fix: restore remote OpenCode providers and startup errors

- Fix OpenChamber proxying to the correct OpenCode host for remote VPS setups
- Show a clear empty-state error when OpenCode is not reachable
- Harden session event routing for early or mismatched directory events

packages/ui/src/components/chat/ChatEmptyState.tsx

@@ -1,16 +1,27 @@
 import React from 'react';
 import { OpenChamberLogo } from '@/components/ui/OpenChamberLogo';
 import { useThemeSystem } from '@/contexts/useThemeSystem';
+import { useGlobalSyncStore } from '@/sync/global-sync-store';
 
 const ChatEmptyState: React.FC = () => {
     const { currentTheme } = useThemeSystem();
+    const initError = useGlobalSyncStore((s) => s.error);
 
     const textColor = currentTheme?.colors?.surface?.mutedForeground || 'var(--muted-foreground)';
 
     return (
         <div className="flex flex-col items-center justify-center min-h-full w-full gap-6">
             <OpenChamberLogo width={140} height={140} className="opacity-20" />
-            <span className="text-body-md" style={{ color: textColor }}>Start a new chat</span>
+            {initError ? (
+                <div className="flex flex-col items-center gap-2 max-w-md text-center px-4">
+                    <span className="text-body-md font-medium text-destructive">OpenCode is not reachable</span>
+                    <span className="text-body-sm" style={{ color: textColor }}>
+                        {initError.message}
+                    </span>
+                </div>
+            ) : (
+                <span className="text-body-md" style={{ color: textColor }}>Start a new chat</span>
+            )}
         </div>
     );
 };

packages/ui/src/sync/bootstrap.ts

@@ -50,7 +50,27 @@ export async function bootstrapGlobal(
     console.error("[bootstrap] global bootstrap failed", errors[0])
   }
 
-  set({ ready: true })
+  // If ALL requests failed, OpenCode is likely down — fetch the OpenChamber
+  // health endpoint (outside the readiness gate) to get the actual error reason.
+  if (errors.length === results.length) {
+    let message = errors[0] instanceof Error ? errors[0].message : String(errors[0])
+    try {
+      const healthRes = await fetch("/health", { signal: AbortSignal.timeout(4000) })
+      if (healthRes.ok) {
+        const health = await healthRes.json()
+        if (health.lastOpenCodeError) {
+          message = health.lastOpenCodeError
+        } else if (!health.openCodeRunning) {
+          message = "OpenCode process is not running"
+        }
+      }
+    } catch {
+      // health endpoint itself unreachable — use the original error
+    }
+    set({ ready: true, error: { type: "init", message } })
+  } else {
+    set({ ready: true, error: undefined })
+  }
 }
 
 // ---------------------------------------------------------------------------

packages/ui/src/sync/session-actions.ts

@@ -11,6 +11,7 @@ import type { DirectoryStore } from "./child-store"
 import type { StoreApi } from "zustand"
 import { opencodeClient } from "@/lib/opencode/client"
 import { useGlobalSessionsStore } from "@/stores/useGlobalSessionsStore"
+import { registerSessionDirectory } from "./sync-refs"
 
 // Reference set by SyncProvider — allows actions to access SDK and stores
 let _sdk: OpencodeClient | null = null
@@ -93,6 +94,11 @@ export async function createSession(
     if (!session) return null
 
       const sessionDirectory = (session as { directory?: string }).directory ?? directoryOverride ?? null
+      // Pre-populate routing index so SSE events arriving before session.created
+      // can be routed to the correct child store
+      if (sessionDirectory) {
+        registerSessionDirectory(session.id, sessionDirectory)
+      }
       useSessionUIStore.getState().setCurrentSession(session.id, sessionDirectory)
       useSessionUIStore.getState().markSessionAsOpenChamberCreated(session.id)
       useGlobalSessionsStore.getState().upsertSession(session)

packages/ui/src/sync/sync-context.tsx

@@ -194,7 +194,9 @@ const normalizeEventDirectory = (rawDirectory: string): string => {
   if (!rawDirectory || rawDirectory === "global") {
     return rawDirectory
   }
-  return rawDirectory.replace(/\\/g, "/").replace(/^([a-z]):/, (_, l: string) => l.toUpperCase() + ":")
+  const normalized = rawDirectory.replace(/\\/g, "/").replace(/^([a-z]):/, (_, l: string) => l.toUpperCase() + ":")
+  // Strip trailing slashes to match child store keys (normalizeDirectoryPath in useDirectoryStore)
+  return normalized.length > 1 ? normalized.replace(/\/+$/, "") : normalized
 }
 
 const getSessionIdFromPayload = (event: Event): string | null => {
@@ -419,6 +421,26 @@ const ingestDirectoryStateIntoRoutingIndex = (
   }
 }
 
