Tips, Filters & Scoring Reference

Tips, Filters & Scoring Reference

Practical guidance for writing effective AI configs, plus reference tables for move filters, item filters, and score modifiers.

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Tips and Common Pitfalls

1. Use score_bonus for status moves

The number one mistake is creating action priorities for setup or status moves with only bias_multiplier. A status move starts at a base score of approximately 1.0. Even bias_multiplier: 10.0 gives you 10.0, which loses to Earthquake at 100.0. Always add score_bonus for non-damaging actions.

{
  "id": "setup_swords_dance",
  "condition": "q.pokemon.current_hp_percent > 0.7",
  "action_type": "move",
  "move_filter": { "names": ["swordsdance"] },
  "priority": 70,
  "bias_multiplier": 1.5,
  "score_bonus": 80.0
}

Why bias_multiplier Alone Fails

bias_multiplier multiplies the existing score. If the base score is 0 or close to 0 (as it is for status moves), multiplying by any value still gives you approximately 0. Use score_bonus to add a flat value that makes the action competitive with damaging moves.

2. matchup.score vs under_threat

q.matchup.score only considers STAB types and is very coarse (roughly -4 to +4). It often returns 0 for neutral matchups, making conditions like > 0 unreliable.

q.pokemon.under_threat (0.0 to 1.0) is more nuanced — it considers super-effective types, speed comparison, opponent stat boosts, and HP. Prefer q.pokemon.under_threat for setup and switch decisions.

// Less reliable — coarse, often 0 for neutral matchups
"condition": "q.matchup.score > 0"

// More reliable — considers multiple factors
"condition": "q.pokemon.under_threat < 0.3"

3. Rule priority tiers

Rules are evaluated from highest to lowest priority. Put your most important rules at high priority numbers. Here are recommended tiers:

Priority Range	Category	Examples
200+	Hard overrides	Trapped = cannot switch, max boosts = stop boosting
90—100	Critical decisions	Heal at very low HP, priority move for the finish
70—85	Strategic decisions	Setup when safe, Toxic against walls
50—60	Tactical preferences	Coverage bonuses, screen setup
5—20	General scoring	Accuracy, STAB, type effectiveness

Higher Numbers = Higher Priority

A rule with priority 200 is evaluated before a rule with priority 50. Think of priority as “importance” — higher values mean the rule takes precedence.

4. Inheritance rule list behavior

When you specify action_priorities: [...] in a child config, your rules are prepended to the parent’s rules. They do not replace them. Child rules come first and are evaluated first.

If you want to start fresh and discard all inherited rules, use an empty array:

{
  "parent": "smart_trainers:expert",
  "action_priorities": []
}

This clears the parent’s action priorities entirely. The same behavior applies to move_scoring_rules, switch_conditions, and gimmick_rules.

5. Use bias 0.0 to completely prevent an action type

Setting bias_multiplier: 0.0 combined with a high priority is the way to prevent actions entirely:

{
  "id": "never_switch_boosted",
  "condition": "q.pokemon.stat_boosts.atk >= 3",
  "action_type": "switch",
  "priority": 200,
  "bias_multiplier": 0.0
}

This prevents the AI from ever switching out a Pokemon that has +3 or more Attack boosts. The score is multiplied by 0, making it impossible to select.

6. Debug mode

You can enable debug mode to see the AI’s decision process in chat. All scores, rule matches, and final rankings are printed for each turn. This is invaluable when tuning AI configs — you can see exactly why the AI chose a particular action and which rules fired.

7. Showdown move ID format

When using "names" or "move_ids" in move filters, use Showdown-format IDs: lowercase, no spaces, no hyphens.

Move Name	Showdown ID
Swords Dance	swordsdance
Dragon Dance	dragondance
Will-O-Wisp	willowisp
U-turn	uturn
Volt Switch	voltswitch

Common Mistake

Writing "Swords Dance" or "swords-dance" in a move filter will not match anything. Always use the Showdown format: "swordsdance".

8. MoLang syntax basics

MoLang is the expression language used for all conditions in Smart Trainers configs. Here is a quick reference:

// Comparison operators
q.pokemon.current_hp_percent < 0.5    // less than
q.pokemon.current_hp_percent > 0.5    // greater than
q.pokemon.current_hp_percent == 0.5   // equal
q.pokemon.current_hp_percent >= 0.5   // greater or equal
q.pokemon.current_hp_percent <= 0.5   // less or equal

// Logical operators
q.pokemon.current_hp_percent < 0.5 && q.target.has_status == 0   // AND
q.pokemon.current_hp_percent < 0.3 || q.pokemon.has_status       // OR
!q.target.has_status                                               // NOT

// Boolean values: 0 = false, anything > 0 = true
// So q.target.has_status alone works as a boolean check

// Math
q.move.power * q.move.type_effectiveness
q.pokemon.current_hp_percent * 100
q.target.current_hp_percent * 2.5

// Function calls (parentheses)
q.pokemon.has_type('fire')
q.pokemon.has_move('earthquake')
q.target.has_revealed_ability('levitate')

// Constant true condition
"condition": "1"

Null Coalescing

MoLang supports ?? for null coalescing. This is useful with temporary variables: t.my_var = (t.my_var ?? 0) + 1 initializes t.my_var to 0 on first use, then increments it each turn.

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Move Filters

Move filters are used in action_priorities and gimmick_rules to target specific moves. All fields are optional — omitting a field means “match any.”

{
  "move_filter": {
    "categories": ["heal", "buff"],
    "types": ["fire", "water"],
    "names": ["swordsdance", "dragondance"],
    "move_ids": ["earthquake"],
    "condition": "q.move.power > 80"
  }
}

Field	Type	Description
categories	string[]	Match moves with any of these AI categories.
types	string[]	Match moves of any of these elemental types.
names	string[]	Match specific move names (Showdown IDs).
move_ids	string[]	Same as names — both are checked.
condition	Molang	Additional Molang condition. Gives access to q.move.* queries.

Filter Logic

When multiple fields are specified, all fields must match (AND logic). Within a single field, any value matches (OR logic). For example, \{"categories": ["heal", "buff"], "types": ["fire"]\} matches moves that are (heal OR buff) AND (fire type).

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Item Filters

Item filters are used in usageRules within battle bag configs to target specific items.

{
  "itemFilter": {
    "categories": ["HEALING"],
    "items": ["cobblemon:full_restore"]
  }
}

Field	Type	Description
categories	string[]	Match items with any of these categories.
items	string[]	Match specific item IDs.
condition	Molang	Additional Molang condition.

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Score Modifiers

Score modifiers are used in move_scoring_rules. Each rule has a score_modifier with a type and value. The value field is always a Molang expression, so it can reference queries dynamically.

Type	Behavior	Example
multiply	new_score = old_score * value	\{"type": "multiply", "value": "1.5"\}
add	new_score = old_score + value	\{"type": "add", "value": "50"\}
set	new_score = value (ignores old score)	\{"type": "set", "value": "0"\}
script	new_score = value (Molang expression returns the final value)	\{"type": "script", "value": "q.move.power * q.move.type_effectiveness"\}

Because the value field is a Molang expression, you can write dynamic modifiers:

{
  "type": "multiply",
  "value": "q.move.type_effectiveness"
}

This multiplies the move’s score by its type effectiveness (2.0 for super effective, 0.5 for not very effective, etc.).