hoi4-mtth

name	hoi4-mtth
description	Define and use HOI4 MTTH variables safely (base/modifiers, file-scoped constants, and mtth:entry usage in set_variable/set_temp_variable) with guidance for minimizing ai_will_do clutter.

HOI4 MTTH Variables

Scope and References

Use MTTH variables to compute a value from a base plus modifiers, then inject that value into other logic.

Read existing repository MTTH files first if the mod already has them. Otherwise use common/mtth/*.txt as the standard location.

Defining an MTTH entry

Create entries in common/mtth/*.txt:

example_mtth_value = {
	base = 50

	modifier = {
		factor = 0.8
		tag = GER
	}
	modifier = {
		add = 25
		has_war = yes
	}
}

Notes:

• base is the starting value.
• modifier blocks use factor or add and standard triggers.

Using an MTTH entry

Vanilla example pattern:

set_variable = { my_value = mtth:example_mtth_value }

Typical usage:

• set_variable or set_temp_variable to store the computed MTTH value.
• Use the variable later (add = temp, check_variable = { temp > 1 }, etc.).

AI weights with MTTH

To reduce ai_will_do clutter, compute the full weight in MTTH and inject it:

ai_will_do = {
	factor = 0
	modifier = {
		set_temp_variable = { temp = mtth:chem_ai_weight }
		add = temp
	}
}

Scenario analysis

Use hoi4.probability_inspect to identify the MTTH entry, modifiers, helpers, and scenario inputs before evaluating timing. Use hoi4.probability_evaluate for named world states, hoi4.probability_sweep for thresholds and timing reversals, hoi4.probability_simulate for declared uncertain inputs, and hoi4.probability_compare after a patch. Use hoi4.probability_render for timing-survival, sensitivity, comparison, and unresolved views when visual evidence is clearer. Supply scheduled state changes when conditions vary across the horizon. Accept cumulative timing only from the verified game-version MTTH adapter, and keep exact, bounded, sampled, and unresolved results distinct. The analyzer supplies evidence and never chooses the intended timing or writes source.