+const findSessionInChildStores = (
+  sessionID: string,
+  childStores: ChildStoreManager,
+  routingIndex: EventRoutingIndex,
+): string | null => {
+  for (const [dir, store] of childStores.children) {
+    const state = store.getState()
+    if (
+      state.session.some((s) => s.id === sessionID)
+      || Object.prototype.hasOwnProperty.call(state.message, sessionID)
+      || Object.prototype.hasOwnProperty.call(state.session_status ?? {}, sessionID)
+    ) {
+      // Self-heal: populate the routing index so future events resolve instantly
+      setIndexedSessionDirectory(routingIndex, sessionID, dir)
+      return dir
+    }
+  }
+  return null
+}
+
 const resolveDirectoryFromRoutingIndex = (
   routingIndex: EventRoutingIndex,
   rawDirectory: string,
@@ -433,6 +455,13 @@ const resolveDirectoryFromRoutingIndex = (
     if (indexedDirectory) {
       return indexedDirectory
     }
+
+    // Routing index miss — scan child stores for this session.
+    // Covers optimistic sessions not yet indexed and events with wrong/empty directory.
+    const found = findSessionInChildStores(sessionID, childStores, routingIndex)
+    if (found) {
+      return found
+    }
   }
 
   const messageID = getMessageIdFromPayload(payload)
@@ -444,8 +473,16 @@ const resolveDirectoryFromRoutingIndex = (
         return indexedDirectory
       }
     }
+
+    // Scan child stores for a store that has parts for this message
+    for (const [dir, store] of childStores.children) {
+      if (Object.prototype.hasOwnProperty.call(store.getState().part, messageID)) {
+        return dir
+      }
+    }
   }
 
+  // Single-store fallback: if there's only one directory, use it
   if (
     (sessionID || messageID)
     && (!normalizedDirectory || normalizedDirectory === "global")
@@ -653,7 +690,22 @@ function handleEvent(
   }
 
   // Directory events
-  const store = childStores.getChild(directory)
+  let store = childStores.getChild(directory)
+  let resolvedDirectory = directory
+
+  if (!store) {
+    // Store not found for this directory — attempt recovery by scanning
+    // child stores for the session. This handles directory mismatches
+    // (trailing slashes, case differences, events with wrong directory).
+    const sessionID = getSessionIdFromPayload(payload)
+    if (sessionID) {
+      const fallbackDir = findSessionInChildStores(sessionID, childStores, routingIndex)
+      if (fallbackDir) {
+        store = childStores.getChild(fallbackDir)
+        resolvedDirectory = fallbackDir
+      }
+    }
+  }
 
   if (!store) {
     // Try as global event for unknown directories
@@ -669,7 +721,7 @@ function handleEvent(
     return
   }
 
-  childStores.mark(directory)
+  childStores.mark(resolvedDirectory)
 
   // Notification dispatch for session turn-complete and error events.
   // These are NOT handled by the event reducer — only the notification store.
@@ -683,10 +735,10 @@ function handleEvent(
       // subtask — skip notification
     } else if (sessionID) {
       appendNotification({
-        directory,
+        directory: resolvedDirectory,
         session: sessionID,
         time: Date.now(),
-        viewed: isViewedInCurrentSession(directory, sessionID),
+        viewed: isViewedInCurrentSession(resolvedDirectory, sessionID),
         ...(payload.type === "session.error"
           ? { type: "error" as const, error: props.error }
           : { type: "turn-complete" as const }),
@@ -752,7 +804,7 @@ function handleEvent(
     store.setState(draft)
   }
 
-  updateRoutingIndexFromEvent(routingIndex, directory, payload)
+  updateRoutingIndexFromEvent(routingIndex, resolvedDirectory, payload)
 
   // Update global session status for cross-directory sidebar visibility
   if (payload.type === "session.status") {
@@ -761,15 +813,15 @@ function handleEvent(
   }
 
   if (payload.type === "permission.asked") {
-    const normalizedDirectory = normalizeDirectory(directory)
+    const nd = normalizeDirectory(resolvedDirectory)
-    if (!normalizedDirectory) {
+    if (!nd) {
       return
     }
 
     const permission = payload.properties as PermissionRequest
     const sessions = store.getState().session
     const autoAccept = usePermissionStore.getState().autoAccept
-    if (autoRespondsPermission({ autoAccept, sessions, sessionID: permission.sessionID, directory: normalizedDirectory })) {
+    if (autoRespondsPermission({ autoAccept, sessions, sessionID: permission.sessionID, directory: nd })) {
       void sessionActions.respondToPermission(permission.sessionID, permission.id, "once").catch(() => undefined)
     }
   }
@@ -928,13 +980,15 @@ export function SyncProvider(props: {
 
