diff --git a/src/servers/sidecar/claude/user-instance.ts b/src/servers/sidecar/claude/user-instance.ts
index 1b62433f..f435cbe4 100644
--- a/src/servers/sidecar/claude/user-instance.ts
+++ b/src/servers/sidecar/claude/user-instance.ts
@@ -39,9 +39,10 @@ const homeDir =
   dbUser.role === 'Super Admin' ? (process.env.HOME_DIR ?? homedir()) : join(DATA_PATH, email, 'home');
 const globalToolsDir = join(DATA_PATH, 'tools');
 
-// The email_db MCP tool reads one account's SQLite store; use the user's first configured account.
+// The email_db MCP tool reads one account's SQLite store; match the API's choice (first enabled).
 const emailAccounts = await getEmailAccounts(dbUser.id);
-const emailDbRel = join('email_accounts', emailAccounts[0]?.email ?? 'none', 'emails.db');
+const emailAccount = emailAccounts.find((a) => a.enabled) ?? emailAccounts[0];
+const emailDbRel = join('email_accounts', emailAccount?.email ?? 'none', 'emails.db');
 const userToolsDir = join(DATA_PATH, email, 'tools');
 
 // ── Path setup ──