truestrike is not melee only in PHB, but shows as melee in DnDBeyond

In D&D Beyond, truestrike as the "Attack/Save" field listed as melee.

The original printing of this spell in PHP and SRD do not mention melee anywhere in the RULES TEXT. Spells like booming blade do call out melee.

Is this just an oversight because the field "Attack/Save" can only support one value? 

Is the spell intended to work both ways (based on original rules text it should)

Same thing with Shillelagh. It says "Melee" but the spell itself is not a Melee attack...or ANY attack at all.

While I understand the intent, some people assume this restricts the spells mode or way its executed. I think WotC should improve/clarify these 'extra' fields.

Our DM insists that the addition of melee under the "attack/save" feature actually makes it a rule. He says that because dndbeyond is the official toolset, it does represent the actual rules (and it rolls out eratta and such). We disagree. Is there any source you can point us to that shows this is a data entry error or otherwise incorrect (beyond the plain text in the PHB, which has obviously not been the subject of errata)? 

Quote from J_Michael_Hamilton >>

Our DM insists that the addition of melee under the "attack/save" feature actually makes it a rule. He says that because dndbeyond is the official toolset, it does represent the actual rules (and it rolls out eratta and such). We disagree. Is there any source you can point us to that shows this is a data entry error or otherwise incorrect (beyond the plain text in the PHB, which has obviously not been the subject of eratta)? 

 Your DM is incorrect—the final source of truth is what's in the books. There's no other source for that, but your right that there's been no errata. 

I concur, but he can dig in and prove a bit stubborn. Would love a source I could point him to that says exactly this - the rules are in the published (digital or print) books + errata and not the toolset.

Yeah, that's where we started. Pages and pages of Discord argument followed. He sees the PHB text, but believes the "melee" designation in the summary field on dndbeyond was an intentional decision. He asserts that no other spell in the game is both melee and ranged, so True Strike couldn't stand alone as such. He points to Green Flame Blade and Booming Blade as examples of what he believes True Strike is meant to be modeled after. He says absent evidence of a coding error, it's an intentional change to the spell. He does not treat the tool set search engine fields or tags as superfluous (the way I see them), but as rules content themselves. He says the books and dndbeyond are "the same" and "both are the rules." We're pulling our hair out.

Quote from fractal_wolf >>

Same thing with Shillelagh. It says "Melee" but the spell itself is not a Melee attack...or ANY attack at all.

While I understand the intent, some people assume this restricts the spells mode or way its executed. I think WotC should improve/clarify these 'extra' fields.

 Just want to point out that Shillelagh does indeed say that you only can use your spell modifier for melee attacks:

"For the duration, you can use your spellcasting ability instead of Strength for the attack and damage rolls of melee attacks using that weapon, and the weapon’s damage die becomes a d8."

Yes - the issue fractal is pointing out is that it's not a spell attack (or any attack) itself. Yes, the weapon must be used in melee attacks. No debate there. But Shillelagh acts less like Booming Blade (which does involve an attack when you cast it) and more like Magic Weapon (which is a weapon buff and does not have the attack/save "melee" designation). Shillelagh buffs the weapon (for use in melee), but the spell itself is not a melee spell attack. So the designation seems misplaced. 

The metadata field is a version problem.
The 5.5e spell True Strike does involve a weapon attack, while the 5e spell does not.
Technically, this is not specifically a melee attack, just a weapon attack, according to the spell itself.

The 5e version says that "On your next turn, you gain advantage on your first attack roll against the target, provided that this spell hasn't ended." It has the metadata field for attack/save set to "none".

The 5.5e version instead has the metadata field set to "melee", since it involves an actual attack: "Guided by a flash of magical insight, you make one attack with the weapon used in the spell’s casting."
I would assume that the specific "melee" designation is because DDB does not have a designation for general weapon attacks at this point and the classes that get it usually use melee weapons (especially since artificer for example did not exist in 5.5e when the spell was released in the basic rules).

You might want to check with your DM that you're using the same version to play with.
If you're playing in 5e, you might want to make sure you are actually using the corresponding spell cards, maybe you need to make sure to check the "legacy" (from before the 5e revisions that are not part of 5.5e) versions of spells, since a lot of the metadata in the non-"legacy" spell cards has intransparently been updated to the 5.5e spells.
Hope that helps you a little more.