   // Set refs so non-React code (session-actions, session-ui-store) can access sync state
   useEffect(() => {
-    setSyncRefs(props.sdk, childStores, props.directory)
+    setSyncRefs(props.sdk, childStores, props.directory, (sessionID, dir) => {
+      setIndexedSessionDirectory(routingIndex, sessionID, dir)
+    })
     setActionRefs(
       props.sdk,
       childStores,
       () => opencodeClient.getDirectory() || props.directory,
     )
-  }, [props.sdk, props.directory, childStores])
+  }, [props.sdk, props.directory, childStores, routingIndex])
 
   // Subscribe to child store for streaming state derivation
   useEffect(() => {

packages/ui/src/sync/sync-refs.ts

@@ -12,15 +12,27 @@ import type { State } from "./types"
 let _sdk: OpencodeClient | null = null
 let _childStores: ChildStoreManager | null = null
 let _directory: string = ""
+let _registerSessionDirectory: ((sessionID: string, directory: string) => void) | null = null
 
 export function setSyncRefs(
   sdk: OpencodeClient,
   childStores: ChildStoreManager,
   directory: string,
+  registerSessionDirectory?: (sessionID: string, directory: string) => void,
 ) {
   _sdk = sdk
   _childStores = childStores
   _directory = directory
+  if (registerSessionDirectory) {
+    _registerSessionDirectory = registerSessionDirectory
+  }
+}
+
+/** Pre-register a session→directory mapping in the routing index.
+ *  Called from session-actions when creating sessions so SSE events
+ *  arriving before session.created can be routed correctly. */
+export function registerSessionDirectory(sessionID: string, directory: string) {
+  _registerSessionDirectory?.(sessionID, directory)
 }
 
 export function getSyncSDK(): OpencodeClient {

packages/web/server/lib/opencode/lifecycle.js

@@ -204,7 +204,7 @@ export const createOpenCodeLifecycleRuntime = (deps) => {
     }
 
     try {
-      const response = await fetch(`http://127.0.0.1:${state.openCodePort}/session`, {
+      const response = await fetch(buildOpenCodeUrl('/session', ''), {
         method: 'GET',
         headers: getOpenCodeAuthHeaders(),
         signal: AbortSignal.timeout(2000),

packages/web/server/lib/opencode/proxy.js

@@ -31,6 +31,45 @@ export const registerOpenCodeProxy = (app, deps) => {
   app.set('opencodeProxyConfigured', true);
 
   const isAbortError = (error) => error?.name === 'AbortError';
+  const FALLBACK_PROXY_TARGET = 'http://127.0.0.1:3902';
+
+  const normalizeProxyTarget = (candidate) => {
+    if (typeof candidate !== 'string') {
+      return null;
+    }
+
+    const trimmed = candidate.trim();
+    if (!trimmed) {
+      return null;
+    }
+
+    return trimmed.replace(/\/+$/, '');
+  };
+
+  // Keep generic proxy requests on the same upstream base URL that health checks
+  // and direct fetch helpers use. This avoids split-brain state where /health
+  // succeeds against an external host but /api/* still proxies to 127.0.0.1.
+  const resolveProxyTarget = () => {
+    try {
+      const resolved = normalizeProxyTarget(buildOpenCodeUrl('/', ''));
+      if (resolved) {
+        return resolved;
+      }
+    } catch {
+    }
+
+    const runtimeState = getRuntime();
+    const externalBase = normalizeProxyTarget(runtimeState.openCodeBaseUrl);
+    if (externalBase) {
+      return externalBase;
+    }
+
+    if (runtimeState.openCodePort) {
+      return `http://localhost:${runtimeState.openCodePort}`;
+    }
+
+    return FALLBACK_PROXY_TARGET;
+  };
 
   const forwardSseRequest = async (req, res) => {
     const abortController = new AbortController();
@@ -79,6 +118,12 @@ export const registerOpenCodeProxy = (app, deps) => {
         res.flushHeaders();
       }
 
+      // Disable TCP Nagle's algorithm so small SSE chunks are sent immediately
+      // instead of being buffered up to ~200ms by the TCP stack.
+      if (res.socket && typeof res.socket.setNoDelay === 'function') {
+        res.socket.setNoDelay(true);
+      }
+
       reader = upstream.body.getReader();
       while (!abortController.signal.aborted) {
         const { done, value } = await reader.read();
@@ -233,14 +278,11 @@ export const registerOpenCodeProxy = (app, deps) => {
 
   // Generic proxy for non-SSE OpenCode API routes.
   const apiProxy = createProxyMiddleware({
-    target: `http://127.0.0.1:${runtime.openCodePort || 3902}`,
+    target: resolveProxyTarget(),
     changeOrigin: true,
     pathRewrite: { '^/api': '' },
     // Dynamic target — port can change after restart
-    router: () => {
+    router: () => resolveProxyTarget(),
-      const rt = getRuntime();
-      return `http://127.0.0.1:${rt.openCodePort || 3902}`;
-    },
     on: {
       proxyReq: (proxyReq) => {
         // Inject OpenCode auth headers