The threshold
The sum of the weights of triggered factors. It is not a percentage and not a probability: the production bot uses 4, the working range is 3–8.
A higher threshold means fewer signals, but each rests on more factors agreeing. A lower one means many signals, more of them random.
The minimum number of cores
Cores are the most reliable factors of the set, and they differ between the two market regimes. In a range they are the Bollinger bands, RSI(2), CCI, the stochastic, support and resistance levels, VWAP. In a trend they are the pullback to EMA21, ADX with DI, a Donchian breakout, the EMA fan and market structure.
The setting requires at least N cores to agree. It cuts off the case where the threshold was reached by secondary factors: the sum is formally enough, but there is nothing solid underneath.
The working range is 3 to 5. Six or more and there will be almost no signals.
How to tune
Change one setting at a time and watch the number of signals in a run. If there are no signals at all, lower the minimum number of cores first and the threshold second: cores cut harder.
Few signals is not automatically bad. It is bad when they are few and no better than they were at a lower threshold.