diff --git a/packages/opencode/src/server/routes/global.ts b/packages/opencode/src/server/routes/global.ts
index 4d019f6a7ee..bc503c11fc0 100644
--- a/packages/opencode/src/server/routes/global.ts
+++ b/packages/opencode/src/server/routes/global.ts
@@ -69,33 +69,51 @@ export const GlobalRoutes = lazy(() =>
         c.header("X-Accel-Buffering", "no")
         c.header("X-Content-Type-Options", "nosniff")
         return streamSSE(c, async (stream) => {
-          stream.writeSSE({
-            data: JSON.stringify({
-              payload: {
-                type: "server.connected",
-                properties: {},
-              },
-            }),
-          })
-          async function handler(event: any) {
-            await stream.writeSSE({
-              data: JSON.stringify(event),
-            })
-          }
-          GlobalBus.on("event", handler)
-
-          // Send heartbeat every 10s to prevent stalled proxy streams.
-          const heartbeat = setInterval(() => {
+          try {
             stream.writeSSE({
               data: JSON.stringify({
                 payload: {
-                  type: "server.heartbeat",
+                  type: "server.connected",
                   properties: {},
                 },
               }),
             })
+          } catch {
+            log.info("global event disconnected (initial write failed)")
+            return
+          }
+
+          // Heartbeat must be declared before handler to avoid confusion
+          const heartbeat = setInterval(() => {
+            try {
+              stream.writeSSE({
+                data: JSON.stringify({
+                  payload: {
+                    type: "server.heartbeat",
+                    properties: {},
+                  },
+                }),
+              })
+            } catch {
+              clearInterval(heartbeat)
+              GlobalBus.off("event", handler)
+              log.info("global event disconnected (heartbeat failed)")
+            }
           }, 10_000)
 
+          async function handler(event: any) {
+            try {
+              await stream.writeSSE({
+                data: JSON.stringify(event),
+              })
+            } catch {
+              clearInterval(heartbeat)
+              GlobalBus.off("event", handler)
+              log.info("global event disconnected (write failed)")
+            }
+          }
+          GlobalBus.on("event", handler)
+
           await new Promise<void>((resolve) => {
             stream.onAbort(() => {
               clearInterval(heartbeat)
diff --git a/packages/opencode/src/server/server.ts b/packages/opencode/src/server/server.ts
index 9fba9c1fe1a..239373e8df9 100644
--- a/packages/opencode/src/server/server.ts
+++ b/packages/opencode/src/server/server.ts
@@ -504,31 +504,49 @@ export namespace Server {
             c.header("X-Accel-Buffering", "no")
             c.header("X-Content-Type-Options", "nosniff")
             return streamSSE(c, async (stream) => {
-              stream.writeSSE({
-                data: JSON.stringify({
-                  type: "server.connected",
-                  properties: {},
-                }),
-              })
-              const unsub = Bus.subscribeAll(async (event) => {
-                await stream.writeSSE({
-                  data: JSON.stringify(event),
-                })
-                if (event.type === Bus.InstanceDisposed.type) {
-                  stream.close()
-                }
-              })
-
-              // Send heartbeat every 10s to prevent stalled proxy streams.
-              const heartbeat = setInterval(() => {
+              try {
                 stream.writeSSE({
                   data: JSON.stringify({
-                    type: "server.heartbeat",
+                    type: "server.connected",
                     properties: {},
                   }),
                 })
+              } catch {
+                log.info("event disconnected (initial write failed)")
+                return
+              }
+
+              // Heartbeat must be declared before subscription to avoid confusion
+              const heartbeat = setInterval(() => {
+                try {
+                  stream.writeSSE({
+                    data: JSON.stringify({
+                      type: "server.heartbeat",
+                      properties: {},
+                    }),
+                  })
+                } catch {
+                  clearInterval(heartbeat)
+                  unsub()
+                  log.info("event disconnected (heartbeat failed)")
+                }
               }, 10_000)
 
+              const unsub = Bus.subscribeAll(async (event) => {
+                try {
+                  await stream.writeSSE({
+                    data: JSON.stringify(event),
+                  })
+                  if (event.type === Bus.InstanceDisposed.type) {
+                    stream.close()
+                  }
+                } catch {
+                  clearInterval(heartbeat)
+                  unsub()
+                  log.info("event disconnected (write failed)")
+                }
+              })
+
               await new Promise<void>((resolve) => {
                 stream.onAbort(() => {
                   clearInterval(heartbeat)