diff --git a/apps/server/src/main/kotlin/com/correx/apps/server/ws/GlobalStreamHandler.kt b/apps/server/src/main/kotlin/com/correx/apps/server/ws/GlobalStreamHandler.kt
index 6fc2a38d..f686708d 100644
--- a/apps/server/src/main/kotlin/com/correx/apps/server/ws/GlobalStreamHandler.kt
+++ b/apps/server/src/main/kotlin/com/correx/apps/server/ws/GlobalStreamHandler.kt
@@ -192,6 +192,35 @@ class GlobalStreamHandler(private val module: ServerModule) {
         }
         val sessionId: SessionId = TypeId(UUID.randomUUID().toString())
         log.info("starting session={} workflow={}", sessionId.value, msg.workflowId)
+
+        // Send protocol messages FIRST. If the WS is already closed, these throw and the
+        // orchestrator never launches — no silent data loss. The exception propagates to the
+        // runCatching in handleClientMessage (caller) and is logged there.
+        val started = ServerMessage.SessionStarted(
+            sessionId = sessionId,
+            workflowId = msg.workflowId,
+            sequence = 0L,
+            sessionSequence = 0L,
+        )
+        session.send(Frame.Text(ProtocolSerializer.encodeServerMessage(started)))
+
+        val stages = graph.stages.map { (stageId, stageConfig) ->
+            val tools = stageConfig.allowedTools.mapNotNull { toolName ->
+                module.toolRegistry.resolve(toolName)?.let { tool ->
+                    ToolDecl(name = tool.name, tier = tool.tier.level)
+                }
+            }
+            StageToolDecl(stageId = stageId.value, tools = tools)
+        }
+        session.send(Frame.Text(ProtocolSerializer.encodeServerMessage(
+            ServerMessage.StageToolManifest(
+                sessionId = sessionId,
+                workflowId = msg.workflowId,
+                stages = stages,
+            ),
+        )))
+
+        // Only launch orchestrator after protocol messages are delivered successfully
         module.moduleScope.launch {
             runCatching { module.orchestrator.run(sessionId, graph, module.defaultOrchestrationConfig) }
                 .onFailure { ex ->
@@ -216,35 +245,6 @@ class GlobalStreamHandler(private val module: ServerModule) {
                     )
                 }
         }
-
-        runCatching {
-            val started = ServerMessage.SessionStarted(
-                sessionId = sessionId,
-                workflowId = msg.workflowId,
-                sequence = 0L,
-                sessionSequence = 0L,
-            )
-            session.send(Frame.Text(ProtocolSerializer.encodeServerMessage(started)))
-
-            // Emit StageToolManifest for the newly created session (ARCH-TOOL-1)
-            val stages = graph.stages.map { (stageId, stageConfig) ->
-                val tools = stageConfig.allowedTools.mapNotNull { toolName ->
-                    module.toolRegistry.resolve(toolName)?.let { tool ->
-                        ToolDecl(name = tool.name, tier = tool.tier.level)
-                    }
-                }
-                StageToolDecl(stageId = stageId.value, tools = tools)
-            }
-            session.send(Frame.Text(ProtocolSerializer.encodeServerMessage(
-                ServerMessage.StageToolManifest(
-                    sessionId = sessionId,
-                    workflowId = msg.workflowId,
-                    stages = stages,
-                ),
-            )))
-        }.onFailure { ex ->
-            log.warn("failed to send session start messages for session={}: {}", sessionId.value, ex.message)
-        }
     }
 }