Setting 1 second lifetime for ssh-agent passphrase

gistfile1.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>org.openbsd.ssh-agent</string>
    <key>ProgramArguments</key>
    <array>
        <string>/usr/bin/ssh-agent</string>
        <string>-l</string>
        <string>-t</string>
        <string>1</string>
    </array>
    <key>ServiceIPC</key>
    <true/>
    <key>Sockets</key>
    <dict>
        <key>Listeners</key>
        <dict>
            <key>SecureSocketWithKey</key>
            <string>SSH_AUTH_SOCK</string>
        </dict>
    </dict>
        <key>EnableTransactions</key>
        <true/>
</dict>
</plist>