudeTeamsTmuxCompat(