ATMega328P - minimal programming circuit?
Best thing to do would be to design your programming board to include a 10k ohm pullup on Reset and a 100nF capacitor near the VCC pin of the chip (whether or not you populate them, but you might as well for a manufacturing jig). Some ISP programmers require the chip to be powered separately as well. You do not need any crystal circuitry in place for programming a blank off the line AVR (as they come running off the internal oscillator), but if trying to reprogram a chip that is fused for an external crystal, you will need a comparable crystal and load capacitors in circuit (unless you use a high voltage programming mode).