diff --git a/dist/index.d.ts b/dist/index.d.ts
index 68c5c5b..fc4f1c0 100644
--- a/dist/index.d.ts
+++ b/dist/index.d.ts
@@ -625,7 +625,6 @@ declare const REACTION_TIME: {
 };
 
 declare const BOOSTS: {
-    [part: string]: { [boost: string]: { [action: string]: number } };
     work: {
         UO: {
             harvest: 3;
@@ -739,7 +738,7 @@ declare const BOOSTS: {
             damage: 0.3;
         };
     };
-};
+} & Record<BodyPartConstant, Record<MineralBoostConstant, Record<BoostModifier, number>>>;
 
 declare const INTERSHARD_RESOURCES: InterShardResourceConstant[];
 
@@ -1746,7 +1745,7 @@ type BodyPartDefinition<T extends BodyPartConstant = BodyPartConstant> = T exten
            *
            * If the body part is boosted, this property specifies the mineral type which is used for boosting.
            */
-          boost?: keyof (typeof BOOSTS)[T];
+          boost?: keyof typeof BOOSTS[T];
           /**
            * One of the body part types constants.
            */
@@ -2777,6 +2776,21 @@ type EffectConstant = EFFECT_INVULNERABILITY | EFFECT_COLLAPSE_TIMER;
 
 type EFFECT_INVULNERABILITY = 1001;
 type EFFECT_COLLAPSE_TIMER = 1002;
+
+type BoostModifier =
+    | "harvest"
+    | "build"
+    | "repair"
+    | "dismantle"
+    | "upgradeController"
+    | "attack"
+    | "rangedAttack"
+    | "rangedMassAttack"
+    | "heal"
+    | "rangedHeal"
+    | "capacity"
+    | "fatigue"
+    | "damage";
 /**
  * The options that can be accepted by `findRoute()` and friends.
  */
diff --git a/dist/screeps-tests.ts b/dist/screeps-tests.ts
index 27af63d..93406fc 100644
--- a/dist/screeps-tests.ts
+++ b/dist/screeps-tests.ts
@@ -1201,7 +1201,7 @@ function atackPower(creep: Creep) {
     return creep.body
         .map((part) => {
             if (part.type === ATTACK) {
-                const multiplier = part.boost ? BOOSTS[part.type][part.boost].attack : 1;
+                const multiplier = part.boost ? BOOSTS[part.type][part.boost]?.attack ?? 0 : 1;
                 return multiplier * ATTACK_POWER;
             }
             return 0;
diff --git a/src/constants.ts b/src/constants.ts
index edfe468..df4320a 100644
--- a/src/constants.ts
+++ b/src/constants.ts
@@ -610,7 +610,6 @@ declare const REACTION_TIME: {
 };
 
 declare const BOOSTS: {
-    [part: string]: { [boost: string]: { [action: string]: number } };
     work: {
         UO: {
             harvest: 3;
@@ -724,7 +723,7 @@ declare const BOOSTS: {
             damage: 0.3;
         };
     };
-};
+} & Record<BodyPartConstant, Record<MineralBoostConstant, Record<BoostModifier, number>>>;
 
 declare const INTERSHARD_RESOURCES: InterShardResourceConstant[];
 
diff --git a/src/helpers.ts b/src/helpers.ts
index 62519b7..919c548 100644
--- a/src/helpers.ts
+++ b/src/helpers.ts
@@ -147,7 +147,7 @@ type BodyPartDefinition<T extends BodyPartConstant = BodyPartConstant> = T exten
            *
            * If the body part is boosted, this property specifies the mineral type which is used for boosting.
            */
-          boost?: keyof (typeof BOOSTS)[T];
+          boost?: keyof typeof BOOSTS[T];
           /**
            * One of the body part types constants.
            */
diff --git a/src/literals.ts b/src/literals.ts
index 53ac152..6c237be 100644
--- a/src/literals.ts
+++ b/src/literals.ts
@@ -700,3 +700,18 @@ type EffectConstant = EFFECT_INVULNERABILITY | EFFECT_COLLAPSE_TIMER;
 
 type EFFECT_INVULNERABILITY = 1001;
 type EFFECT_COLLAPSE_TIMER = 1002;
+
+type BoostModifier =
+    | "harvest"
+    | "build"
+    | "repair"
+    | "dismantle"
+    | "upgradeController"
+    | "attack"
+    | "rangedAttack"
+    | "rangedMassAttack"
+    | "heal"
+    | "rangedHeal"
+    | "capacity"
+    | "fatigue"
+    | "damage";