diff --git a/apps/macos/Sources/Clawdis/AgentRPC.swift b/apps/macos/Sources/Clawdis/AgentRPC.swift
new file mode 100644
index 000000000..b790f26b8
--- /dev/null
+++ b/apps/macos/Sources/Clawdis/AgentRPC.swift
@@ -0,0 +1,127 @@
+import Foundation
+import OSLog
+
+actor AgentRPC {
+    static let shared = AgentRPC()
+
+    private var process: Process?
+    private var stdinHandle: FileHandle?
+    private var stdoutHandle: FileHandle?
+    private var buffer = Data()
+    private var waiters: [CheckedContinuation<String, Error>] = []
+    private let logger = Logger(subsystem: "com.steipete.clawdis", category: "agent.rpc")
+
+    private struct RpcError: Error { let message: String }
+
+    func send(text: String, thinking: String?, session: String) async -> (ok: Bool, text: String?, error: String?) {
+        do {
+            try await ensureRunning()
+            let payload: [String: Any] = [
+                "type": "send",
+                "text": text,
+                "session": session,
+                "thinking": thinking ?? "default",
+            ]
+            let data = try JSONSerialization.data(withJSONObject: payload)
+            guard let stdinHandle else { throw RpcError(message: "stdin missing") }
+            stdinHandle.write(data)
+            stdinHandle.write(Data([0x0A]))
+
+            let line = try await nextLine()
+            let parsed = try JSONSerialization.jsonObject(with: Data(line.utf8)) as? [String: Any]
+            guard let parsed else { throw RpcError(message: "invalid JSON") }
+
+            if let ok = parsed["ok"] as? Bool, let type = parsed["type"] as? String, type == "result" {
+                if ok {
+                    if let payloadDict = parsed["payload"] as? [String: Any],
+                       let payloads = payloadDict["payloads"] as? [[String: Any]],
+                       let first = payloads.first,
+                       let txt = first["text"] as? String {
+                        return (true, txt, nil)
+                    }
+                    return (true, nil, nil)
+                }
+            }
+            if let err = parsed["error"] as? String {
+                return (false, nil, err)
+            }
+            return (false, nil, "rpc returned unexpected response")
+        } catch {
+            logger.error("rpc send failed: \(error.localizedDescription, privacy: .public)")
+            await stop()
+            return (false, nil, error.localizedDescription)
+        }
+    }
+
+    // MARK: - Process lifecycle
+
+    private func ensureRunning() async throws {
+        if let process, process.isRunning { return }
+        try await start()
+    }
+
+    private func start() async throws {
+        let process = Process()
+        process.executableURL = URL(fileURLWithPath: "/usr/bin/env")
+        process.arguments = ["pnpm", "clawdis", "rpc"]
+        let projectRoot = await RelayProcessManager.shared.projectRootPath()
+        process.currentDirectoryURL = URL(fileURLWithPath: projectRoot)
+
+        let stdinPipe = Pipe()
+        let stdoutPipe = Pipe()
+        process.standardInput = stdinPipe
+        process.standardOutput = stdoutPipe
+        process.standardError = Pipe()
+
+        try process.run()
+
+        self.process = process
+        self.stdinHandle = stdinPipe.fileHandleForWriting
+        self.stdoutHandle = stdoutPipe.fileHandleForReading
+
+        stdoutPipe.fileHandleForReading.readabilityHandler = { [weak self] handle in
+            guard let self else { return }
+            let data = handle.availableData
+            if data.isEmpty { return }
+            Task { await self.ingest(data: data) }
+        }
+
+        Task.detached { [weak self] in
+            process.waitUntilExit()
+            await self?.stop()
+        }
+    }
+
+    private func stop() async {
+        stdoutHandle?.readabilityHandler = nil
+        process?.terminate()
+        process = nil
+        stdinHandle = nil
+        stdoutHandle = nil
+        buffer.removeAll(keepingCapacity: false)
+        let waiters = self.waiters
+        self.waiters.removeAll()
+        for waiter in waiters {
+            waiter.resume(throwing: RpcError(message: "rpc process stopped"))
+        }
+    }
+
+    private func ingest(data: Data) {
+        buffer.append(data)
+        while let range = buffer.firstRange(of: Data([0x0A])) {
+            let lineData = buffer.subdata(in: buffer.startIndex..<range.lowerBound)
+            buffer.removeSubrange(buffer.startIndex...range.lowerBound)
+            guard let line = String(data: lineData, encoding: .utf8) else { continue }
+            if let waiter = waiters.first {
+                waiters.removeFirst()
+                waiter.resume(returning: line)
+            }
+        }
+    }
+
+    private func nextLine() async throws -> String {
+        try await withCheckedThrowingContinuation { (cont: CheckedContinuation<String, Error>) in
+            waiters.append(cont)
+        }
+    }
+}
diff --git a/apps/macos/Sources/Clawdis/XPCService.swift b/apps/macos/Sources/Clawdis/XPCService.swift
index d31e68de1..e715d8d8b 100644
--- a/apps/macos/Sources/Clawdis/XPCService.swift
+++ b/apps/macos/Sources/Clawdis/XPCService.swift
@@ -71,14 +71,24 @@ final class ClawdisXPCService: NSObject, ClawdisXPCProtocol {
         case let .agent(message, thinking, session):
             let trimmed = message.trimmingCharacters(in: .whitespacesAndNewlines)
             guard !trimmed.isEmpty else { return Response(ok: false, message: "message empty") }
+            let sessionKey = session ?? "main"
+
+            // Try RPC first for lower latency; fall back to one-shot CLI.
+            let rpcResult = await AgentRPC.shared.send(
+                text: trimmed,
+                thinking: thinking,
+                session: sessionKey)
+            if rpcResult.ok {
+                return Response(ok: true, message: rpcResult.text ?? "sent")
+            }
 
             let result = await self.runAgentCLI(
                 message: trimmed,
                 thinking: thinking,
-                session: session ?? "main")
+                session: sessionKey)
             return result.ok
                 ? Response(ok: true, message: result.text ?? "sent")
-                : Response(ok: false, message: result.error ?? "failed to send")
+                : Response(ok: false, message: result.error ?? rpcResult.error ?? "failed to send")
         }
     }