Here is a pretty raw dump of some of the tags that HL uses as allot the new ones that are only documented in the release notes. I have not added 7.3 yet but I wanted to clean this up and release it in a nice way but oh well its something. No where near all of them but its a start at ones I tend to use most often. I would love to get all of these documented into a wiki or something search able. But maybe I will just add it eventually to the FAQ post.
=Helper Tags=
Helper.BonFtNoPre - For class
Helper.DamageUp - Increase Natural Weapon Damage Die size by one
Helper.DamageDown - Decrease Natural Weapon Damage Die size by one
Helper.NatPrimary - Make the natural attack a "Primary" attack.
Helper.NatOverSec - Makes the natural attack into a secondary attack.
Helper.NatTwoHand - Forces the weapon to be treated as a two-handed weapon or 1.5str modifier.
Helper.NatSizeDmg - Tells HL to change the die size based on the current size of the character. When using this set the default damage as if the creature was size Medium.
Helper.NatIgnWeap - bootstrapping a Natural attack with this tag renders it immune to the effects of having a weapon equipped. That is, it will remain a primary attack with weapons.
Helper.TwoWpLight - weapons with this tag count as Light for two weapon fighting but not for any other purpose.
Helper.NoHalfStr - weapons with this tag do Str modifier damage even when equipped in the off hand. This is similar to Double Slice but can be applied to only certain weapons (rather than globally to all weapons). It is currently used for Monks with their Unarmed Strikes.
Helper.NoHandWeap - when added to a weapon, it will no longer count as taking a hand to wield (thus preventing conflict with other equipped weapons). This is used for Barbazu Beards, Bladed Boots, and several new weapons from the Advanced Race Guide.
Helper.NoCureInf - when assigned to a hero it prevents the bootstrapping of the bonus Cure/Inflict spells known for an Oracle. Used for the Purifier oracle archetype.
Helper.BrdPerform - which marks the Bardic performance abilities so that they can be more easily selected in foreach/custom expressions.
Helper.ShowFlurry - This makes the Monks Flurry of Blows display for the weapon.
Helper.Improvised - Marks improvised weapons so they can be found and manipulated.
Helper.HalfProfMe and Helper.HalfProfRn - tags have been added, it causes a weapon to not take nonproficiency penalties for melee or ranged attacks, respectively.
Helper.NoArmor - When added to Armor will set the armor bonus to 0. Partial way to disable armor on a character.
Helper.MatForceMs - Forces Materials to make the Gizmo Masterwork
Helper.NoSelect - ???
Helper.Displace - ???
Helper.NoPick - ???
=Hero Tags=
Hero.MutExArmor - when added to the hero it will increase the natural armor bonus granted by a mutagen by 1 (per tag assigned).
Hero.ProfImpMel and Hero.ProfImpRng - tags have been added, granting proficiency in improvised melee and ranged weapons respectively.
Hero.TwoWepHalf - When applied to the hero, it halves any penalties to attack from two weapon fighting (used for the Thunderstriker fighter archetype).
=Hide Tags=
Hide.Weapon - This will hide a weapon and not have it be displayed.
=Misc Tags=
thing.skipprereq - For bootstrap of feat
=Tag Groups=
ClsDenySp - Like the ClsAllowSp tags, these are applied to a class to modify their allowable spells, but instead of adding a spell this tag group removes it instead.
SpellEff - Allows feats and effects that depend on a certain effect (like the Elemental Focus feat needing appropriate elemental damage) can identify which spells they apply to.
DamageOver - When added to a weapon, that weapon will use another attribute in place of Strength to determine its damage bonus.
DamageOpt - if you want to use the higher of Str or the new attribute for damage.
=Weapon Tags=
wMain.1d6_5
wAttMelee - field, which adds to melee attacks. This stacks with the wAttBonus field (which adds to both melee and ranged attacks).