diff --git a/packages/vscode/src/AgentManagerPanelProvider.ts b/packages/vscode/src/AgentManagerPanelProvider.ts
index 842800af..70900ebd 100644
--- a/packages/vscode/src/AgentManagerPanelProvider.ts
+++ b/packages/vscode/src/AgentManagerPanelProvider.ts
@@ -6,12 +6,13 @@ import { getWebviewShikiThemes } from './shikiThemes';
 import { getWebviewHtml } from './webviewHtml';
 import { openSseProxy } from './sseProxy';
 import { resolveWebviewDevServerUrl } from './webviewDevServer';
+import { normalizeWindowsDriveLetter } from './pathUtils';
 
 export class AgentManagerPanelProvider {
   public static readonly viewType = 'openchamber.agentManager';
 
   private _panel?: vscode.WebviewPanel;
-  
+
   // Cache latest status/URL for when webview is resolved after connection is ready
   private _cachedStatus: ConnectionStatus = 'connecting';
   private _cachedError?: string;
@@ -54,10 +55,10 @@ export class AgentManagerPanelProvider {
     };
 
     this._panel.webview.html = this._getHtmlForWebview(this._panel.webview);
-    
+
     // Send theme payload (including optional Shiki theme JSON) after the webview is set up.
     void this.updateTheme(vscode.window.activeColorTheme.kind);
-    
+
     // Send cached connection status
     this._sendCachedState();
 
@@ -115,16 +116,16 @@ export class AgentManagerPanelProvider {
     // Cache the latest state
     this._cachedStatus = status;
     this._cachedError = error;
-    
+
     // Send to webview if it exists
     this._sendCachedState();
   }
-  
+
   private _sendCachedState() {
     if (!this._panel) {
       return;
     }
-    
+
     this._panel.webview.postMessage({
       type: 'connectionStatus',
       status: this._cachedStatus,
@@ -221,7 +222,9 @@ export class AgentManagerPanelProvider {
   }
 
   private _getHtmlForWebview(webview: vscode.Webview): string {
-    const workspaceFolder = vscode.workspace.workspaceFolders?.[0]?.uri.fsPath || '';
+    const workspaceFolder = normalizeWindowsDriveLetter(
+      vscode.workspace.workspaceFolders?.[0]?.uri.fsPath || ''
+    );
     const cliAvailable = this._openCodeManager?.isCliAvailable() ?? false;
 
     return getWebviewHtml({
diff --git a/packages/vscode/src/ChatViewProvider.ts b/packages/vscode/src/ChatViewProvider.ts
index 84b65869..c30c6fda 100644
--- a/packages/vscode/src/ChatViewProvider.ts
+++ b/packages/vscode/src/ChatViewProvider.ts
@@ -6,6 +6,7 @@ import { getWebviewShikiThemes } from './shikiThemes';
 import { getWebviewHtml } from './webviewHtml';
 import { openSseProxy } from './sseProxy';
 import { resolveWebviewDevServerUrl } from './webviewDevServer';
+import { normalizeWindowsDriveLetter } from './pathUtils';
 
 export class ChatViewProvider implements vscode.WebviewViewProvider {
   public static readonly viewType = 'openchamber.chatView';
@@ -392,7 +393,9 @@ export class ChatViewProvider implements vscode.WebviewViewProvider {
   }
 
   private _getHtmlForWebview(webview: vscode.Webview) {
-    const workspaceFolder = vscode.workspace.workspaceFolders?.[0]?.uri.fsPath || '';
+    const workspaceFolder = normalizeWindowsDriveLetter(
+      vscode.workspace.workspaceFolders?.[0]?.uri.fsPath || ''
+    );
     // Use cached values which are updated by onStatusChange callback
     const initialStatus = this._cachedStatus;
     const cliAvailable = this._openCodeManager?.isCliAvailable() ?? false;
diff --git a/packages/vscode/src/SessionEditorPanelProvider.ts b/packages/vscode/src/SessionEditorPanelProvider.ts
index d0cf53c3..d6377027 100644
--- a/packages/vscode/src/SessionEditorPanelProvider.ts
+++ b/packages/vscode/src/SessionEditorPanelProvider.ts
@@ -6,6 +6,7 @@ import { getWebviewShikiThemes } from './shikiThemes';
 import { getWebviewHtml } from './webviewHtml';
 import { openSseProxy } from './sseProxy';
 import { resolveWebviewDevServerUrl } from './webviewDevServer';
+import { normalizeWindowsDriveLetter } from './pathUtils';
 
 type SessionPanelState = {
   panel: vscode.WebviewPanel;
@@ -257,7 +258,9 @@ export class SessionEditorPanelProvider {
   }
 
   private _getHtmlForWebview(webview: vscode.Webview, sessionId: string | null) {
-    const workspaceFolder = vscode.workspace.workspaceFolders?.[0]?.uri.fsPath || '';
+    const workspaceFolder = normalizeWindowsDriveLetter(
+      vscode.workspace.workspaceFolders?.[0]?.uri.fsPath || ''
+    );
     const initialStatus = this._cachedStatus;
     const cliAvailable = this._openCodeManager?.isCliAvailable() ?? false;
 
diff --git a/packages/vscode/src/opencode.ts b/packages/vscode/src/opencode.ts
index dd628ff5..aa1b652a 100644
--- a/packages/vscode/src/opencode.ts
+++ b/packages/vscode/src/opencode.ts
@@ -7,6 +7,7 @@ import { execSync } from 'child_process';
 import { spawnSync } from 'child_process';
 import { spawn } from 'child_process';
 import { randomBytes } from 'crypto';
+import { normalizeWindowsDriveLetter } from './pathUtils';
 
 const READY_CHECK_TIMEOUT_MS = 30000;
 export type ConnectionStatus = 'disconnected' | 'connecting' | 'connected' | 'error';
@@ -626,11 +627,6 @@ export function createOpenCodeManager(_context: vscode.ExtensionContext): OpenCo
   let status: ConnectionStatus = 'disconnected';
   let lastError: string | undefined;
   const listeners = new Set<(status: ConnectionStatus, error?: string) => void>();
-  /** On Windows, VS Code's uri.fsPath returns a lowercase drive letter (e.g. d:\...)
-   *  while process.cwd() (used by OpenCode server) returns uppercase (D:\...).
-   *  Normalize to uppercase so session directory queries match. */
-  const normalizeWindowsDriveLetter = (p: string): string =>
-    p.replace(/^([a-z]):/, (_, letter: string) => letter.toUpperCase() + ':');
   const workspaceDirectory = (): string =>
     normalizeWindowsDriveLetter(vscode.workspace.workspaceFolders?.[0]?.uri.fsPath || os.homedir());
   let workingDirectory: string = workspaceDirectory();
diff --git a/packages/vscode/src/pathUtils.ts b/packages/vscode/src/pathUtils.ts
new file mode 100644
index 00000000..85245a9d
--- /dev/null
+++ b/packages/vscode/src/pathUtils.ts
@@ -0,0 +1,9 @@
+/**
+ * Normalize Windows drive letter to uppercase.
+ *
+ * VS Code's `workspaceFolders[0].uri.fsPath` returns lowercase drive letters (e.g. `d:\...`),
+ * while process.cwd() (used by OpenCode server) returns uppercase (e.g. `D:\...`).
+ * Normalize to uppercase so session directory queries match.
+ */
+export const normalizeWindowsDriveLetter = (p: string): string =>
+  p.replace(/^([a-z]):/, (_, letter: string) => letter.toUpperCase() + ':');